[armedbear-cvs] r14395 - in trunk/abcl: doc/asdf src/org/armedbear/lisp

mevenson at common-lisp.net mevenson at common-lisp.net
Sat Feb 16 16:21:17 UTC 2013


Author: mevenson
Date: Sat Feb 16 08:21:15 2013
New Revision: 14395

Log:
asdf: upgrade to asdf-2.29.

Modified:
   trunk/abcl/doc/asdf/asdf.texinfo
   trunk/abcl/src/org/armedbear/lisp/asdf.lisp

Modified: trunk/abcl/doc/asdf/asdf.texinfo
==============================================================================
--- trunk/abcl/doc/asdf/asdf.texinfo	Sat Feb 16 04:10:59 2013	(r14394)
+++ trunk/abcl/doc/asdf/asdf.texinfo	Sat Feb 16 08:21:15 2013	(r14395)
@@ -41,11 +41,11 @@
 You can find the latest version of this manual at
 @url{http://common-lisp.net/project/asdf/asdf.html}.
 
-ASDF Copyright @copyright{} 2001-2012 Daniel Barlow and contributors.
+ASDF Copyright @copyright{} 2001-2013 Daniel Barlow and contributors.
 
-This manual Copyright @copyright{} 2001-2012 Daniel Barlow and contributors.
+This manual Copyright @copyright{} 2001-2013 Daniel Barlow and contributors.
 
-This manual revised @copyright{} 2009-2012 Robert P. Goldman and Francois-Rene Rideau.
+This manual revised @copyright{} 2009-2013 Robert P. Goldman and Francois-Rene Rideau.
 
 Permission is hereby granted, free of charge, to any person obtaining
 a copy of this software and associated documentation files (the
@@ -157,6 +157,7 @@
 @cindex ASDF versions
 @cindex :asdf
 @cindex :asdf2
+ at cindex :asdf3
 
 ASDF is Another System Definition Facility:
 a tool for specifying how systems of Common Lisp software
@@ -176,16 +177,17 @@
 the ASDF internals and how to extend ASDF.
 
 @emph{Nota Bene}:
-We have released ASDF 2.000 on May 31st 2010.
-Subsequent releases of ASDF 2 have since then been included
+We have released ASDF 2.000 on May 31st 2010,
+and ASDF 3.0 on January 31st 2013.
+Releases of ASDF 2 and later have since then been included
 in all actively maintained CL implementations that used to bundle ASDF 1,
 plus some implementations that didn't use to,
 and has been made to work with all actively used CL implementations and a few more.
 @xref{FAQ,,``What has changed between ASDF 1 and ASDF 2?''}.
-Furthermore, it is possible to upgrade from ASDF 1 to ASDF 2 on the fly.
-For this reason, we have stopped supporting ASDF 1;
-if you are using ASDF 1 and are experiencing any kind of issues or limitations,
-we recommend you upgrade to ASDF 2
+Furthermore, it is possible to upgrade from ASDF 1 to ASDF 2 or ASDF 3 on the fly.
+For this reason, we have stopped supporting ASDF 1 and ASDF 2.
+If you are using ASDF 1 or ASDF 2 and are experiencing any kind of issues or limitations,
+we recommend you upgrade to ASDF 3
 --- and we explain how to do that. @xref{Loading ASDF}.
 
 Also note that ASDF is not to be confused with ASDF-Install.
@@ -217,7 +219,7 @@
 
 @section Loading a pre-installed ASDF
 
-Most recent Lisp implementations include a copy of ASDF 2.
+Most recent Lisp implementations include a copy of ASDF 2, and soon ASDF 3.
 You can usually load this copy using Common Lisp's @code{require} function:
 
 @lisp
@@ -233,7 +235,7 @@
 and most probably will never bundle it:
 cormanlisp gcl genera mcl.
 
-If the implementation you are using doesn't provide ASDF 2,
+If the implementation you are using doesn't provide ASDF 2 or ASDF 3,
 see @pxref{Loading ASDF,,Loading an otherwise installed ASDF} below.
 If that implementation is still actively maintained,
 you may also send a bug report to your Lisp vendor and complain
@@ -290,14 +292,14 @@
 
 @section Upgrading ASDF
 
-If your implementation provides ASDF 2.27 or later,
+If your implementation provides ASDF 3 or later,
 you only need to @code{(require "asdf")}:
 ASDF will automatically look whether an updated version of itself is available
 amongst the regularly configured systems, before it compiles anything else.
 See @pxref{Configuring ASDF} below.
 
 If your implementation does provide ASDF 2 or later,
-but not ASDF 2.27 or later,
+but not ASDF 3 or later,
 and you want to upgrade to a more recent version,
 you need to install and configure your ASDF as above,
 and additionally, you need to explicitly tell ASDF to load itself,
@@ -346,13 +348,13 @@
 when it is loaded on top of a different ASDF version,
 starting with ASDF 2.014.8 (as far as releases go, 2.015);
 and it will automatically attempt this self-upgrade as its very first step
-starting with ASDF 2.27.
+starting with ASDF 3.
 
 @item
 For this an many other reasons,
 it important reason to load, configure and upgrade ASDF (if needed)
 as one of the very first things done by your build and startup scripts.
-Until all implementations provide ASDF 2.27 or later,
+Until all implementations provide ASDF 3 or later,
 it is safer if you upgrade ASDF and its extensions as a special step
 at the very beginning of whatever script you are running,
 before you start using ASDF to load anything else;
@@ -360,7 +362,7 @@
 load and reload code twice as it gets invalidated.
 
 @item
-Until all implementations provide ASDF 2.27 or later,
+Until all implementations provide ASDF 3 or later,
 it is unsafe to upgrade ASDF as part of loading a system
 that depends on a more recent version of ASDF,
 since the new one might shadow the old one while the old one is running,
@@ -376,7 +378,7 @@
   (error "FOO requires ASDF ~A or later." *required-asdf-version*))
 @end example
 @item
-Until all implementations provide ASDF 2.27 or later,
+Until all implementations provide ASDF 3 or later,
 it is unsafe for a system to transitively depend on ASDF
 and not directly depend on ASDF;
 if any of the system you use either depends-on asdf,
@@ -490,7 +492,7 @@
 your Common Lisp software system.
 (For instance, some SBCL users used to put it in their @file{~/.sbclrc}.)
 
-The @code{asdf:*central-registry*} is empty by default in ASDF 2,
+The @code{asdf:*central-registry*} is empty by default in ASDF 2 or ASDF 3,
 but is still supported for compatibility with ASDF 1.
 When used, it takes precedence over the above source-registry at footnote{
 It is possible to further customize
@@ -695,7 +697,7 @@
 In older versions of ASDF, you needed to use
 @code{(asdf:oos 'asdf:load-op :@var{foo})}.
 If your ASDF is too old to provide @code{asdf:load-system} though
-we recommend that you upgrade to ASDF 2.
+we recommend that you upgrade to ASDF 3.
 @xref{Loading ASDF,,Loading an otherwise installed ASDF}.
 
 Note the name of a system is specified as a string or a symbol,
@@ -1319,10 +1321,10 @@
 As compared to using @code{#+} which is expanded at read-time,
 this allows you to have an object in your component hierarchy
 that can be used for manipulations beside building your project.
-This option was added in ASDF 2.27.
+This option was added in ASDF 3.
 
 @subsection if-component-dep-fails option
-This option was removed in ASDF 2.27.
+This option was removed in ASDF 3.
 Its semantics was limited in purpose and dubious to explain,
 and its implementation was breaking a hole into the ASDF object model.
 Please use the @code{if-feature} option instead.
@@ -1411,52 +1413,30 @@
 If, as a user, extender or implementer of ASDF, you fail
 to keep the dependency graph without cycles,
 ASDF will fail loudly as it eventually finds one.
-
 To clearly distinguish the direction of dependencies,
-ASDF 2.27 introduces the words @emph{parent} and @emph{child}
+ASDF 3 uses the words @emph{requiring} and @emph{required}
 as applied to an action depending on the other:
-the parent action @code{depends-on} the completion of all children actions
+the requiring action @code{depends-on} the completion of all required actions
 before it may itself be @code{perform}ed.
-ASDF has long had parent operations and children operations,
-whereby the ancestor holds some options valid for all the children (notably regarding forcing).
 
-Using the defsystem syntax, users may easily express
+Using the @code{defsystem} syntax, users may easily express
 direct dependencies along the graph of the object hierarchy:
 between a component and its parent, its children, and its siblings.
 By defining custom CLOS methods, you can express more elaborate dependencies as you wish.
 Most common operations, such as @code{load-op}, @code{compile-op} or @code{load-source-op}
-automatically ``descend'' the component hierarchy and are ``covariant'' with it:
+are automatically propagate ``downward'' the component hierarchy and are ``covariant'' with it:
 to act the operation on the parent module, you must first act it on all the children components,
 with the action on the parent being parent of the action on each child.
-Other operations, such as @code{parent-load-op} and @code{parent-load-source-op}
-(introduced in ASDF 2.27) ``ascend'' the component hierarchy and are ``contravariant'' with it:
-to act the operation on the child component, you must first act it on all its parent module, and so on,
-ensuring that all the module's dependencies are (compiled and) loaded
+Other operations, such as @code{prepare-op} and @code{prepare-source-op}
+(introduced in ASDF 3) are automatically propagated ``upward'' the component hierarchy
+and are ``contravariant'' with it:
+to perform the operation of preparing for compilation of a child component,
+you must perform the operation of preparing for compilation of its parent component, and so on,
+ensuring that all the parent's dependencies are (compiled and) loaded
 before the child component may be compiled and loaded.
 Yet other operations, such as @code{test-op} or @code{load-fasl-op}
-remain at the system level, and do not descend the hierarchy,
-instead doing something global.
-Finally, some operations such a POIU's @code{parallel-load-op}
-are not even meant to be performed or to have dependencies,
-but are only ways to specialize @code{operate} into behaving differently
-(in this case, having it operate in parallel).
-
-Parent and child thus mean different things for components and for actions.
-They also mean two different things for operations.
-Each operation has a @code{parent} slot,
-which links it up all the way to an ancestor @emph{operation}
-that contains all configuration data related to the current run of @code{operate}
-(usually the links are made with @code{make-sub-operation}
-which ensures the chain or parents is of length zero or one).
-Each operation also has a notion of a @code{parent-operation},
-such that current operation acting on a current component
-is parent of the parent-operation acting on the parent.
-That's how @code{parent-load-op} is the @code{parent-operation}
-or both @code{load-op} and @code{compile-op} (see above).
-
-It isn't too confusing: parent and child are generic ways to denote a clear directional relationship,
-and whether we're discussing component structure, action structure, operation structure
-or contravariant operation prerequisites, it is usually very clear which relationship we're discussing.
+remain at the system level, and are not propagated along the hierarchy,
+but instead do something global on the system.
 
 @menu
 * Operations::
@@ -1651,7 +1631,7 @@
 you should not forget to @code{(asdf:clear-configuration)}.
 
 @code{load-fasl-op} is available on all actively supported Lisp implementations,
-and on those implementations only, and only since ASDF 2.27.
+and on those implementations only, and only since ASDF 3.
 This functionality was previously available for select implementations,
 as part of a separate system @code{asdf-bundle},
 itself descended from @code{asdf-ecl}.
@@ -1899,7 +1879,7 @@
 @c @xref{Predefined operations of ASDF}.
 @c @emph{Nota Bene}:
 @c This operation, planned for ASDF 1,
- at c is still not implemented yet as of ASDF 2.
+ at c is still not implemented yet as of ASDF 3.
 @c Don't hold your breath.
 
 
@@ -2095,7 +2075,7 @@
 
 @item
 @code{:if-component-dep-fails}
-This attribute was removed in ASDF 2.27. Do not use it.
+This attribute was removed in ASDF 3. Do not use it.
 Use @code{:if-feature} instead.
 
 @item
@@ -2279,7 +2259,7 @@
 @code{CL:TRUENAME} to locate where your source code was and where to build it,
 allowing for symlink farms as a simple but effective configuration mechanism
 that is easy to control programmatically.
-ASDF2 still supports this configuration style, and it is enabled by default;
+ASDF 3 still supports this configuration style, and it is enabled by default;
 however we recommend you instead use
 our source-registry configuration mechanism described below,
 because it is easier to setup in a portable way across users and implementations.
@@ -2289,7 +2269,7 @@
 because they are using content-addressed storage where the truename of a file
 is related to a digest of its individual contents,
 and not to other files in the same intended project.
-For these people, ASDF 2.27 allows to eschew the @code{TRUENAME} mechanism,
+For these people, ASDF 3 allows to eschew the @code{TRUENAME} mechanism,
 by setting the variable @var{asdf:*resolve-symlinks*} to @code{NIL}.
 
 PS: Yes, if you haven't read Vernor Vinge's short but great classic
@@ -2315,7 +2295,7 @@
 @code{Common AppData} and similar directories.
 Since support for querying the Windows registry
 is not possible to do in reasonable amounts of portable Common Lisp code,
-ASDF 2 relies on the environment variables that Windows usually exports.
+ASDF 3 relies on the environment variables that Windows usually exports.
 
 @section Backward Compatibility
 
@@ -2729,7 +2709,7 @@
 which means that you'll have to recompile binaries
 as you switch from one implementation to the next.
 
-ASDF 2 includes the @code{asdf-output-translations} facility
+Since ASDF 2, ASDF includes the @code{asdf-output-translations} facility
 to mitigate the problem.
 
 @section Configurations
@@ -3592,7 +3572,7 @@
 in a way that preserves semantics.
 
 Instead we recommend the use @code{run-program} above
-available as part of ASDF since ASDF 2.27.
+available as part of ASDF since ASDF 3.
 
 @code{run-shell-command} takes as arguments a @code{format} control-string
 and arguments to be passed to @code{format} after this control-string
@@ -3776,7 +3756,7 @@
 In particular, dependencies were not correctly propagated
 across modules but now are.
 It has been completely rewritten many times over
-between ASDF 2.000 and ASDF 2.27,
+between ASDF 2.000 and ASDF 3,
 with fundamental issues in the original model being fixed.
 Timestamps were not propagated at all, and now are.
 The internal model of how actions depend on each other
@@ -3981,8 +3961,8 @@
 
 @subsection ``I'm a Common Lisp implementation vendor. When and how should I upgrade ASDF?''
 
-Starting with current candidate releases of ASDF 2,
-it should always be a good time to upgrade to a recent ASDF.
+Since ASDF 2,
+it should always be a good time to upgrade to a recent version of ASDF.
 You may consult with the maintainer for which specific version they recommend,
 but the latest @code{release} should be correct.
 We trust you to thoroughly test it with your implementation
@@ -4292,7 +4272,7 @@
 It is possible to achieve the same effect
 in a way that supports both ASDF 1 and ASDF 2,
 but really, friends don't let friends use ASDF 1.
-Please upgrade to ASDF 2.
+Please upgrade to ASDF 3.
 In short, though: do same as above, but
 @emph{before} you use the class in a @code{defsystem},
 you also define the following method:

Modified: trunk/abcl/src/org/armedbear/lisp/asdf.lisp
==============================================================================
--- trunk/abcl/src/org/armedbear/lisp/asdf.lisp	Sat Feb 16 04:10:59 2013	(r14394)
+++ trunk/abcl/src/org/armedbear/lisp/asdf.lisp	Sat Feb 16 08:21:15 2013	(r14395)
@@ -1,5 +1,5 @@
 ;;; -*- mode: Common-Lisp; Base: 10 ; Syntax: ANSI-Common-Lisp -*-
-;;; This is ASDF 2.26.158.1: Another System Definition Facility.
+;;; This is ASDF 2.29: Another System Definition Facility.
 ;;;
 ;;; Feedback, bug reports, and patches are all welcome:
 ;;; please mail to <asdf-devel at common-lisp.net>.
@@ -49,16 +49,12 @@
 
 (in-package :cl-user)
 
-;; #+abcl
-;; (eval-when (:load-toplevel :compile-toplevel :execute)
-;;   (documentation 'car 'function)) ;; workaround (SETF DOCUMENTATION) autoloader bug
-
 #+cmu
 (eval-when (:load-toplevel :compile-toplevel :execute)
   (declaim (optimize (speed 1) (safety 3) (debug 3)))
   (setf ext:*gc-verbose* nil))
 
-#+(or abcl clisp cmu)
+#+(or abcl clisp cmu ecl xcl)
 (eval-when (:load-toplevel :compile-toplevel :execute)
   (unless (member :asdf3 *features*)
     (let* ((existing-version
@@ -69,11 +65,16 @@
                        (string ver)
                        (cons (format nil "~{~D~^.~}" ver))
                        (null "1.0"))))))
+           (first-dot (when existing-version (position #\. existing-version)))
+           (second-dot (when first-dot (position #\. existing-version :start (1+ first-dot))))
+           (existing-major-minor (subseq existing-version 0 second-dot))
+           (existing-version-number (and existing-version (read-from-string existing-major-minor)))
            (away (format nil "~A-~A" :asdf existing-version)))
-      (when existing-version
+      (when (and existing-version (< existing-version-number
+                                     #+abcl 2.25 #+clisp 2.27 #+cmu 2.018 #+ecl 2.21 #+xcl 2.27))
         (rename-package :asdf away)
         (when *load-verbose*
-          (format t "; Renamed package ~A away to ~A~%" :asdf away))))))
+          (format t "; Renamed old ~A package away to ~A~%" :asdf away))))))
 
 ;;;; ---------------------------------------------------------------------------
 ;;;; Handle ASDF package upgrade, including implementation-dependent magic.
@@ -197,16 +198,9 @@
 (eval-when (:load-toplevel :compile-toplevel :execute)
   (defvar *all-package-happiness* '())
   (defvar *all-package-fishiness* (list t))
-  (defvar *package-fishiness* '())
-  (defun flush-fishy ()
-    (when *package-fishiness*
-      (if (null (rest *package-fishiness*))
-          (push (first *package-fishiness*) *all-package-happiness*)
-          (push (nreverse *package-fishiness*) *all-package-fishiness*))
-      (setf *package-fishiness* nil)))
   (defun record-fishy (info)
     ;;(format t "~&FISHY: ~S~%" info)
-    (push info *package-fishiness*))
+    (push info *all-package-fishiness*))
   (defmacro when-package-fishiness (&body body)
     `(when *all-package-fishiness* , at body))
   (defmacro note-package-fishiness (&rest info)
@@ -284,9 +278,9 @@
                   (and overwritten-symbol-status
                        (symbol-shadowing-p overwritten-symbol package))))
             (note-package-fishiness
-             :rehome-symbol name (package-name old-package)
-             (package-name package) old-status (and shadowing t)
-             overwritten-symbol-status overwritten-symbol-shadowing-p)
+             :rehome-symbol name
+             (when old-package (package-name old-package)) old-status (and shadowing t)
+             (package-name package) overwritten-symbol-status overwritten-symbol-shadowing-p)
             (when old-package
               (if shadowing
                   (shadowing-import shadowing old-package))
@@ -414,8 +408,215 @@
 
 
 ;;; ensure-package, define-package
-
 (eval-when (:load-toplevel :compile-toplevel :execute)
+  (defun ensure-shadowing-import (name to-package from-package shadowed imported)
+    (check-type name string)
+    (check-type to-package package)
+    (check-type from-package package)
+    (check-type shadowed hash-table)
+    (check-type imported hash-table)
+    (let ((import-me (find-symbol* name from-package)))
+      (multiple-value-bind (existing status) (find-symbol name to-package)
+        (cond
+          ((gethash name shadowed)
+           (unless (eq import-me existing)
+             (error "Conflicting shadowings for ~A" name)))
+          (t
+           (setf (gethash name shadowed) t)
+           (setf (gethash name imported) t)
+           (unless (or (null status)
+                       (and (member status '(:internal :external))
+                            (eq existing import-me)
+                            (symbol-shadowing-p existing to-package)))
+             (note-package-fishiness
+              :shadowing-import name
+              (package-name from-package)
+              (or (home-package-p import-me from-package) (symbol-package-name import-me))
+              (package-name to-package) status
+              (and status (or (home-package-p existing to-package) (symbol-package-name existing)))))
+           (shadowing-import import-me to-package))))))
+  (defun ensure-import (name to-package from-package shadowed imported)
+    (check-type name string)
+    (check-type to-package package)
+    (check-type from-package package)
+    (check-type shadowed hash-table)
+    (check-type imported hash-table)
+    (multiple-value-bind (import-me import-status) (find-symbol name from-package)
+      (when (null import-status)
+        (note-package-fishiness
+         :import-uninterned name (package-name from-package) (package-name to-package))
+        (setf import-me (intern name from-package)))
+      (multiple-value-bind (existing status) (find-symbol name to-package)
+        (cond
+          ((gethash name imported)
+           (unless (eq import-me existing)
+             (error "Can't import ~S from both ~S and ~S"
+                    name (package-name (symbol-package existing)) (package-name from-package))))
+          ((gethash name shadowed)
+           (error "Can't both shadow ~S and import it from ~S" name (package-name from-package)))
+          (t
+           (setf (gethash name imported) t)
+           (unless (and status (eq import-me existing))
+             (when status
+               (note-package-fishiness
+                :import name
+                (package-name from-package)
+                (or (home-package-p import-me from-package) (symbol-package-name import-me))
+                (package-name to-package) status
+                (and status (or (home-package-p existing to-package) (symbol-package-name existing))))
+               (unintern* existing to-package))
+             (import import-me to-package)))))))
+  (defun ensure-inherited (name symbol to-package from-package mixp shadowed imported inherited)
+    (check-type name string)
+    (check-type symbol symbol)
+    (check-type to-package package)
+    (check-type from-package package)
+    (check-type mixp (member nil t)) ; no cl:boolean on Genera
+    (check-type shadowed hash-table)
+    (check-type imported hash-table)
+    (check-type inherited hash-table)
+    (multiple-value-bind (existing status) (find-symbol name to-package)
+      (let* ((sp (symbol-package symbol))
+             (in (gethash name inherited))
+             (xp (and status (symbol-package existing))))
+        (when (null sp)
+          (note-package-fishiness
+           :import-uninterned name
+           (package-name from-package) (package-name to-package) mixp)
+          (import symbol from-package)
+          (setf sp (package-name from-package)))
+        (cond
+          ((gethash name shadowed))
+          (in
+           (unless (equal sp (first in))
+             (if mixp
+                 (ensure-shadowing-import name to-package (second in) shadowed imported)
+                 (error "Can't inherit ~S from ~S, it is inherited from ~S"
+                        name (package-name sp) (package-name (first in))))))
+          ((gethash name imported)
+           (unless (eq symbol existing)
+             (error "Can't inherit ~S from ~S, it is imported from ~S"
+                    name (package-name sp) (package-name xp))))
+          (t
+           (setf (gethash name inherited) (list sp from-package))
+           (when (and status (not (eq sp xp)))
+             (let ((shadowing (symbol-shadowing-p existing to-package)))
+               (note-package-fishiness
+                :inherited name
+                (package-name from-package)
+                (or (home-package-p symbol from-package) (symbol-package-name symbol))
+                (package-name to-package)
+                (or (home-package-p existing to-package) (symbol-package-name existing)))
+               (if shadowing (ensure-shadowing-import name to-package from-package shadowed imported)
+                   (unintern* existing to-package)))))))))
+  (defun ensure-mix (name symbol to-package from-package shadowed imported inherited)
+    (check-type name string)
+    (check-type symbol symbol)
+    (check-type to-package package)
+    (check-type from-package package)
+    (check-type shadowed hash-table)
+    (check-type imported hash-table)
+    (check-type inherited hash-table)
+    (unless (gethash name shadowed)
+      (multiple-value-bind (existing status) (find-symbol name to-package)
+        (let* ((sp (symbol-package symbol))
+               (im (gethash name imported))
+               (in (gethash name inherited)))
+          (cond
+            ((or (null status)
+                 (and status (eq symbol existing))
+                 (and in (eq sp (first in))))
+             (ensure-inherited name symbol to-package from-package t shadowed imported inherited))
+            (in
+             (remhash name inherited)
+             (ensure-shadowing-import name to-package (second in) shadowed imported))
+            (im
+             (error "Symbol ~S import from ~S~:[~; actually ~:[uninterned~;~:*from ~S~]~] conflicts with existing symbol in ~S~:[~; actually ~:[uninterned~;from ~:*~S~]~]"
+                    name (package-name from-package)
+                    (home-package-p symbol from-package) (symbol-package-name symbol)
+                    (package-name to-package)
+                    (home-package-p existing to-package) (symbol-package-name existing)))
+            (t
+             (ensure-inherited name symbol to-package from-package t shadowed imported inherited)))))))
+  (defun recycle-symbol (name recycle exported)
+    (check-type name string)
+    (check-type recycle list)
+    (check-type exported hash-table)
+    (when (gethash name exported) ;; don't bother recycling private symbols
+      (let (recycled foundp)
+        (dolist (r recycle (values recycled foundp))
+          (multiple-value-bind (symbol status) (find-symbol name r)
+            (when (and status (home-package-p symbol r))
+              (cond
+                (foundp
+                 ;; (nuke-symbol symbol)) -- even simple variable names like O or C will do that.
+                 (note-package-fishiness :recycled-duplicate name (package-name foundp) (package-name r)))
+                (t
+                 (setf recycled symbol foundp r)))))))))
+  (defun symbol-recycled-p (sym recycle)
+    (check-type sym symbol)
+    (check-type recycle list)
+    (member (symbol-package sym) recycle))
+  (defun ensure-symbol (name package intern recycle shadowed imported inherited exported)
+    (check-type name string)
+    (check-type package package)
+    (check-type intern (member nil t)) ; no cl:boolean on Genera
+    (check-type shadowed hash-table)
+    (check-type imported hash-table)
+    (check-type inherited hash-table)
+    (unless (or (gethash name shadowed)
+                (gethash name imported)
+                (gethash name inherited))
+      (multiple-value-bind (existing status)
+          (find-symbol name package)
+        (multiple-value-bind (recycled previous) (recycle-symbol name recycle exported)
+          (cond
+            ((and status (eq existing recycled) (eq previous package)))
+            (previous
+             (rehome-symbol recycled package))
+            ((and status (eq package (symbol-package existing))))
+            (t
+             (when status
+               (note-package-fishiness
+                :ensure-symbol name
+                (reify-package (symbol-package existing) package)
+                status intern)
+               (unintern existing))
+             (when intern
+               (intern* name package))))))))
+  (declaim (ftype function ensure-exported))
+  (defun ensure-exported-to-user (name symbol to-package &optional recycle)
+    (check-type name string)
+    (check-type symbol symbol)
+    (check-type to-package package)
+    (check-type recycle list)
+    (multiple-value-bind (existing status) (find-symbol name to-package)
+      (unless (and status (eq symbol existing))
+        (let ((accessible
+                (or (null status)
+                    (let ((shadowing (symbol-shadowing-p existing to-package))
+                          (recycled (symbol-recycled-p existing recycle)))
+                      (unless (and shadowing (not recycled))
+                        (note-package-fishiness
+                         :ensure-export name (symbol-package-name symbol)
+                         (package-name to-package)
+                         (or (home-package-p existing to-package) (symbol-package-name existing))
+                         status shadowing)
+                        (if (or (eq status :inherited) shadowing)
+                            (shadowing-import symbol to-package)
+                            (unintern existing to-package))
+                        t)))))
+          (when (and accessible (eq status :external))
+            (ensure-exported name symbol to-package recycle))))))
+  (defun ensure-exported (name symbol from-package &optional recycle)
+    (dolist (to-package (package-used-by-list from-package))
+      (ensure-exported-to-user name symbol to-package recycle))
+    (import symbol from-package)
+    (export* name from-package))
+  (defun ensure-export (name from-package &optional recycle)
+    (multiple-value-bind (symbol status) (find-symbol* name from-package)
+      (unless (eq status :external)
+        (ensure-exported name symbol from-package recycle))))
   (defun ensure-package (name &key
                                 nicknames documentation use
                                 shadow shadowing-import-from
@@ -423,239 +624,99 @@
                                 recycle mix reexport
                                 unintern)
     #+(or gcl2.6 genera) (declare (ignore documentation))
-    (macrolet ((when-fishy (&body body) `(when-package-fishiness , at body))
-               (fishy (&rest info) `(note-package-fishiness , at info)))
-      (let* ((package-name (string name))
-             (nicknames (mapcar #'string nicknames))
-             (names (cons package-name nicknames))
-             (previous (packages-from-names names))
-             (discarded (cdr previous))
-             (to-delete ())
-             (package (or (first previous) (make-package package-name :nicknames nicknames)))
-             (recycle (packages-from-names recycle))
-             (use (mapcar 'find-package* use))
-             (mix (mapcar 'find-package* mix))
-             (reexport (mapcar 'find-package* reexport))
-             (shadow (mapcar 'string shadow))
-             (export (mapcar 'string export))
-             (intern (mapcar 'string intern))
-             (unintern (mapcar 'string unintern))
-             (shadowed (make-hash-table :test 'equal)) ; string to bool
-             (imported (make-hash-table :test 'equal)) ; string to bool
-             (exported (make-hash-table :test 'equal)) ; string to bool
-             ;; string to list home package and use package:
-             (inherited (make-hash-table :test 'equal)))
-        (when-fishy (record-fishy package-name))
-        (labels
-            ((ensure-shadowing-import (name p)
-               (let ((import-me (find-symbol* name p)))
-                 (multiple-value-bind (existing status) (find-symbol name package)
-                   (cond
-                     ((gethash name shadowed)
-                      (unless (eq import-me existing)
-                        (error "Conflicting shadowings for ~A" name)))
-                     (t
-                      (setf (gethash name shadowed) t)
-                      (setf (gethash name imported) t)
-                      (unless (or (null status)
-                                  (and (member status '(:internal :external))
-                                       (eq existing import-me)
-                                       (symbol-shadowing-p existing package)))
-                        (fishy :shadowing-import
-                               name (package-name p) (symbol-package-name import-me)
-                               (and status (symbol-package-name existing)) status))
-                      (shadowing-import import-me package))))))
-             (ensure-import (sym p)
-               (let* ((name (string sym))
-                      (import-me (find-symbol* name p)))
-                 (multiple-value-bind (existing status) (find-symbol name package)
-                   (cond
-                     ((gethash name imported)
-                      (unless (eq import-me existing)
-                        (error "Can't import ~S from both ~S and ~S"
-                               name (package-name (symbol-package existing)) (package-name p))))
-                     ((gethash name shadowed)
-                      (error "Can't both shadow ~S and import it from ~S" name (package-name p)))
-                     (t
-                      (setf (gethash name imported) t)
-                      (unless (and status (eq import-me existing))
-                        (when status
-                          (fishy :import name (package-name p) (symbol-package-name import-me)
-                                 (and status (symbol-package-name existing)) status)
-                          (unintern* existing package))
-                        (import import-me package)))))))
-             (ensure-mix (name symbol p)
-               (unless (gethash name shadowed)
-                 (multiple-value-bind (existing status) (find-symbol name package)
-                   (let* ((sp (symbol-package symbol))
-                          (im (gethash name imported))
-                          (in (gethash name inherited)))
-                     (cond
-                       ((or (null status)
-                            (and status (eq symbol existing))
-                            (and in (eq sp (first in))))
-                        (ensure-inherited name symbol p t))
-                       (in
-                        (remhash name inherited)
-                        (ensure-shadowing-import name (second in)))
-                       (im
-                         (error "Imported symbol ~S conflicts with inherited symbol ~S in ~S"
-                                existing symbol (package-name package)))
-                       (t
-                        (ensure-inherited name symbol p t)))))))
-             (ensure-inherited (name symbol p mix)
-               (multiple-value-bind (existing status) (find-symbol name package)
-                 (let* ((sp (symbol-package symbol))
-                        (in (gethash name inherited))
-                        (xp (and status (symbol-package existing))))
-                   (when (null sp)
-                     (fishy :import-uninterned name (package-name p) mix)
-                     (import symbol p)
-                     (setf sp (package-name p)))
-                   (cond
-                     ((gethash name shadowed))
-                     (in
-                      (unless (equal sp (first in))
-                        (if mix
-                            (ensure-shadowing-import name (second in))
-                            (error "Can't inherit ~S from ~S, it is inherited from ~S"
-                                   name (package-name sp) (package-name (first in))))))
-                     ((gethash name imported)
-                      (unless (eq symbol existing)
-                        (error "Can't inherit ~S from ~S, it is imported from ~S"
-                               name (package-name sp) (package-name xp))))
-                     (t
-                      (setf (gethash name inherited) (list sp p))
-                      (when (and status (not (eq sp xp)))
-                        (let ((shadowing (symbol-shadowing-p existing package)))
-                          (fishy :inherited name (package-name p) (package-name sp)
-                                 (package-name xp))
-                          (if shadowing (ensure-shadowing-import name p)
-                              (unintern* existing package)))))))))
-             (recycle-symbol (name)
-               (when (gethash name exported) ;; don't bother recycling private symbols
-                 (let (recycled foundp)
-                   (dolist (r recycle (values recycled foundp))
-                     (multiple-value-bind (symbol status) (find-symbol name r)
-                       (when (and status (home-package-p symbol r))
-                         (cond
-                           (foundp
-                            ;; (nuke-symbol symbol)) -- even simple variable names like O or C will do that.
-                            (fishy :recycled-duplicate name (package-name foundp) (package-name r)))
-                           (t
-                            (setf recycled symbol foundp r)))))))))
-             (symbol-recycled-p (sym)
-               (member (symbol-package sym) recycle))
-             (ensure-symbol (name &optional intern)
-               (unless (or (gethash name shadowed)
-                           (gethash name imported)
-                           (gethash name inherited))
-                 (multiple-value-bind (existing status)
-                     (find-symbol name package)
-                   (multiple-value-bind (recycled previous) (recycle-symbol name)
-                     (cond
-                       ((and status (eq existing recycled) (eq previous package)))
-                       (previous
-                        (rehome-symbol recycled package))
-                       ((and status (eq package (symbol-package existing))))
-                       (t
-                        (when status
-                          (fishy :ensure-symbol name
-                                 (reify-package (symbol-package existing) package)
-                                 status intern)
-                          (unintern existing))
-                        (when intern
-                          (intern* name package))))))))
-             (ensure-export (name p)
-               (multiple-value-bind (symbol status) (find-symbol* name p)
-                 (unless (eq status :external)
-                   (ensure-exported name symbol p))))
-             (ensure-exported (name sym p)
-               (dolist (u (package-used-by-list p))
-                 (ensure-exported-to-user name sym u))
-               (export* sym p))
-             (ensure-exported-to-user (name sym u)
-               (multiple-value-bind (usym ustat) (find-symbol name u)
-                 (unless (and ustat (eq sym usym))
-                   (let ((accessible
-                           (or (null ustat)
-                               (let ((shadowing (symbol-shadowing-p usym u))
-                                     (recycled (symbol-recycled-p usym)))
-                                 (unless (and shadowing (not recycled))
-                                   (fishy :ensure-export name (symbol-package-name sym)
-                                          (package-name u)
-                                          (and ustat (symbol-package-name usym)) ustat shadowing)
-                                   (if (or (eq ustat :inherited) shadowing)
-                                       (shadowing-import sym u)
-                                       (unintern usym u))
-                                   t)))))
-                     (when (and accessible (eq ustat :external))
-                       (ensure-exported name sym u)))))))
-          #-(or gcl2.6 genera)
-          (when documentation (setf (documentation package t) documentation))
-          (loop :for p :in (set-difference (package-use-list package) (append mix use))
-                :do (fishy :use (package-names p)) (unuse-package p package))
-          (loop :for p :in discarded
-                :for n = (remove-if #'(lambda (x) (member x names :test 'equal))
-                                    (package-names p))
-                :do (fishy :nickname (package-names p))
-                    (cond (n (rename-package p (first n) (rest n)))
-                          (t (rename-package-away p)
-                             (push p to-delete))))
-          (rename-package package package-name nicknames)
-          (dolist (name unintern)
-            (multiple-value-bind (existing status) (find-symbol name package)
-              (when status
-                (unless (eq status :inherited)
-                  (fishy :unintern name (symbol-package-name existing) status)
-                  (unintern* name package nil)))))
-          (dolist (name export)
-            (setf (gethash name exported) t))
-          (dolist (p reexport)
-            (do-external-symbols (sym p)
-              (setf (gethash (string sym) exported) t)))
-          (do-external-symbols (sym package)
-            (let ((name (symbol-name sym)))
-              (unless (gethash name exported)
-                (fishy :over-exported name (symbol-package-name sym))
-                (unexport sym package))))
-          (dolist (name shadow)
-            (setf (gethash name shadowed) t)
-            (multiple-value-bind (existing status) (find-symbol name package)
-              (multiple-value-bind (recycled previous) (recycle-symbol name)
-                (let ((shadowing (and status (symbol-shadowing-p existing package))))
-                  (cond
-                    ((eq previous package))
-                    (previous
-                     (rehome-symbol recycled package))
-                    ((or (member status '(nil :inherited))
-                         (home-package-p existing package)))
-                    (t
-                     (let ((dummy (make-symbol name)))
-                       (fishy :shadow-imported name (symbol-package-name existing) status shadowing)
-                       (shadowing-import dummy package)
-                       (import dummy package)))))))
-            (shadow name package))
-          (loop :for (p . syms) :in shadowing-import-from
-                :for pp = (find-package* p) :do
-                  (dolist (sym syms) (ensure-shadowing-import (string sym) pp)))
-          (dolist (p mix)
-            (do-external-symbols (sym p) (ensure-mix (symbol-name sym) sym p)))
-          (loop :for (p . syms) :in import-from :do
-            (dolist (sym syms) (ensure-import sym p)))
-          (dolist (p (append use mix))
-            (do-external-symbols (sym p) (ensure-inherited (string sym) sym p nil))
-            (use-package p package))
-          (loop :for name :being :the :hash-keys :of exported :do
-            (ensure-symbol name t)
-            (ensure-export name package))
-          (dolist (name intern)
-            (ensure-symbol name t))
-          (do-symbols (sym package)
-            (ensure-symbol (symbol-name sym)))
-          (map () 'delete-package* to-delete)
-          (flush-fishy)
-          package)))))
+    (let* ((package-name (string name))
+           (nicknames (mapcar #'string nicknames))
+           (names (cons package-name nicknames))
+           (previous (packages-from-names names))
+           (discarded (cdr previous))
+           (to-delete ())
+           (package (or (first previous) (make-package package-name :nicknames nicknames)))
+           (recycle (packages-from-names recycle))
+           (use (mapcar 'find-package* use))
+           (mix (mapcar 'find-package* mix))
+           (reexport (mapcar 'find-package* reexport))
+           (shadow (mapcar 'string shadow))
+           (export (mapcar 'string export))
+           (intern (mapcar 'string intern))
+           (unintern (mapcar 'string unintern))
+           (shadowed (make-hash-table :test 'equal)) ; string to bool
+           (imported (make-hash-table :test 'equal)) ; string to bool
+           (exported (make-hash-table :test 'equal)) ; string to bool
+           ;; string to list home package and use package:
+           (inherited (make-hash-table :test 'equal)))
+      (when-package-fishiness (record-fishy package-name))
+      #-(or gcl2.6 genera)
+      (when documentation (setf (documentation package t) documentation))
+      (loop :for p :in (set-difference (package-use-list package) (append mix use))
+            :do (note-package-fishiness :over-use name (package-names p))
+                (unuse-package p package))
+      (loop :for p :in discarded
+            :for n = (remove-if #'(lambda (x) (member x names :test 'equal))
+                                (package-names p))
+            :do (note-package-fishiness :nickname name (package-names p))
+                (cond (n (rename-package p (first n) (rest n)))
+                      (t (rename-package-away p)
+                         (push p to-delete))))
+      (rename-package package package-name nicknames)
+      (dolist (name unintern)
+        (multiple-value-bind (existing status) (find-symbol name package)
+          (when status
+            (unless (eq status :inherited)
+              (note-package-fishiness
+               :unintern (package-name package) name (symbol-package-name existing) status)
+              (unintern* name package nil)))))
+      (dolist (name export)
+        (setf (gethash name exported) t))
+      (dolist (p reexport)
+        (do-external-symbols (sym p)
+          (setf (gethash (string sym) exported) t)))
+      (do-external-symbols (sym package)
+        (let ((name (symbol-name sym)))
+          (unless (gethash name exported)
+            (note-package-fishiness
+             :over-export (package-name package) name
+             (or (home-package-p sym package) (symbol-package-name sym)))
+            (unexport sym package))))
+      (dolist (name shadow)
+        (setf (gethash name shadowed) t)
+        (multiple-value-bind (existing status) (find-symbol name package)
+          (multiple-value-bind (recycled previous) (recycle-symbol name recycle exported)
+            (let ((shadowing (and status (symbol-shadowing-p existing package))))
+              (cond
+                ((eq previous package))
+                (previous
+                 (rehome-symbol recycled package))
+                ((or (member status '(nil :inherited))
+                     (home-package-p existing package)))
+                (t
+                 (let ((dummy (make-symbol name)))
+                   (note-package-fishiness
+                    :shadow-imported (package-name package) name
+                    (symbol-package-name existing) status shadowing)
+                   (shadowing-import dummy package)
+                   (import dummy package)))))))
+        (shadow name package))
+      (loop :for (p . syms) :in shadowing-import-from
+            :for pp = (find-package* p) :do
+              (dolist (sym syms) (ensure-shadowing-import (string sym) package pp shadowed imported)))
+      (loop :for p :in mix
+            :for pp = (find-package* p) :do
+              (do-external-symbols (sym pp) (ensure-mix (symbol-name sym) sym package pp shadowed imported inherited)))
+      (loop :for (p . syms) :in import-from
+            :for pp = (find-package p) :do
+              (dolist (sym syms) (ensure-import (symbol-name sym) package pp shadowed imported)))
+      (dolist (p (append use mix))
+        (do-external-symbols (sym p) (ensure-inherited (string sym) sym package p nil shadowed imported inherited))
+        (use-package p package))
+      (loop :for name :being :the :hash-keys :of exported :do
+        (ensure-symbol name package t recycle shadowed imported inherited exported)
+        (ensure-export name package recycle))
+      (dolist (name intern)
+        (ensure-symbol name package t recycle shadowed imported inherited exported))
+      (do-symbols (sym package)
+        (ensure-symbol (symbol-name sym) package nil recycle shadowed imported inherited exported))
+      (map () 'delete-package* to-delete)
+      package)))
 
 (eval-when (:load-toplevel :compile-toplevel :execute)
   (defun parse-define-package-form (package clauses)
@@ -771,7 +832,7 @@
   (setf *print-readably* nil))
 
 #+cormanlisp
-(progn
+(eval-when (:load-toplevel :compile-toplevel :execute)
   (deftype logical-pathname () nil)
   (defun make-broadcast-stream () *error-output*)
   (defun translate-logical-pathname (x) x)
@@ -805,8 +866,8 @@
   (export 'type-of :asdf/common-lisp)
   (export 'system:*load-pathname* :asdf/common-lisp))
 
-#+gcl2.6
-(progn ;; Doesn't support either logical-pathnames or output-translations.
+#+gcl2.6 ;; Doesn't support either logical-pathnames or output-translations.
+(eval-when (:load-toplevel :compile-toplevel :execute)
   (defvar *gcl2.6* t)
   (deftype logical-pathname () nil)
   (defun type-of (x) (class-name (class-of x)))
@@ -832,13 +893,14 @@
                          (namestring (make-pathname :name nil :type nil :version nil :defaults path))))))
 
 #+genera
-(unless (fboundp 'ensure-directories-exist)
-  (defun ensure-directories-exist (path)
-    (fs:create-directories-recursively (pathname path))))
+(eval-when (:load-toplevel :compile-toplevel :execute)
+  (unless (fboundp 'ensure-directories-exist)
+    (defun ensure-directories-exist (path)
+      (fs:create-directories-recursively (pathname path)))))
 
-#.(or #+mcl ;; the #$ doesn't work on other lisps, even protected by #+mcl
+#.(or #+mcl ;; the #$ doesn't work on other lisps, even protected by #+mcl, so we use this trick
       (read-from-string
-       "(eval-when (:compile-toplevel :load-toplevel :execute)
+       "(eval-when (:load-toplevel :compile-toplevel :execute)
           (ccl:define-entry-point (_getenv \"getenv\") ((name :string)) :string)
           (ccl:define-entry-point (_system \"system\") ((name :string)) :int)
           ;; Note: ASDF may expect user-homedir-pathname to provide
@@ -862,9 +924,10 @@
 
 
 ;;;; Looping
-(defmacro loop* (&rest rest)
-  #-genera `(loop , at rest)
-  #+genera `(lisp:loop , at rest)) ;; In genera, CL:LOOP can't destructure, so we use LOOP*. Sigh.
+(eval-when (:load-toplevel :compile-toplevel :execute)
+  (defmacro loop* (&rest rest)
+    #-genera `(loop , at rest)
+    #+genera `(lisp:loop , at rest))) ;; In genera, CL:LOOP can't destructure, so we use LOOP*. Sigh.
 
 
 ;;;; compatfmt: avoid fancy format directives when unsupported
@@ -874,28 +937,29 @@
       (labels ((emit (start end)
                  (when (and (zerop start) (= end length))
                    (return-from remove-substrings string))
-                 (unless stream (setf stream (make-string-output-stream)))
-                 (write-string string stream :start start :end end))
+                 (when (< start end)
+                   (unless stream (setf stream (make-string-output-stream)))
+                   (write-string string stream :start start :end end)))
                (recurse (substrings start end)
                  (cond
-                   ((= start end))
+                   ((>= start end))
                    ((null substrings) (emit start end))
                    (t (let* ((sub (first substrings))
-                             (found (search sub string))
+                             (found (search sub string :start2 start :end2 end))
                              (more (rest substrings)))
                         (cond
                           (found
                            (recurse more start found)
-                           (recurse more (+ found (length sub)) end))
+                           (recurse substrings (+ found (length sub)) end))
                           (t
                            (recurse more start end))))))))
         (recurse substrings 0 length))
-      (if stream (get-output-stream-string stream) ""))))
+      (if stream (get-output-stream-string stream) "")))
 
-(defmacro compatfmt (format)
-  #+(or gcl genera)
-  (remove-substrings `("~3i~_" #+(or genera gcl2.6) ,@'("~@<" "~@;" "~@:>" "~:>")) format)
-  #-(or gcl genera) format)
+  (defmacro compatfmt (format)
+    #+(or gcl genera)
+    (remove-substrings `("~3i~_" #+(or genera gcl2.6) ,@'("~@<" "~@;" "~@:>" "~:>")) format)
+    #-(or gcl genera) format))
 
 
 ;;;; -------------------------------------------------------------------------
@@ -912,7 +976,7 @@
   (:export
    ;; magic helper to define debugging functions:
    #:asdf-debug #:load-asdf-debug-utility #:*asdf-debug-utility*
-   #:undefine-function #:undefine-functions #:defun* #:defgeneric* ;; (un)defining functions
+   #:undefine-function #:undefine-functions #:defun* #:defgeneric* #:with-upgradability ;; (un)defining functions
    #:if-let ;; basic flow control
    #:while-collecting #:appendf #:length=n-p #:remove-plist-keys #:remove-plist-key ;; lists and plists
    #:emptyp ;; sequences
@@ -928,7 +992,8 @@
    #:match-condition-p #:match-any-condition-p ;; conditions
    #:call-with-muffled-conditions #:with-muffled-conditions
    #:load-string #:load-stream
-   #:parse-version #:unparse-version #:version-compatible-p)) ;; version
+   #:lexicographic< #:lexicographic<=
+   #:parse-version #:unparse-version #:version< #:version<= #:version-compatible-p)) ;; version
 (in-package :asdf/utility)
 
 ;;;; Defining functions in a way compatible with hot-upgrade:
@@ -951,69 +1016,82 @@
        #-gcl2.6 (fmakunbound function-spec))
       (t (error "bad function spec ~S" function-spec))))
   (defun undefine-functions (function-spec-list)
-    (map () 'undefine-function function-spec-list)))
-
-(macrolet
-    ((defdef (def* def)
-       `(defmacro ,def* (name formals &rest rest)
-          (destructuring-bind (name &key (supersede t))
-              (if (or (atom name) (eq (car name) 'setf))
-                  (list name :supersede nil)
-                  name)
-            (declare (ignorable supersede))
-            `(progn
-             ;; undefining the previous function is the portable way
-             ;; of overriding any incompatible previous gf, except on CLISP.
-             ;; We usually try to do it only for the functions that need it,
-             ;; which happens in asdf/upgrade - however, for ECL, we need this hammer,
-             ;; (which causes issues in clisp)
-               ,@(when (or #-clisp supersede #+(or ecl gcl2.7) t) ; XXX
-                   `((undefine-function ',name)))
-               #-gcl ; gcl 2.7.0 notinline functions lose secondary return values :-(
-               ,@(when (and #+ecl (symbolp name)) ; fails for setf functions on ecl
-                   `((declaim (notinline ,name))))
-               (,',def ,name ,formals , at rest))))))
-  (defdef defgeneric* defgeneric)
-  (defdef defun* defun))
-
+    (map () 'undefine-function function-spec-list))
+  (macrolet
+      ((defdef (def* def)
+         `(defmacro ,def* (name formals &rest rest)
+            (destructuring-bind (name &key (supersede t))
+                (if (or (atom name) (eq (car name) 'setf))
+                    (list name :supersede nil)
+                    name)
+              (declare (ignorable supersede))
+              `(progn
+                 ;; undefining the previous function is the portable way
+                 ;; of overriding any incompatible previous gf, except on CLISP.
+                 ;; We usually try to do it only for the functions that need it,
+                 ;; which happens in asdf/upgrade - however, for ECL, we need this hammer,
+                 ;; (which causes issues in clisp)
+                 ,@(when (or #-clisp supersede #+(or ecl gcl2.7) t) ; XXX
+                     `((undefine-function ',name)))
+                 #-gcl ; gcl 2.7.0 notinline functions lose secondary return values :-(
+                 ,@(when (and #+ecl (symbolp name)) ; fails for setf functions on ecl
+                     `((declaim (notinline ,name))))
+                 (,',def ,name ,formals , at rest))))))
+    (defdef defgeneric* defgeneric)
+    (defdef defun* defun))
+  (defmacro with-upgradability ((&optional) &body body)
+    `(eval-when (:compile-toplevel :load-toplevel :execute)
+       ,@(loop :for form :in body :collect
+               (if (consp form)
+                   (destructuring-bind (car . cdr) form
+                     (case car
+                       ((defun) `(defun* , at cdr))
+                       ((defgeneric)
+                        (unless (or #+gcl2.6 (and (consp (car cdr)) (eq 'setf (caar cdr))))
+                          `(defgeneric* , at cdr)))
+                       (otherwise form)))
+                   form)))))
 
 ;;; Magic debugging help. See contrib/debug.lisp
-(defvar *asdf-debug-utility*
-  '(or (ignore-errors
-        (symbol-call :asdf :system-relative-pathname :asdf-driver "contrib/debug.lisp"))
-    (merge-pathnames "cl/asdf/contrib/debug.lisp" (user-homedir-pathname)))
-  "form that evaluates to the pathname to your favorite debugging utilities")
-
-(defmacro asdf-debug (&rest keys)
-  `(eval-when (:compile-toplevel :load-toplevel :execute)
-     (load-asdf-debug-utility , at keys)))
-
-(defun* load-asdf-debug-utility (&key package utility-file)
-  (let* ((*package* (if package (find-package package) *package*))
-         (keyword (read-from-string
-                   (format nil ":DBG-~:@(~A~)" (package-name *package*)))))
-    (unless (member keyword *features*)
-      (let* ((utility-file (or utility-file *asdf-debug-utility*))
-             (file (ignore-errors (probe-file (eval utility-file)))))
-        (if file (load file)
-            (error "Failed to locate debug utility file: ~S" utility-file))))))
+(with-upgradability ()
+  (defvar *asdf-debug-utility*
+    '(or (ignore-errors
+          (symbol-call :asdf :system-relative-pathname :asdf-driver "contrib/debug.lisp"))
+      (merge-pathnames "cl/asdf/contrib/debug.lisp" (user-homedir-pathname)))
+    "form that evaluates to the pathname to your favorite debugging utilities")
+
+  (defmacro asdf-debug (&rest keys)
+    `(eval-when (:compile-toplevel :load-toplevel :execute)
+       (load-asdf-debug-utility , at keys)))
+
+  (defun load-asdf-debug-utility (&key package utility-file)
+    (let* ((*package* (if package (find-package package) *package*))
+           (keyword (read-from-string
+                     (format nil ":DBG-~:@(~A~)" (package-name *package*)))))
+      (unless (member keyword *features*)
+        (let* ((utility-file (or utility-file *asdf-debug-utility*))
+               (file (ignore-errors (probe-file (eval utility-file)))))
+          (if file (load file)
+              (error "Failed to locate debug utility file: ~S" utility-file)))))))
 
 
 ;;; Flow control
-(defmacro if-let (bindings &body (then-form &optional else-form)) ;; from alexandria
-  ;; bindings can be (var form) or ((var1 form1) ...)
-  (let* ((binding-list (if (and (consp bindings) (symbolp (car bindings)))
-                           (list bindings)
-                           bindings))
-         (variables (mapcar #'car binding-list)))
-    `(let ,binding-list
-       (if (and , at variables)
-           ,then-form
-           ,else-form))))
+(with-upgradability ()
+  (defmacro if-let (bindings &body (then-form &optional else-form)) ;; from alexandria
+    ;; bindings can be (var form) or ((var1 form1) ...)
+    (let* ((binding-list (if (and (consp bindings) (symbolp (car bindings)))
+                             (list bindings)
+                             bindings))
+           (variables (mapcar #'car binding-list)))
+      `(let ,binding-list
+         (if (and , at variables)
+             ,then-form
+             ,else-form)))))
 
 ;;; List manipulation
-(defmacro while-collecting ((&rest collectors) &body body)
-  "COLLECTORS should be a list of names for collections.  A collector
+(with-upgradability ()
+  (defmacro while-collecting ((&rest collectors) &body body)
+    "COLLECTORS should be a list of names for collections.  A collector
 defines a function that, when applied to an argument inside BODY, will
 add its argument to the corresponding collection.  Returns multiple values,
 a list for each collection, in order.
@@ -1023,135 +1101,143 @@
              \(foo \(first x\)\)
              \(bar \(second x\)\)\)\)
 Returns two values: \(A B C\) and \(1 2 3\)."
-  (let ((vars (mapcar #'(lambda (x) (gensym (symbol-name x))) collectors))
-        (initial-values (mapcar (constantly nil) collectors)))
-    `(let ,(mapcar #'list vars initial-values)
-       (flet ,(mapcar #'(lambda (c v) `(,c (x) (push x ,v) (values))) collectors vars)
-         , at body
-         (values ,@(mapcar #'(lambda (v) `(reverse ,v)) vars))))))
-
-(define-modify-macro appendf (&rest args)
-  append "Append onto list") ;; only to be used on short lists.
-
-(defun* length=n-p (x n) ;is it that (= (length x) n) ?
-  (check-type n (integer 0 *))
-  (loop
-    :for l = x :then (cdr l)
-    :for i :downfrom n :do
-    (cond
-      ((zerop i) (return (null l)))
-      ((not (consp l)) (return nil)))))
+    (let ((vars (mapcar #'(lambda (x) (gensym (symbol-name x))) collectors))
+          (initial-values (mapcar (constantly nil) collectors)))
+      `(let ,(mapcar #'list vars initial-values)
+         (flet ,(mapcar #'(lambda (c v) `(,c (x) (push x ,v) (values))) collectors vars)
+           , at body
+           (values ,@(mapcar #'(lambda (v) `(reverse ,v)) vars))))))
+
+  (define-modify-macro appendf (&rest args)
+    append "Append onto list") ;; only to be used on short lists.
+
+  (defun length=n-p (x n) ;is it that (= (length x) n) ?
+    (check-type n (integer 0 *))
+    (loop
+      :for l = x :then (cdr l)
+      :for i :downfrom n :do
+        (cond
+          ((zerop i) (return (null l)))
+          ((not (consp l)) (return nil))))))
 
 ;;; remove a key from a plist, i.e. for keyword argument cleanup
-(defun* remove-plist-key (key plist)
-  "Remove a single key from a plist"
-  (loop* :for (k v) :on plist :by #'cddr
-    :unless (eq k key)
-    :append (list k v)))
-
-(defun* remove-plist-keys (keys plist)
-  "Remove a list of keys from a plist"
-  (loop* :for (k v) :on plist :by #'cddr
-    :unless (member k keys)
-    :append (list k v)))
+(with-upgradability ()
+  (defun remove-plist-key (key plist)
+    "Remove a single key from a plist"
+    (loop* :for (k v) :on plist :by #'cddr
+           :unless (eq k key)
+           :append (list k v)))
+
+  (defun remove-plist-keys (keys plist)
+    "Remove a list of keys from a plist"
+    (loop* :for (k v) :on plist :by #'cddr
+           :unless (member k keys)
+           :append (list k v))))
 
 
 ;;; Sequences
-(defun* emptyp (x)
-  "Predicate that is true for an empty sequence"
-  (or (null x) (and (vectorp x) (zerop (length x)))))
+(with-upgradability ()
+  (defun emptyp (x)
+    "Predicate that is true for an empty sequence"
+    (or (null x) (and (vectorp x) (zerop (length x))))))
 
 
 ;;; Strings
-(defun* strcat (&rest strings)
-  (apply 'concatenate 'string strings))
+(with-upgradability ()
+  (defun strcat (&rest strings)
+    (apply 'concatenate 'string strings))
 
-(defun* first-char (s)
-  (and (stringp s) (plusp (length s)) (char s 0)))
+  (defun first-char (s)
+    (and (stringp s) (plusp (length s)) (char s 0)))
 
-(defun* last-char (s)
-  (and (stringp s) (plusp (length s)) (char s (1- (length s)))))
+  (defun last-char (s)
+    (and (stringp s) (plusp (length s)) (char s (1- (length s)))))
 
-(defun* split-string (string &key max (separator '(#\Space #\Tab)))
-  "Split STRING into a list of components separated by
+  (defun split-string (string &key max (separator '(#\Space #\Tab)))
+    "Split STRING into a list of components separated by
 any of the characters in the sequence SEPARATOR.
 If MAX is specified, then no more than max(1,MAX) components will be returned,
 starting the separation from the end, e.g. when called with arguments
  \"a.b.c.d.e\" :max 3 :separator \".\" it will return (\"a.b.c\" \"d\" \"e\")."
-  (block ()
-    (let ((list nil) (words 0) (end (length string)))
-      (flet ((separatorp (char) (find char separator))
-             (done () (return (cons (subseq string 0 end) list))))
-        (loop
-          :for start = (if (and max (>= words (1- max)))
-                           (done)
-                           (position-if #'separatorp string :end end :from-end t)) :do
-          (when (null start)
-            (done))
-          (push (subseq string (1+ start) end) list)
-          (incf words)
-          (setf end start))))))
-
-(defun* string-prefix-p (prefix string)
-  "Does STRING begin with PREFIX?"
-  (let* ((x (string prefix))
-         (y (string string))
-         (lx (length x))
-         (ly (length y)))
-    (and (<= lx ly) (string= x y :end2 lx))))
-
-(defun* string-suffix-p (string suffix)
-  "Does STRING end with SUFFIX?"
-  (let* ((x (string string))
-         (y (string suffix))
-         (lx (length x))
-         (ly (length y)))
-    (and (<= ly lx) (string= x y :start1 (- lx ly)))))
-
-(defun* string-enclosed-p (prefix string suffix)
-  "Does STRING begin with PREFIX and end with SUFFIX?"
-  (and (string-prefix-p prefix string)
-       (string-suffix-p string suffix)))
+    (block ()
+      (let ((list nil) (words 0) (end (length string)))
+        (flet ((separatorp (char) (find char separator))
+               (done () (return (cons (subseq string 0 end) list))))
+          (loop
+            :for start = (if (and max (>= words (1- max)))
+                             (done)
+                             (position-if #'separatorp string :end end :from-end t)) :do
+                               (when (null start)
+                                 (done))
+                               (push (subseq string (1+ start) end) list)
+                               (incf words)
+                               (setf end start))))))
+
+  (defun string-prefix-p (prefix string)
+    "Does STRING begin with PREFIX?"
+    (let* ((x (string prefix))
+           (y (string string))
+           (lx (length x))
+           (ly (length y)))
+      (and (<= lx ly) (string= x y :end2 lx))))
+
+  (defun string-suffix-p (string suffix)
+    "Does STRING end with SUFFIX?"
+    (let* ((x (string string))
+           (y (string suffix))
+           (lx (length x))
+           (ly (length y)))
+      (and (<= ly lx) (string= x y :start1 (- lx ly)))))
+
+  (defun string-enclosed-p (prefix string suffix)
+    "Does STRING begin with PREFIX and end with SUFFIX?"
+    (and (string-prefix-p prefix string)
+         (string-suffix-p string suffix))))
 
 
 ;;; CLOS
-(defun* find-class* (x &optional (errorp t) environment)
-  (etypecase x
-    ((or standard-class built-in-class) x)
-    #+gcl2.6 (keyword nil)
-    (symbol (find-class x errorp environment))))
+(with-upgradability ()
+  (defun find-class* (x &optional (errorp t) environment)
+    (etypecase x
+      ((or standard-class built-in-class) x)
+      #+gcl2.6 (keyword nil)
+      (symbol (find-class x errorp environment)))))
 
 
 ;;; stamps: a REAL or boolean where NIL=-infinity, T=+infinity
-(deftype stamp () '(or real boolean))
-(defun* stamp< (x y)
-  (etypecase x
-    (null (and y t))
-    ((eql t) nil)
-    (real (etypecase y
-            (null nil)
-            ((eql t) t)
-            (real (< x y))))))
-(defun* stamps< (list) (loop :for y :in list :for x = nil :then y :always (stamp< x y)))
-(defun* stamp*< (&rest list) (stamps< list))
-(defun* stamp<= (x y) (not (stamp< y x)))
-(defun* earlier-stamp (x y) (if (stamp< x y) x y))
-(defun* stamps-earliest (list) (reduce 'earlier-stamp list :initial-value t))
-(defun* earliest-stamp (&rest list) (stamps-earliest list))
-(defun* later-stamp (x y) (if (stamp< x y) y x))
-(defun* stamps-latest (list) (reduce 'later-stamp list :initial-value nil))
-(defun* latest-stamp (&rest list) (stamps-latest list))
-(define-modify-macro latest-stamp-f (&rest stamps) latest-stamp)
+(eval-when (#-lispworks :compile-toplevel :load-toplevel :execute)
+  (deftype stamp () '(or real boolean)))
+(with-upgradability ()
+  (defun stamp< (x y)
+    (etypecase x
+      (null (and y t))
+      ((eql t) nil)
+      (real (etypecase y
+              (null nil)
+              ((eql t) t)
+              (real (< x y))))))
+  (defun stamps< (list) (loop :for y :in list :for x = nil :then y :always (stamp< x y)))
+  (defun stamp*< (&rest list) (stamps< list))
+  (defun stamp<= (x y) (not (stamp< y x)))
+  (defun earlier-stamp (x y) (if (stamp< x y) x y))
+  (defun stamps-earliest (list) (reduce 'earlier-stamp list :initial-value t))
+  (defun earliest-stamp (&rest list) (stamps-earliest list))
+  (defun later-stamp (x y) (if (stamp< x y) y x))
+  (defun stamps-latest (list) (reduce 'later-stamp list :initial-value nil))
+  (defun latest-stamp (&rest list) (stamps-latest list))
+  (define-modify-macro latest-stamp-f (&rest stamps) latest-stamp))
 
 
 ;;; Hash-tables
-(defun* list-to-hash-set (list &aux (h (make-hash-table :test 'equal)))
-  (dolist (x list h) (setf (gethash x h) t)))
+(with-upgradability ()
+  (defun list-to-hash-set (list &aux (h (make-hash-table :test 'equal)))
+    (dolist (x list h) (setf (gethash x h) t))))
 
 
 ;;; Function designators
-(defun* ensure-function (fun &key (package :cl))
-  "Coerce the object FUN into a function.
+(with-upgradability ()
+  (defun ensure-function (fun &key (package :cl))
+    "Coerce the object FUN into a function.
 
 If FUN is a FUNCTION, return it.
 If the FUN is a non-sequence literal constant, return constantly that,
@@ -1161,17 +1247,17 @@
 to the appended list of the rest of its CDR and the arguments.
 If FUN is a string, READ a form from it in the specified PACKAGE (default: CL)
 and EVAL that in a (FUNCTION ...) context."
-  (etypecase fun
-    (function fun)
-    ((or boolean keyword character number pathname) (constantly fun))
-    ((or function symbol) fun)
-    (cons #'(lambda (&rest args) (apply (car fun) (append (cdr fun) args))))
-    (string (eval `(function ,(with-standard-io-syntax
-                                (let ((*package* (find-package package)))
-                                  (read-from-string fun))))))))
+    (etypecase fun
+      (function fun)
+      ((or boolean keyword character number pathname) (constantly fun))
+      ((or function symbol) fun)
+      (cons #'(lambda (&rest args) (apply (car fun) (append (cdr fun) args))))
+      (string (eval `(function ,(with-standard-io-syntax
+                                  (let ((*package* (find-package package)))
+                                    (read-from-string fun))))))))
 
-(defun* access-at (object at)
-  "Given an OBJECT and an AT specifier, list of successive accessors,
+  (defun access-at (object at)
+    "Given an OBJECT and an AT specifier, list of successive accessors,
 call each accessor on the result of the previous calls.
 An accessor may be an integer, meaning a call to ELT,
 a keyword, meaning a call to GETF,
@@ -1180,45 +1266,46 @@
 or a list of a function designator and arguments, interpreted as per ENSURE-FUNCTION.
 As a degenerate case, the AT specifier may be an atom of a single such accessor
 instead of a list."
-  (flet ((access (object accessor)
-           (etypecase accessor
-             (function (funcall accessor object))
-             (integer (elt object accessor))
-             (keyword (getf object accessor))
-             (null object)
-             (symbol (funcall accessor object))
-             (cons (funcall (ensure-function accessor) object)))))
-    (if (listp at)
-        (dolist (accessor at object)
-          (setf object (access object accessor)))
-        (access object at))))
+    (flet ((access (object accessor)
+             (etypecase accessor
+               (function (funcall accessor object))
+               (integer (elt object accessor))
+               (keyword (getf object accessor))
+               (null object)
+               (symbol (funcall accessor object))
+               (cons (funcall (ensure-function accessor) object)))))
+      (if (listp at)
+          (dolist (accessor at object)
+            (setf object (access object accessor)))
+          (access object at))))
 
-(defun* access-at-count (at)
-  "From an AT specification, extract a COUNT of maximum number
+  (defun access-at-count (at)
+    "From an AT specification, extract a COUNT of maximum number
    of sub-objects to read as per ACCESS-AT"
-  (cond
-    ((integerp at)
-     (1+ at))
-    ((and (consp at) (integerp (first at)))
-     (1+ (first at)))))
-
-(defun* call-function (function-spec &rest arguments)
-  (apply (ensure-function function-spec) arguments))
-
-(defun* call-functions (function-specs)
-  (map () 'call-function function-specs))
-
-(defun* register-hook-function (variable hook &optional (call-now-p t))
-  (pushnew hook (symbol-value variable))
-  (when call-now-p (call-function hook)))
+    (cond
+      ((integerp at)
+       (1+ at))
+      ((and (consp at) (integerp (first at)))
+       (1+ (first at)))))
+
+  (defun call-function (function-spec &rest arguments)
+    (apply (ensure-function function-spec) arguments))
+
+  (defun call-functions (function-specs)
+    (map () 'call-function function-specs))
+
+  (defun register-hook-function (variable hook &optional call-now-p)
+    (pushnew hook (symbol-value variable))
+    (when call-now-p (call-function hook))))
 
 
 ;;; Version handling
-(defun* unparse-version (version-list)
-  (format nil "~{~D~^.~}" version-list))
+(with-upgradability ()
+  (defun unparse-version (version-list)
+    (format nil "~{~D~^.~}" version-list))
 
-(defun* parse-version (version-string &optional on-error)
-  "Parse a VERSION-STRING as a series of natural integers separated by dots.
+  (defun parse-version (version-string &optional on-error)
+    "Parse a VERSION-STRING as a series of natural integers separated by dots.
 Return a (non-null) list of integers if the string is valid;
 otherwise return NIL.
 
@@ -1226,85 +1313,96 @@
 with format arguments explaining why the version is invalid.
 ON-ERROR is also called if the version is not canonical
 in that it doesn't print back to itself, but the list is returned anyway."
-  (block nil
-   (unless (stringp version-string)
-     (call-function on-error "~S: ~S is not a string" 'parse-version version-string)
-     (return))
-   (unless (loop :for prev = nil :then c :for c :across version-string
-                 :always (or (digit-char-p c)
-                             (and (eql c #\.) prev (not (eql prev #\.))))
-                 :finally (return (and c (digit-char-p c))))
-     (call-function on-error "~S: ~S doesn't follow asdf version numbering convention"
-                    'parse-version version-string)
-     (return))
-   (let* ((version-list
-            (mapcar #'parse-integer (split-string version-string :separator ".")))
-          (normalized-version (unparse-version version-list)))
-     (unless (equal version-string normalized-version)
-       (call-function on-error "~S: ~S contains leading zeros" 'parse-version version-string))
-     version-list)))
+    (block nil
+      (unless (stringp version-string)
+        (call-function on-error "~S: ~S is not a string" 'parse-version version-string)
+        (return))
+      (unless (loop :for prev = nil :then c :for c :across version-string
+                    :always (or (digit-char-p c)
+                                (and (eql c #\.) prev (not (eql prev #\.))))
+                    :finally (return (and c (digit-char-p c))))
+        (call-function on-error "~S: ~S doesn't follow asdf version numbering convention"
+                       'parse-version version-string)
+        (return))
+      (let* ((version-list
+               (mapcar #'parse-integer (split-string version-string :separator ".")))
+             (normalized-version (unparse-version version-list)))
+        (unless (equal version-string normalized-version)
+          (call-function on-error "~S: ~S contains leading zeros" 'parse-version version-string))
+        version-list)))
+
+  (defun lexicographic< (< x y)
+    (cond ((null y) nil)
+          ((null x) t)
+          ((funcall < (car x) (car y)) t)
+          ((funcall < (car y) (car x)) nil)
+          (t (lexicographic< < (cdr x) (cdr y)))))
+
+  (defun lexicographic<= (< x y)
+    (not (lexicographic< < y x)))
+
+  (defun version< (version1 version2)
+    (let ((v1 (parse-version version1 nil))
+          (v2 (parse-version version2 nil)))
+      (lexicographic< '< v1 v2)))
 
+  (defun version<= (version1 version2)
+    (not (version< version2 version1)))
 
-(defun* version-compatible-p (provided-version required-version)
-  "Is the provided version a compatible substitution for the required-version?
+  (defun version-compatible-p (provided-version required-version)
+    "Is the provided version a compatible substitution for the required-version?
 If major versions differ, it's not compatible.
 If they are equal, then any later version is compatible,
 with later being determined by a lexicographical comparison of minor numbers."
-  (let ((x (parse-version provided-version 'warn))
-        (y (parse-version required-version 'warn)))
-    (labels ((bigger (x y)
-               (cond ((not y) t)
-                     ((not x) nil)
-                     ((> (car x) (car y)) t)
-                     ((= (car x) (car y))
-                      (bigger (cdr x) (cdr y))))))
-      (and x y (= (car x) (car y))
-           (or (not (cdr y)) (bigger (cdr x) (cdr y)))))))
+    (let ((x (parse-version provided-version nil))
+          (y (parse-version required-version nil)))
+      (and x y (= (car x) (car y)) (lexicographic<= '< (cdr y) (cdr x))))))
 
 
 ;;; Condition control
 
-(defvar *uninteresting-conditions* nil
-  "Uninteresting conditions, as per MATCH-CONDITION-P")
+(with-upgradability ()
+  (defvar *uninteresting-conditions* nil
+    "Uninteresting conditions, as per MATCH-CONDITION-P")
+
+  (defparameter +simple-condition-format-control-slot+
+    #+abcl 'system::format-control
+    #+allegro 'excl::format-control
+    #+clisp 'system::$format-control
+    #+clozure 'ccl::format-control
+    #+(or cmu scl) 'conditions::format-control
+    #+ecl 'si::format-control
+    #+(or gcl lispworks) 'conditions::format-string
+    #+sbcl 'sb-kernel:format-control
+    #-(or abcl allegro clisp clozure cmu ecl gcl lispworks sbcl scl) nil
+    "Name of the slot for FORMAT-CONTROL in simple-condition")
 
-(defparameter +simple-condition-format-control-slot+
-  #+abcl 'system::format-control
-  #+allegro 'excl::format-control
-  #+clisp 'system::$format-control
-  #+clozure 'ccl::format-control
-  #+ecl 'si::format-control
-  #+(or cmu scl) 'conditions::format-control
-  #+(or gcl lispworks) 'conditions::format-string
-  #+sbcl 'sb-kernel:format-control
-  #-(or abcl allegro clisp clozure cmu ecl gcl lispworks sbcl scl) nil
-  "Name of the slot for FORMAT-CONTROL in simple-condition")
-
-(defun* match-condition-p (x condition)
-  "Compare received CONDITION to some pattern X:
+  (defun match-condition-p (x condition)
+    "Compare received CONDITION to some pattern X:
 a symbol naming a condition class,
 a simple vector of length 2, arguments to find-symbol* with result as above,
 or a string describing the format-control of a simple-condition."
-  (etypecase x
-    (symbol (typep condition x))
-    ((simple-vector 2) (typep condition (find-symbol* (svref x 0) (svref x 1) nil)))
-    (function (funcall x condition))
-    (string (and (typep condition 'simple-condition)
-                 ;; On SBCL, it's always set and the check triggers a warning
-                 #+(or allegro clozure cmu lispworks scl)
-		 (slot-boundp condition +simple-condition-format-control-slot+)
-                 (ignore-errors (equal (simple-condition-format-control condition) x))))))
-
-(defun* match-any-condition-p (condition conditions)
-  "match CONDITION against any of the patterns of CONDITIONS supplied"
-  (loop :for x :in conditions :thereis (match-condition-p x condition)))
-
-(defun* call-with-muffled-conditions (thunk conditions)
-  (handler-bind ((t #'(lambda (c) (when (match-any-condition-p c conditions)
-                                    (muffle-warning c)))))
-    (funcall thunk)))
+    (etypecase x
+      (symbol (typep condition x))
+      ((simple-vector 2) (typep condition (find-symbol* (svref x 0) (svref x 1) nil)))
+      (function (funcall x condition))
+      (string (and (typep condition 'simple-condition)
+                   ;; On SBCL, it's always set and the check triggers a warning
+                   #+(or allegro clozure cmu lispworks scl)
+                   (slot-boundp condition +simple-condition-format-control-slot+)
+                   (ignore-errors (equal (simple-condition-format-control condition) x))))))
+
+  (defun match-any-condition-p (condition conditions)
+    "match CONDITION against any of the patterns of CONDITIONS supplied"
+    (loop :for x :in conditions :thereis (match-condition-p x condition)))
+
+  (defun call-with-muffled-conditions (thunk conditions)
+    (handler-bind ((t #'(lambda (c) (when (match-any-condition-p c conditions)
+                                      (muffle-warning c)))))
+      (funcall thunk)))
 
-(defmacro with-muffled-uninteresting-conditions ((conditions) &body body)
-  `(call-with-muffled-uninteresting-conditions #'(lambda () , at body) ,conditions))
+  (defmacro with-muffled-uninteresting-conditions ((conditions) &body body)
+    `(call-with-muffled-uninteresting-conditions #'(lambda () , at body) ,conditions)))
 
 
 ;;;; ---------------------------------------------------------------------------
@@ -1326,8 +1424,8 @@
 (in-package :asdf/os)
 
 ;;; Features
-(eval-when (:compile-toplevel :load-toplevel :execute)
-  (defun* featurep (x &optional (*features* *features*))
+(with-upgradability ()
+  (defun featurep (x &optional (*features* *features*))
     (cond
       ((atom x) (and (member x *features*) t))
       ((eq :not (car x)) (assert (null (cddr x))) (not (featurep (cadr x))))
@@ -1335,18 +1433,18 @@
       ((eq :and (car x)) (every #'featurep (cdr x)))
       (t (error "Malformed feature specification ~S" x))))
 
-  (defun* os-unix-p ()
+  (defun os-unix-p ()
     (or #+abcl (featurep :unix)
         #+(and (not abcl) (or unix cygwin darwin)) t))
 
-  (defun* os-windows-p ()
+  (defun os-windows-p ()
     (or #+abcl (featurep :windows)
         #+(and (not (or unix cygwin darwin)) (or win32 windows mswindows mingw32)) t))
 
-  (defun* os-genera-p ()
+  (defun os-genera-p ()
     (or #+genera t))
 
-  (defun* detect-os ()
+  (defun detect-os ()
     (flet ((yes (yes) (pushnew yes *features*))
            (no (no) (setf *features* (remove no *features*))))
       (cond
@@ -1360,38 +1458,39 @@
 
 ;;;; Environment variables: getting them, and parsing them.
 
-(defun* getenv (x)
-  (declare (ignorable x))
-  #+(or abcl clisp ecl xcl) (ext:getenv x)
-  #+allegro (sys:getenv x)
-  #+clozure (ccl:getenv x)
-  #+(or cmu scl) (cdr (assoc x ext:*environment-list* :test #'string=))
-  #+cormanlisp
-  (let* ((buffer (ct:malloc 1))
-         (cname (ct:lisp-string-to-c-string x))
-         (needed-size (win:getenvironmentvariable cname buffer 0))
-         (buffer1 (ct:malloc (1+ needed-size))))
-    (prog1 (if (zerop (win:getenvironmentvariable cname buffer1 needed-size))
-               nil
-               (ct:c-string-to-lisp-string buffer1))
-      (ct:free buffer)
-      (ct:free buffer1)))
-  #+gcl (system:getenv x)
-  #+genera nil
-  #+lispworks (lispworks:environment-variable x)
-  #+mcl (ccl:with-cstrs ((name x))
-          (let ((value (_getenv name)))
-            (unless (ccl:%null-ptr-p value)
-              (ccl:%get-cstring value))))
-  #+mkcl (#.(or (find-symbol* 'getenv :si nil) (find-symbol* 'getenv :mk-ext nil)) x)
-  #+sbcl (sb-ext:posix-getenv x)
-  #-(or abcl allegro clisp clozure cmu cormanlisp ecl gcl genera lispworks mcl mkcl sbcl scl xcl)
-  (error "~S is not supported on your implementation" 'getenv))
+(with-upgradability ()
+  (defun getenv (x)
+    (declare (ignorable x))
+    #+(or abcl clisp ecl xcl) (ext:getenv x)
+    #+allegro (sys:getenv x)
+    #+clozure (ccl:getenv x)
+    #+(or cmu scl) (cdr (assoc x ext:*environment-list* :test #'string=))
+    #+cormanlisp
+    (let* ((buffer (ct:malloc 1))
+           (cname (ct:lisp-string-to-c-string x))
+           (needed-size (win:getenvironmentvariable cname buffer 0))
+           (buffer1 (ct:malloc (1+ needed-size))))
+      (prog1 (if (zerop (win:getenvironmentvariable cname buffer1 needed-size))
+                 nil
+                 (ct:c-string-to-lisp-string buffer1))
+        (ct:free buffer)
+        (ct:free buffer1)))
+    #+gcl (system:getenv x)
+    #+genera nil
+    #+lispworks (lispworks:environment-variable x)
+    #+mcl (ccl:with-cstrs ((name x))
+            (let ((value (_getenv name)))
+              (unless (ccl:%null-ptr-p value)
+                (ccl:%get-cstring value))))
+    #+mkcl (#.(or (find-symbol* 'getenv :si nil) (find-symbol* 'getenv :mk-ext nil)) x)
+    #+sbcl (sb-ext:posix-getenv x)
+    #-(or abcl allegro clisp clozure cmu cormanlisp ecl gcl genera lispworks mcl mkcl sbcl scl xcl)
+    (error "~S is not supported on your implementation" 'getenv))
 
-(defun* getenvp (x)
-  "Predicate that is true if the named variable is present in the libc environment,
+  (defun getenvp (x)
+    "Predicate that is true if the named variable is present in the libc environment,
 then returning the non-empty string value of the variable"
-  (let ((g (getenv x))) (and (not (emptyp g)) g)))
+    (let ((g (getenv x))) (and (not (emptyp g)) g))))
 
 
 ;;;; implementation-identifier
@@ -1400,146 +1499,156 @@
 ;; Initially stolen from SLIME's SWANK, completely rewritten since.
 ;; We're back to runtime checking, for the sake of e.g. ABCL.
 
-(defun* first-feature (feature-sets)
-  (dolist (x feature-sets)
-    (multiple-value-bind (short long feature-expr)
-        (if (consp x)
-            (values (first x) (second x) (cons :or (rest x)))
-            (values x x x))
-      (when (featurep feature-expr)
-        (return (values short long))))))
-
-(defun* implementation-type ()
-  (first-feature
-   '(:abcl (:acl :allegro) (:ccl :clozure) :clisp (:corman :cormanlisp)
-     (:cmu :cmucl :cmu) :ecl :gcl
-     (:lwpe :lispworks-personal-edition) (:lw :lispworks)
-     :mcl :mkcl :sbcl :scl (:smbx :symbolics) :xcl)))
-
-(defvar *implementation-type* (implementation-type))
-
-(defun* operating-system ()
-  (first-feature
-   '(:cygwin (:win :windows :mswindows :win32 :mingw32) ;; try cygwin first!
-     (:linux :linux :linux-target) ;; for GCL at least, must appear before :bsd
-     (:macosx :macosx :darwin :darwin-target :apple) ; also before :bsd
-     (:solaris :solaris :sunos) (:bsd :bsd :freebsd :netbsd :openbsd) :unix
-     :genera)))
-
-(defun* architecture ()
-  (first-feature
-   '((:x64 :x86-64 :x86_64 :x8664-target :amd64 (:and :word-size=64 :pc386))
-     (:x86 :x86 :i386 :i486 :i586 :i686 :pentium3 :pentium4 :pc386 :iapx386 :x8632-target)
-     (:ppc64 :ppc64 :ppc64-target) (:ppc32 :ppc32 :ppc32-target :ppc :powerpc)
-     :hppa64 :hppa :sparc64 (:sparc32 :sparc32 :sparc)
-     :mipsel :mipseb :mips :alpha (:arm :arm :arm-target) :imach
-     ;; Java comes last: if someone uses C via CFFI or otherwise JNA or JNI,
-     ;; we may have to segregate the code still by architecture.
-     (:java :java :java-1.4 :java-1.5 :java-1.6 :java-1.7))))
-
-#+clozure
-(defun* ccl-fasl-version ()
-  ;; the fasl version is target-dependent from CCL 1.8 on.
-  (or (let ((s 'ccl::target-fasl-version))
-        (and (fboundp s) (funcall s)))
-      (and (boundp 'ccl::fasl-version)
-           (symbol-value 'ccl::fasl-version))
-      (error "Can't determine fasl version.")))
-
-(defun* lisp-version-string ()
-  (let ((s (lisp-implementation-version)))
-    (car ; as opposed to OR, this idiom prevents some unreachable code warning
-     (list
-      #+allegro
-      (format nil "~A~@[~A~]~@[~A~]~@[~A~]"
-              excl::*common-lisp-version-number*
-              ;; M means "modern", as opposed to ANSI-compatible mode (which I consider default)
-              (and (eq excl:*current-case-mode* :case-sensitive-lower) "M")
-              ;; Note if not using International ACL
-              ;; see http://www.franz.com/support/documentation/8.1/doc/operators/excl/ics-target-case.htm
-              (excl:ics-target-case (:-ics "8"))
-              (and (member :smp *features*) "S"))
-      #+armedbear (format nil "~a-fasl~a" s system::*fasl-version*)
-      #+clisp
-      (subseq s 0 (position #\space s)) ; strip build information (date, etc.)
-      #+clozure
-      (format nil "~d.~d-f~d" ; shorten for windows
-              ccl::*openmcl-major-version*
-              ccl::*openmcl-minor-version*
-              (logand (ccl-fasl-version) #xFF))
-      #+cmu (substitute #\- #\/ s)
-      #+scl (format nil "~A~A" s
-                    ;; ANSI upper case vs lower case.
-                    (ecase ext:*case-mode* (:upper "") (:lower "l")))
-      #+ecl (format nil "~A~@[-~A~]" s
-                    (let ((vcs-id (ext:lisp-implementation-vcs-id)))
-                      (subseq vcs-id 0 (min (length vcs-id) 8))))
-      #+gcl (subseq s (1+ (position #\space s)))
-      #+genera
-      (multiple-value-bind (major minor) (sct:get-system-version "System")
-        (format nil "~D.~D" major minor))
-      #+mcl (subseq s 8) ; strip the leading "Version "
-      s))))
-
-(defun* implementation-identifier ()
-  (substitute-if
-   #\_ #'(lambda (x) (find x " /:;&^\\|?<>(){}[]$#`'\""))
-   (format nil "~(~a~@{~@[-~a~]~}~)"
-           (or (implementation-type) (lisp-implementation-type))
-           (or (lisp-version-string) (lisp-implementation-version))
-           (or (operating-system) (software-type))
-           (or (architecture) (machine-type)))))
+(with-upgradability ()
+  (defun first-feature (feature-sets)
+    (dolist (x feature-sets)
+      (multiple-value-bind (short long feature-expr)
+          (if (consp x)
+              (values (first x) (second x) (cons :or (rest x)))
+              (values x x x))
+        (when (featurep feature-expr)
+          (return (values short long))))))
+
+  (defun implementation-type ()
+    (first-feature
+     '(:abcl (:acl :allegro) (:ccl :clozure) :clisp (:corman :cormanlisp)
+       (:cmu :cmucl :cmu) :ecl :gcl
+       (:lwpe :lispworks-personal-edition) (:lw :lispworks)
+       :mcl :mkcl :sbcl :scl (:smbx :symbolics) :xcl)))
+
+  (defvar *implementation-type* (implementation-type))
+
+  (defun operating-system ()
+    (first-feature
+     '(:cygwin (:win :windows :mswindows :win32 :mingw32) ;; try cygwin first!
+       (:linux :linux :linux-target) ;; for GCL at least, must appear before :bsd
+       (:macosx :macosx :darwin :darwin-target :apple) ; also before :bsd
+       (:solaris :solaris :sunos) (:bsd :bsd :freebsd :netbsd :openbsd) :unix
+       :genera)))
+
+  (defun architecture ()
+    (first-feature
+     '((:x64 :x86-64 :x86_64 :x8664-target :amd64 (:and :word-size=64 :pc386))
+       (:x86 :x86 :i386 :i486 :i586 :i686 :pentium3 :pentium4 :pc386 :iapx386 :x8632-target)
+       (:ppc64 :ppc64 :ppc64-target) (:ppc32 :ppc32 :ppc32-target :ppc :powerpc)
+       :hppa64 :hppa :sparc64 (:sparc32 :sparc32 :sparc)
+       :mipsel :mipseb :mips :alpha (:arm :arm :arm-target) :imach
+       ;; Java comes last: if someone uses C via CFFI or otherwise JNA or JNI,
+       ;; we may have to segregate the code still by architecture.
+       (:java :java :java-1.4 :java-1.5 :java-1.6 :java-1.7))))
+
+  #+clozure
+  (defun ccl-fasl-version ()
+    ;; the fasl version is target-dependent from CCL 1.8 on.
+    (or (let ((s 'ccl::target-fasl-version))
+          (and (fboundp s) (funcall s)))
+        (and (boundp 'ccl::fasl-version)
+             (symbol-value 'ccl::fasl-version))
+        (error "Can't determine fasl version.")))
+
+  (defun lisp-version-string ()
+    (let ((s (lisp-implementation-version)))
+      (car ; as opposed to OR, this idiom prevents some unreachable code warning
+       (list
+        #+allegro
+        (format nil "~A~@[~A~]~@[~A~]~@[~A~]"
+                excl::*common-lisp-version-number*
+                ;; M means "modern", as opposed to ANSI-compatible mode (which I consider default)
+                (and (eq excl:*current-case-mode* :case-sensitive-lower) "M")
+                ;; Note if not using International ACL
+                ;; see http://www.franz.com/support/documentation/8.1/doc/operators/excl/ics-target-case.htm
+                (excl:ics-target-case (:-ics "8"))
+                (and (member :smp *features*) "S"))
+        #+armedbear (format nil "~a-fasl~a" s system::*fasl-version*)
+        #+clisp
+        (subseq s 0 (position #\space s)) ; strip build information (date, etc.)
+        #+clozure
+        (format nil "~d.~d-f~d" ; shorten for windows
+                ccl::*openmcl-major-version*
+                ccl::*openmcl-minor-version*
+                (logand (ccl-fasl-version) #xFF))
+        #+cmu (substitute #\- #\/ s)
+        #+scl (format nil "~A~A" s
+                      ;; ANSI upper case vs lower case.
+                      (ecase ext:*case-mode* (:upper "") (:lower "l")))
+        #+ecl (format nil "~A~@[-~A~]" s
+                      (let ((vcs-id (ext:lisp-implementation-vcs-id)))
+                        (subseq vcs-id 0 (min (length vcs-id) 8))))
+        #+gcl (subseq s (1+ (position #\space s)))
+        #+genera
+        (multiple-value-bind (major minor) (sct:get-system-version "System")
+          (format nil "~D.~D" major minor))
+        #+mcl (subseq s 8) ; strip the leading "Version "
+        s))))
+
+  (defun implementation-identifier ()
+    (substitute-if
+     #\_ #'(lambda (x) (find x " /:;&^\\|?<>(){}[]$#`'\""))
+     (format nil "~(~a~@{~@[-~a~]~}~)"
+             (or (implementation-type) (lisp-implementation-type))
+             (or (lisp-version-string) (lisp-implementation-version))
+             (or (operating-system) (software-type))
+             (or (architecture) (machine-type))))))
 
 
 ;;;; Other system information
 
-(defun* hostname ()
-  ;; Note: untested on RMCL
-  #+(or abcl clozure cmucl ecl genera lispworks mcl mkcl sbcl scl xcl) (machine-instance)
-  #+cormanlisp "localhost" ;; is there a better way? Does it matter?
-  #+allegro (symbol-call :excl.osi :gethostname)
-  #+clisp (first (split-string (machine-instance) :separator " "))
-  #+gcl (system:gethostname))
+(with-upgradability ()
+  (defun hostname ()
+    ;; Note: untested on RMCL
+    #+(or abcl clozure cmucl ecl genera lispworks mcl mkcl sbcl scl xcl) (machine-instance)
+    #+cormanlisp "localhost" ;; is there a better way? Does it matter?
+    #+allegro (symbol-call :excl.osi :gethostname)
+    #+clisp (first (split-string (machine-instance) :separator " "))
+    #+gcl (system:gethostname)))
 
 
 ;;; Current directory
+(with-upgradability ()
 
-(defun* getcwd ()
-  "Get the current working directory as per POSIX getcwd(3), as a pathname object"
-  (or #+abcl (parse-namestring
-              (java:jstatic "getProperty" "java.lang.System" "user.dir") :ensure-directory t)
-      #+allegro (excl::current-directory)
-      #+clisp (ext:default-directory)
-      #+clozure (ccl:current-directory)
-      #+(or cmu scl) (ext:parse-unix-namestring
-                      (nth-value 1 (unix:unix-current-directory)) :ensure-directory t)
-      #+cormanlisp (pathname (pl::get-current-directory)) ;; Q: what type does it return?
-      #+ecl (ext:getcwd)
-      #+gcl (parse-namestring ;; this is a joke. Isn't there a better way?
-             (first (symbol-call :asdf/driver :run-program '("/bin/pwd") :output :lines)))
-      #+genera *default-pathname-defaults* ;; on a Lisp OS, it *is* canonical!
-      #+lispworks (system:current-directory)
-      #+mkcl (mk-ext:getcwd)
-      #+sbcl (sb-ext:parse-native-namestring (sb-unix:posix-getcwd/))
-      #+xcl (extensions:current-directory)
-      (error "getcwd not supported on your implementation")))
-
-(defun* chdir (x)
-  "Change current directory, as per POSIX chdir(2)"
-  (declare (ignorable x))
-  (or #+abcl (java:jstatic "setProperty" "java.lang.System" "user.dir" (namestring x))
-      #+allegro (excl:chdir x)
-      #+clisp (ext:cd x)
-      #+clozure (setf (ccl:current-directory) x)
-      #+(or cmu scl) (unix:unix-chdir (ext:unix-namestring x))
-      #+cormanlisp (unless (zerop (win32::_chdir (namestring x)))
-                     (error "Could not set current directory to ~A" x))
-      #+ecl (ext:chdir x)
-      #+genera (setf *default-pathname-defaults* (pathname x))
-      #+lispworks (hcl:change-directory x)
-      #+mkcl (mk-ext:chdir x)
-      #+sbcl (symbol-call :sb-posix :chdir (sb-ext:native-namestring x))
-      (error "chdir not supported on your implementation")))
+  #+cmu
+  (defun parse-unix-namestring* (unix-namestring)
+    (multiple-value-bind (host device directory name type version)
+        (lisp::parse-unix-namestring unix-namestring 0 (length unix-namestring))
+      (make-pathname :host (or host lisp::*unix-host*) :device device
+                     :directory directory :name name :type type :version version)))
+
+  (defun getcwd ()
+    "Get the current working directory as per POSIX getcwd(3), as a pathname object"
+    (or #+abcl (parse-namestring
+                (java:jstatic "getProperty" "java.lang.System" "user.dir") :ensure-directory t)
+        #+allegro (excl::current-directory)
+        #+clisp (ext:default-directory)
+        #+clozure (ccl:current-directory)
+        #+(or cmu scl) (#+cmu parse-unix-namestring* #+scl lisp::parse-unix-namestring
+                        (strcat (nth-value 1 (unix:unix-current-directory)) "/"))
+        #+cormanlisp (pathname (pl::get-current-directory)) ;; Q: what type does it return?
+        #+ecl (ext:getcwd)
+        #+gcl (parse-namestring ;; this is a joke. Isn't there a better way?
+               (first (symbol-call :asdf/driver :run-program '("/bin/pwd") :output :lines)))
+        #+genera *default-pathname-defaults* ;; on a Lisp OS, it *is* canonical!
+        #+lispworks (system:current-directory)
+        #+mkcl (mk-ext:getcwd)
+        #+sbcl (sb-ext:parse-native-namestring (sb-unix:posix-getcwd/))
+        #+xcl (extensions:current-directory)
+        (error "getcwd not supported on your implementation")))
+
+  (defun chdir (x)
+    "Change current directory, as per POSIX chdir(2), to a given pathname object"
+    (if-let (x (pathname x))
+      (or #+abcl (java:jstatic "setProperty" "java.lang.System" "user.dir" (namestring x))
+          #+allegro (excl:chdir x)
+          #+clisp (ext:cd x)
+          #+clozure (setf (ccl:current-directory) x)
+          #+(or cmu scl) (unix:unix-chdir (ext:unix-namestring x))
+          #+cormanlisp (unless (zerop (win32::_chdir (namestring x)))
+                         (error "Could not set current directory to ~A" x))
+          #+ecl (ext:chdir x)
+          #+genera (setf *default-pathname-defaults* x)
+          #+lispworks (hcl:change-directory x)
+          #+mkcl (mk-ext:chdir x)
+          #+sbcl (symbol-call :sb-posix :chdir (sb-ext:native-namestring x))
+          (error "chdir not supported on your implementation")))))
 
 
 ;;;; -----------------------------------------------------------------
@@ -1548,234 +1657,214 @@
 ;;;; Jesse Hager: The Windows Shortcut File Format.
 ;;;; http://www.wotsit.org/list.asp?fc=13
 
-#-(or clisp genera) ; CLISP doesn't need it, and READ-SEQUENCE annoys old Genera.
-(progn
-(defparameter *link-initial-dword* 76)
-(defparameter *link-guid* #(1 20 2 0 0 0 0 0 192 0 0 0 0 0 0 70))
-
-(defun* read-null-terminated-string (s)
-  (with-output-to-string (out)
-    (loop :for code = (read-byte s)
-      :until (zerop code)
-      :do (write-char (code-char code) out))))
-
-(defun* read-little-endian (s &optional (bytes 4))
-  (loop :for i :from 0 :below bytes
-    :sum (ash (read-byte s) (* 8 i))))
-
-(defun* parse-file-location-info (s)
-  (let ((start (file-position s))
-        (total-length (read-little-endian s))
-        (end-of-header (read-little-endian s))
-        (fli-flags (read-little-endian s))
-        (local-volume-offset (read-little-endian s))
-        (local-offset (read-little-endian s))
-        (network-volume-offset (read-little-endian s))
-        (remaining-offset (read-little-endian s)))
-    (declare (ignore total-length end-of-header local-volume-offset))
-    (unless (zerop fli-flags)
-      (cond
-        ((logbitp 0 fli-flags)
-          (file-position s (+ start local-offset)))
-        ((logbitp 1 fli-flags)
-          (file-position s (+ start
-                              network-volume-offset
-                              #x14))))
-      (strcat (read-null-terminated-string s)
-              (progn
-                (file-position s (+ start remaining-offset))
-                (read-null-terminated-string s))))))
-
-(defun* parse-windows-shortcut (pathname)
-  (with-open-file (s pathname :element-type '(unsigned-byte 8))
-    (handler-case
-        (when (and (= (read-little-endian s) *link-initial-dword*)
-                   (let ((header (make-array (length *link-guid*))))
-                     (read-sequence header s)
-                     (equalp header *link-guid*)))
-          (let ((flags (read-little-endian s)))
-            (file-position s 76)        ;skip rest of header
-            (when (logbitp 0 flags)
-              ;; skip shell item id list
-              (let ((length (read-little-endian s 2)))
-                (file-position s (+ length (file-position s)))))
-            (cond
-              ((logbitp 1 flags)
-                (parse-file-location-info s))
-              (t
-                (when (logbitp 2 flags)
-                  ;; skip description string
+(with-upgradability ()
+  #-(or clisp genera) ; CLISP doesn't need it, and READ-SEQUENCE annoys old Genera.
+  (progn
+    (defparameter *link-initial-dword* 76)
+    (defparameter *link-guid* #(1 20 2 0 0 0 0 0 192 0 0 0 0 0 0 70))
+
+    (defun read-null-terminated-string (s)
+      (with-output-to-string (out)
+        (loop :for code = (read-byte s)
+              :until (zerop code)
+              :do (write-char (code-char code) out))))
+
+    (defun read-little-endian (s &optional (bytes 4))
+      (loop :for i :from 0 :below bytes
+            :sum (ash (read-byte s) (* 8 i))))
+
+    (defun parse-file-location-info (s)
+      (let ((start (file-position s))
+            (total-length (read-little-endian s))
+            (end-of-header (read-little-endian s))
+            (fli-flags (read-little-endian s))
+            (local-volume-offset (read-little-endian s))
+            (local-offset (read-little-endian s))
+            (network-volume-offset (read-little-endian s))
+            (remaining-offset (read-little-endian s)))
+        (declare (ignore total-length end-of-header local-volume-offset))
+        (unless (zerop fli-flags)
+          (cond
+            ((logbitp 0 fli-flags)
+             (file-position s (+ start local-offset)))
+            ((logbitp 1 fli-flags)
+             (file-position s (+ start
+                                 network-volume-offset
+                                 #x14))))
+          (strcat (read-null-terminated-string s)
+                  (progn
+                    (file-position s (+ start remaining-offset))
+                    (read-null-terminated-string s))))))
+
+    (defun parse-windows-shortcut (pathname)
+      (with-open-file (s pathname :element-type '(unsigned-byte 8))
+        (handler-case
+            (when (and (= (read-little-endian s) *link-initial-dword*)
+                       (let ((header (make-array (length *link-guid*))))
+                         (read-sequence header s)
+                         (equalp header *link-guid*)))
+              (let ((flags (read-little-endian s)))
+                (file-position s 76)        ;skip rest of header
+                (when (logbitp 0 flags)
+                  ;; skip shell item id list
                   (let ((length (read-little-endian s 2)))
                     (file-position s (+ length (file-position s)))))
-                (when (logbitp 3 flags)
-                  ;; finally, our pathname
-                  (let* ((length (read-little-endian s 2))
-                         (buffer (make-array length)))
-                    (read-sequence buffer s)
-                    (map 'string #'code-char buffer)))))))
-      (end-of-file (c)
-        (declare (ignore c))
-        nil)))))
+                (cond
+                  ((logbitp 1 flags)
+                   (parse-file-location-info s))
+                  (t
+                   (when (logbitp 2 flags)
+                     ;; skip description string
+                     (let ((length (read-little-endian s 2)))
+                       (file-position s (+ length (file-position s)))))
+                   (when (logbitp 3 flags)
+                     ;; finally, our pathname
+                     (let* ((length (read-little-endian s 2))
+                            (buffer (make-array length)))
+                       (read-sequence buffer s)
+                       (map 'string #'code-char buffer)))))))
+          (end-of-file (c)
+            (declare (ignore c))
+            nil))))))
 
 
 ;;;; -------------------------------------------------------------------------
 ;;;; Portability layer around Common Lisp pathnames
+;; This layer allows for portable manipulation of pathname objects themselves,
+;; which all is necessary prior to any access the filesystem or environment.
 
 (asdf/package:define-package :asdf/pathname
   (:recycle :asdf/pathname :asdf)
   (:use :asdf/common-lisp :asdf/package :asdf/utility :asdf/os)
   (:export
-   #:*resolve-symlinks*
-   ;; Making pathnames, portably
+   ;; Making and merging pathnames, portably
    #:normalize-pathname-directory-component #:denormalize-pathname-directory-component
    #:merge-pathname-directory-components #:*unspecific-pathname-type* #:make-pathname*
    #:make-pathname-component-logical #:make-pathname-logical
    #:merge-pathnames*
+   #:nil-pathname #:*nil-pathname* #:with-pathname-defaults
    ;; Predicates
    #:pathname-equal #:logical-pathname-p #:physical-pathname-p
    #:absolute-pathname-p #:relative-pathname-p #:hidden-pathname-p #:file-pathname-p
    ;; Directories
    #:pathname-directory-pathname #:pathname-parent-directory-pathname
    #:directory-pathname-p #:ensure-directory-pathname
-   ;; defaults
-   #:nil-pathname #:with-pathname-defaults #:*nil-pathname*
    ;; Parsing filenames
    #:component-name-to-pathname-components
    #:split-name-type #:parse-unix-namestring #:unix-namestring
    #:split-unix-namestring-directory-components
-   #:native-namestring #:parse-native-namestring
+   ;; Absolute and relative pathnames
    #:subpathname #:subpathname*
-   ;; Wildcard pathnames
-   #:*wild* #:*wild-file* #:*wild-directory* #:*wild-inferiors* #:*wild-path* #:wilden
-   ;; probe filesystem
-   #:truename* #:safe-file-write-date #:probe-file*
-   #:directory* #:filter-logical-directory-results #:directory-files #:subdirectories
-   #:collect-sub*directories
-   ;; Absolute vs relative pathnames
-   #:ensure-pathname-absolute
+   #:ensure-absolute-pathname
    #:pathname-root #:pathname-host-pathname
    #:subpathp
-   ;; Resolving symlinks somewhat
-   #:truenamize #:resolve-symlinks #:resolve-symlinks*
    ;; Checking constraints
-   #:ensure-pathname
-   ;; merging with cwd
-   #:get-pathname-defaults #:call-with-current-directory #:with-current-directory
-   ;; Environment pathnames
-   #:inter-directory-separator #:split-native-pathnames-string
-   #:getenv-pathname #:getenv-pathnames
-   #:getenv-absolute-directory #:getenv-absolute-directories
-   #:lisp-implementation-directory #:lisp-implementation-pathname-p
+   #:ensure-pathname ;; implemented in filesystem.lisp to accommodate for existence constraints
+   ;; Wildcard pathnames
+   #:*wild* #:*wild-file* #:*wild-directory* #:*wild-inferiors* #:*wild-path* #:wilden
    ;; Translate a pathname
    #:relativize-directory-component #:relativize-pathname-directory
    #:directory-separator-for-host #:directorize-pathname-host-device
    #:translate-pathname*
    #:*output-translation-function*))
-
 (in-package :asdf/pathname)
 
-;;; User-visible parameters
-(defvar *resolve-symlinks* t
-  "Determine whether or not ASDF resolves symlinks when defining systems.
-
-Defaults to T.")
-
-
 ;;; Normalizing pathnames across implementations
 
-(defun* normalize-pathname-directory-component (directory)
-  "Given a pathname directory component, return an equivalent form that is a list"
-  #+gcl2.6 (setf directory (substitute :back :parent directory))
-  (cond
-    #-(or cmu sbcl scl) ;; these implementations already normalize directory components.
-    ((stringp directory) `(:absolute ,directory))
-    #+gcl2.6
-    ((and (consp directory) (eq :root (first directory)))
-     `(:absolute ,@(rest directory)))
-    ((or (null directory)
-         (and (consp directory) (member (first directory) '(:absolute :relative))))
-     directory)
-    #+gcl2.6
-    ((consp directory)
-     `(:relative , at directory))
-    (t
-     (error (compatfmt "~@<Unrecognized pathname directory component ~S~@:>") directory))))
-
-(defun* denormalize-pathname-directory-component (directory-component)
-  #-gcl2.6 directory-component
-  #+gcl2.6
-  (let ((d (substitute-if :parent (lambda (x) (member x '(:up :back)))
-                          directory-component)))
+(with-upgradability ()
+  (defun normalize-pathname-directory-component (directory)
+    "Given a pathname directory component, return an equivalent form that is a list"
+    #+gcl2.6 (setf directory (substitute :back :parent directory))
     (cond
-      ((and (consp d) (eq :relative (first d))) (rest d))
-      ((and (consp d) (eq :absolute (first d))) `(:root ,@(rest d)))
-      (t d))))
-
-(defun* merge-pathname-directory-components (specified defaults)
-  ;; Helper for merge-pathnames* that handles directory components.
-  (let ((directory (normalize-pathname-directory-component specified)))
-    (ecase (first directory)
-      ((nil) defaults)
-      (:absolute specified)
-      (:relative
-       (let ((defdir (normalize-pathname-directory-component defaults))
-             (reldir (cdr directory)))
-         (cond
-           ((null defdir)
-            directory)
-           ((not (eq :back (first reldir)))
-            (append defdir reldir))
-           (t
-            (loop :with defabs = (first defdir)
-              :with defrev = (reverse (rest defdir))
-              :while (and (eq :back (car reldir))
-                          (or (and (eq :absolute defabs) (null defrev))
-                              (stringp (car defrev))))
-              :do (pop reldir) (pop defrev)
-              :finally (return (cons defabs (append (reverse defrev) reldir)))))))))))
-
-;; Giving :unspecific as :type argument to make-pathname is not portable.
-;; See CLHS make-pathname and 19.2.2.2.3.
-;; This will be :unspecific if supported, or NIL if not.
-(defparameter *unspecific-pathname-type*
-  #+(or abcl allegro clozure cmu gcl genera lispworks mkcl sbcl scl xcl) :unspecific
-  #+(or clisp ecl #|These haven't been tested:|# cormanlisp mcl) nil)
-
-(defun* make-pathname* (&rest keys &key (directory nil #+gcl2.6 directoryp)
-                              host (device () #+allegro devicep) name type version defaults
-                              #+scl &allow-other-keys)
-  "Takes arguments like CL:MAKE-PATHNAME in the CLHS, and
+      #-(or cmu sbcl scl) ;; these implementations already normalize directory components.
+      ((stringp directory) `(:absolute ,directory))
+      #+gcl2.6
+      ((and (consp directory) (eq :root (first directory)))
+       `(:absolute ,@(rest directory)))
+      ((or (null directory)
+           (and (consp directory) (member (first directory) '(:absolute :relative))))
+       directory)
+      #+gcl2.6
+      ((consp directory)
+       `(:relative , at directory))
+      (t
+       (error (compatfmt "~@<Unrecognized pathname directory component ~S~@:>") directory))))
+
+  (defun denormalize-pathname-directory-component (directory-component)
+    #-gcl2.6 directory-component
+    #+gcl2.6
+    (let ((d (substitute-if :parent (lambda (x) (member x '(:up :back)))
+                            directory-component)))
+      (cond
+        ((and (consp d) (eq :relative (first d))) (rest d))
+        ((and (consp d) (eq :absolute (first d))) `(:root ,@(rest d)))
+        (t d))))
+
+  (defun merge-pathname-directory-components (specified defaults)
+    ;; Helper for merge-pathnames* that handles directory components.
+    (let ((directory (normalize-pathname-directory-component specified)))
+      (ecase (first directory)
+        ((nil) defaults)
+        (:absolute specified)
+        (:relative
+         (let ((defdir (normalize-pathname-directory-component defaults))
+               (reldir (cdr directory)))
+           (cond
+             ((null defdir)
+              directory)
+             ((not (eq :back (first reldir)))
+              (append defdir reldir))
+             (t
+              (loop :with defabs = (first defdir)
+                    :with defrev = (reverse (rest defdir))
+                    :while (and (eq :back (car reldir))
+                                (or (and (eq :absolute defabs) (null defrev))
+                                    (stringp (car defrev))))
+                    :do (pop reldir) (pop defrev)
+                    :finally (return (cons defabs (append (reverse defrev) reldir)))))))))))
+
+  ;; Giving :unspecific as :type argument to make-pathname is not portable.
+  ;; See CLHS make-pathname and 19.2.2.2.3.
+  ;; This will be :unspecific if supported, or NIL if not.
+  (defparameter *unspecific-pathname-type*
+    #+(or abcl allegro clozure cmu gcl genera lispworks mkcl sbcl scl xcl) :unspecific
+    #+(or clisp ecl #|These haven't been tested:|# cormanlisp mcl) nil)
+
+  (defun make-pathname* (&rest keys &key (directory nil #+gcl2.6 directoryp)
+                                      host (device () #+allegro devicep) name type version defaults
+                                      #+scl &allow-other-keys)
+    "Takes arguments like CL:MAKE-PATHNAME in the CLHS, and
    tries hard to make a pathname that will actually behave as documented,
    despite the peculiarities of each implementation"
-  (declare (ignorable host device directory name type version defaults))
-  (apply 'make-pathname
-         (append
-          #+allegro (when (and devicep (null device)) `(:device :unspecific))
-          #+gcl2.6
-          (when directoryp
-            `(:directory ,(denormalize-pathname-directory-component directory)))
-          keys)))
-
-(defun* make-pathname-component-logical (x)
-  "Make a pathname component suitable for use in a logical-pathname"
-  (typecase x
-    ((eql :unspecific) nil)
-    #+clisp (string (string-upcase x))
-    #+clisp (cons (mapcar 'make-pathname-component-logical x))
-    (t x)))
+    (declare (ignorable host device directory name type version defaults))
+    (apply 'make-pathname
+           (append
+            #+allegro (when (and devicep (null device)) `(:device :unspecific))
+            #+gcl2.6
+            (when directoryp
+              `(:directory ,(denormalize-pathname-directory-component directory)))
+            keys)))
+
+  (defun make-pathname-component-logical (x)
+    "Make a pathname component suitable for use in a logical-pathname"
+    (typecase x
+      ((eql :unspecific) nil)
+      #+clisp (string (string-upcase x))
+      #+clisp (cons (mapcar 'make-pathname-component-logical x))
+      (t x)))
 
-(defun* make-pathname-logical (pathname host)
-  "Take a PATHNAME's directory, name, type and version components,
+  (defun make-pathname-logical (pathname host)
+    "Take a PATHNAME's directory, name, type and version components,
 and make a new pathname with corresponding components and specified logical HOST"
-  (make-pathname*
-   :host host
-   :directory (make-pathname-component-logical (pathname-directory pathname))
-   :name (make-pathname-component-logical (pathname-name pathname))
-   :type (make-pathname-component-logical (pathname-type pathname))
-   :version (make-pathname-component-logical (pathname-version pathname))))
+    (make-pathname*
+     :host host
+     :directory (make-pathname-component-logical (pathname-directory pathname))
+     :name (make-pathname-component-logical (pathname-name pathname))
+     :type (make-pathname-component-logical (pathname-type pathname))
+     :version (make-pathname-component-logical (pathname-version pathname))))
 
-(defun* merge-pathnames* (specified &optional (defaults *default-pathname-defaults*))
-  "MERGE-PATHNAMES* is like MERGE-PATHNAMES except that
+  (defun merge-pathnames* (specified &optional (defaults *default-pathname-defaults*))
+    "MERGE-PATHNAMES* is like MERGE-PATHNAMES except that
 if the SPECIFIED pathname does not have an absolute directory,
 then the HOST and DEVICE both come from the DEFAULTS, whereas
 if the SPECIFIED pathname does have an absolute directory,
@@ -1785,95 +1874,114 @@
 Also, if either argument is NIL, then the other argument is returned unmodified;
 this is unlike MERGE-PATHNAME which always merges with a pathname,
 by default *DEFAULT-PATHNAME-DEFAULTS*, which cannot be NIL."
-  (when (null specified) (return-from merge-pathnames* defaults))
-  (when (null defaults) (return-from merge-pathnames* specified))
-  #+scl
-  (ext:resolve-pathname specified defaults)
-  #-scl
-  (let* ((specified (pathname specified))
-         (defaults (pathname defaults))
-         (directory (normalize-pathname-directory-component (pathname-directory specified)))
-         (name (or (pathname-name specified) (pathname-name defaults)))
-         (type (or (pathname-type specified) (pathname-type defaults)))
-         (version (or (pathname-version specified) (pathname-version defaults))))
-    (labels ((unspecific-handler (p)
-               (if (typep p 'logical-pathname) #'make-pathname-component-logical #'identity)))
-      (multiple-value-bind (host device directory unspecific-handler)
-          (ecase (first directory)
-            ((:absolute)
-             (values (pathname-host specified)
-                     (pathname-device specified)
-                     directory
-                     (unspecific-handler specified)))
-            ((nil :relative)
-             (values (pathname-host defaults)
-                     (pathname-device defaults)
-                     (merge-pathname-directory-components directory (pathname-directory defaults))
-                     (unspecific-handler defaults))))
-        (make-pathname* :host host :device device :directory directory
-                        :name (funcall unspecific-handler name)
-                        :type (funcall unspecific-handler type)
-                        :version (funcall unspecific-handler version))))))
+    (when (null specified) (return-from merge-pathnames* defaults))
+    (when (null defaults) (return-from merge-pathnames* specified))
+    #+scl
+    (ext:resolve-pathname specified defaults)
+    #-scl
+    (let* ((specified (pathname specified))
+           (defaults (pathname defaults))
+           (directory (normalize-pathname-directory-component (pathname-directory specified)))
+           (name (or (pathname-name specified) (pathname-name defaults)))
+           (type (or (pathname-type specified) (pathname-type defaults)))
+           (version (or (pathname-version specified) (pathname-version defaults))))
+      (labels ((unspecific-handler (p)
+                 (if (typep p 'logical-pathname) #'make-pathname-component-logical #'identity)))
+        (multiple-value-bind (host device directory unspecific-handler)
+            (ecase (first directory)
+              ((:absolute)
+               (values (pathname-host specified)
+                       (pathname-device specified)
+                       directory
+                       (unspecific-handler specified)))
+              ((nil :relative)
+               (values (pathname-host defaults)
+                       (pathname-device defaults)
+                       (merge-pathname-directory-components directory (pathname-directory defaults))
+                       (unspecific-handler defaults))))
+          (make-pathname* :host host :device device :directory directory
+                          :name (funcall unspecific-handler name)
+                          :type (funcall unspecific-handler type)
+                          :version (funcall unspecific-handler version))))))
 
+  (defun nil-pathname (&optional (defaults *default-pathname-defaults*))
+    "A pathname that is as neutral as possible for use as defaults
+   when merging, making or parsing pathnames"
+    ;; 19.2.2.2.1 says a NIL host can mean a default host;
+    ;; see also "valid physical pathname host" in the CLHS glossary, that suggests
+    ;; strings and lists of strings or :unspecific
+    ;; But CMUCL decides to die on NIL.
+    #.`(make-pathname* :directory nil :name nil :type nil :version nil :device nil
+                       :host (or #+cmu lisp::*unix-host*)
+                       #+scl ,@'(:scheme nil :scheme-specific-part nil
+                                 :username nil :password nil :parameters nil :query nil :fragment nil)
+                       ;; the default shouldn't matter, but we really want something physical
+                       :defaults defaults))
 
-;;; Some pathname predicates
+  (defvar *nil-pathname* (nil-pathname (translate-logical-pathname (user-homedir-pathname))))
 
-(defun* pathname-equal (p1 p2)
-  (when (stringp p1) (setf p1 (pathname p1)))
-  (when (stringp p2) (setf p2 (pathname p2)))
-  (flet ((normalize-component (x)
-           (unless (member x '(nil :unspecific :newest (:relative)) :test 'equal)
-             x)))
-    (macrolet ((=? (&rest accessors)
-                 (flet ((frob (x)
-                          (reduce 'list (cons 'normalize-component accessors)
-                                  :initial-value x :from-end t)))
-                   `(equal ,(frob 'p1) ,(frob 'p2)))))
-      (or (and (null p1) (null p2))
-          (and (pathnamep p1) (pathnamep p2)
-               (and (=? pathname-host)
-                    (=? pathname-device)
-                    (=? normalize-pathname-directory-component pathname-directory)
-                    (=? pathname-name)
-                    (=? pathname-type)
-                    (=? pathname-version)))))))
+  (defmacro with-pathname-defaults ((&optional defaults) &body body)
+    `(let ((*default-pathname-defaults* ,(or defaults '*nil-pathname*))) , at body)))
 
-(defun* logical-pathname-p (x)
-  (typep x 'logical-pathname))
 
-(defun* physical-pathname-p (x)
-  (and (pathnamep x) (not (logical-pathname-p x))))
+;;; Some pathname predicates
+(with-upgradability ()
+  (defun pathname-equal (p1 p2)
+    (when (stringp p1) (setf p1 (pathname p1)))
+    (when (stringp p2) (setf p2 (pathname p2)))
+    (flet ((normalize-component (x)
+             (unless (member x '(nil :unspecific :newest (:relative)) :test 'equal)
+               x)))
+      (macrolet ((=? (&rest accessors)
+                   (flet ((frob (x)
+                            (reduce 'list (cons 'normalize-component accessors)
+                                    :initial-value x :from-end t)))
+                     `(equal ,(frob 'p1) ,(frob 'p2)))))
+        (or (and (null p1) (null p2))
+            (and (pathnamep p1) (pathnamep p2)
+                 (and (=? pathname-host)
+                      (=? pathname-device)
+                      (=? normalize-pathname-directory-component pathname-directory)
+                      (=? pathname-name)
+                      (=? pathname-type)
+                      (=? pathname-version)))))))
 
-(defun* absolute-pathname-p (pathspec)
-  "If PATHSPEC is a pathname or namestring object that parses as a pathname
+  (defun logical-pathname-p (x)
+    (typep x 'logical-pathname))
+
+  (defun physical-pathname-p (x)
+    (and (pathnamep x) (not (logical-pathname-p x))))
+
+  (defun absolute-pathname-p (pathspec)
+    "If PATHSPEC is a pathname or namestring object that parses as a pathname
 possessing an :ABSOLUTE directory component, return the (parsed) pathname.
 Otherwise return NIL"
-  (and pathspec
-       (typep pathspec '(or null pathname string))
-       (let ((pathname (pathname pathspec)))
-         (and (eq :absolute (car (normalize-pathname-directory-component
-                                  (pathname-directory pathname))))
-              pathname))))
+    (and pathspec
+         (typep pathspec '(or null pathname string))
+         (let ((pathname (pathname pathspec)))
+           (and (eq :absolute (car (normalize-pathname-directory-component
+                                    (pathname-directory pathname))))
+                pathname))))
 
-(defun* relative-pathname-p (pathspec)
-  "If PATHSPEC is a pathname or namestring object that parses as a pathname
+  (defun relative-pathname-p (pathspec)
+    "If PATHSPEC is a pathname or namestring object that parses as a pathname
 possessing a :RELATIVE or NIL directory component, return the (parsed) pathname.
 Otherwise return NIL"
-  (and pathspec
-       (typep pathspec '(or null pathname string))
-       (let* ((pathname (pathname pathspec))
-              (directory (normalize-pathname-directory-component
-                          (pathname-directory pathname))))
-         (when (or (null directory) (eq :relative (car directory)))
-           pathname))))
+    (and pathspec
+         (typep pathspec '(or null pathname string))
+         (let* ((pathname (pathname pathspec))
+                (directory (normalize-pathname-directory-component
+                            (pathname-directory pathname))))
+           (when (or (null directory) (eq :relative (car directory)))
+             pathname))))
 
-(defun* hidden-pathname-p (pathname)
-  "Return a boolean that is true if the pathname is hidden as per Unix style,
+  (defun hidden-pathname-p (pathname)
+    "Return a boolean that is true if the pathname is hidden as per Unix style,
 i.e. its name starts with a dot."
-  (and pathname (equal (first-char (pathname-name pathname)) #\.)))
+    (and pathname (equal (first-char (pathname-name pathname)) #\.)))
 
-(defun* file-pathname-p (pathname)
-  "Does PATHNAME represent a file, i.e. has a non-null NAME component?
+  (defun file-pathname-p (pathname)
+    "Does PATHNAME represent a file, i.e. has a non-null NAME component?
 
 Accepts NIL, a string (converted through PARSE-NAMESTRING) or a PATHNAME.
 
@@ -1881,31 +1989,33 @@
 actually-existing file.
 
 Returns the (parsed) PATHNAME when true"
-  (when pathname
-    (let* ((pathname (pathname pathname))
-           (name (pathname-name pathname)))
-      (when (not (member name '(nil :unspecific "") :test 'equal))
-        pathname))))
+    (when pathname
+      (let* ((pathname (pathname pathname))
+             (name (pathname-name pathname)))
+        (when (not (member name '(nil :unspecific "") :test 'equal))
+          pathname)))))
 
 
 ;;; Directory pathnames
-(defun* pathname-directory-pathname (pathname)
-  "Returns a new pathname with same HOST, DEVICE, DIRECTORY as PATHNAME,
+(with-upgradability ()
+  (defun pathname-directory-pathname (pathname)
+    "Returns a new pathname with same HOST, DEVICE, DIRECTORY as PATHNAME,
 and NIL NAME, TYPE and VERSION components"
-  (when pathname
-    (make-pathname :name nil :type nil :version nil :defaults pathname)))
+    (when pathname
+      (make-pathname :name nil :type nil :version nil :defaults pathname)))
 
-(defun* pathname-parent-directory-pathname (pathname)
-  "Returns a new pathname with same HOST, DEVICE, DIRECTORY as PATHNAME,
-and NIL NAME, TYPE and VERSION components"
-  (when pathname
-    (make-pathname* :name nil :type nil :version nil
-                    :directory (merge-pathname-directory-components
-                                '(:relative :back) (pathname-directory pathname))
-                    :defaults pathname)))
+  (defun pathname-parent-directory-pathname (pathname)
+    "Returns a new pathname that corresponds to the parent of the current pathname's directory,
+i.e. removing one level of depth in the DIRECTORY component. e.g. if pathname is
+Unix pathname /foo/bar/baz/file.type then return /foo/bar/"
+    (when pathname
+      (make-pathname* :name nil :type nil :version nil
+                      :directory (merge-pathname-directory-components
+                                  '(:relative :back) (pathname-directory pathname))
+                      :defaults pathname)))
 
-(defun* directory-pathname-p (pathname)
-  "Does PATHNAME represent a directory?
+  (defun directory-pathname-p (pathname)
+    "Does PATHNAME represent a directory?
 
 A directory-pathname is a pathname _without_ a filename. The three
 ways that the filename components can be missing are for it to be NIL,
@@ -1913,57 +2023,39 @@
 
 Note that this does _not_ check to see that PATHNAME points to an
 actually-existing directory."
-  (when pathname
-    (let ((pathname (pathname pathname)))
-      (flet ((check-one (x)
-               (member x '(nil :unspecific "") :test 'equal)))
-        (and (not (wild-pathname-p pathname))
-             (check-one (pathname-name pathname))
-             (check-one (pathname-type pathname))
-             t)))))
+    (when pathname
+      (let ((pathname (pathname pathname)))
+        (flet ((check-one (x)
+                 (member x '(nil :unspecific "") :test 'equal)))
+          (and (not (wild-pathname-p pathname))
+               (check-one (pathname-name pathname))
+               (check-one (pathname-type pathname))
+               t)))))
 
-(defun* ensure-directory-pathname (pathspec &optional (on-error 'error))
-  "Converts the non-wild pathname designator PATHSPEC to directory form."
-  (cond
-   ((stringp pathspec)
-    (ensure-directory-pathname (pathname pathspec)))
-   ((not (pathnamep pathspec))
-    (call-function on-error (compatfmt "~@<Invalid pathname designator ~S~@:>") pathspec))
-   ((wild-pathname-p pathspec)
-    (call-function on-error (compatfmt "~@<Can't reliably convert wild pathname ~3i~_~S~@:>") pathspec))
-   ((directory-pathname-p pathspec)
-    pathspec)
-   (t
-    (make-pathname* :directory (append (or (normalize-pathname-directory-component
-                                            (pathname-directory pathspec))
-                                           (list :relative))
-                                       (list (file-namestring pathspec)))
-                    :name nil :type nil :version nil :defaults pathspec))))
-
-
-;;; defaults
-(defun* nil-pathname (&optional (defaults *default-pathname-defaults*))
-  "A pathname that is as neutral as possible for use as defaults
-   when merging, making or parsing pathnames"
-  ;; 19.2.2.2.1 says a NIL host can mean a default host;
-  ;; see also "valid physical pathname host" in the CLHS glossary, that suggests
-  ;; strings and lists of strings or :unspecific
-  ;; But CMUCL decides to die on NIL.
-  (make-pathname* :directory nil :name nil :type nil :version nil :device nil
-                  :host (or #+cmu lisp::*unix-host*)
-                  ;; the default shouldn't matter, but we really want something physical
-                  :defaults defaults))
-
-(defvar *nil-pathname* (nil-pathname (translate-logical-pathname (user-homedir-pathname))))
-
-(defmacro with-pathname-defaults ((&optional defaults) &body body)
-  `(let ((*default-pathname-defaults* ,(or defaults '*nil-pathname*))) , at body))
-
-
-;;; Parsing filenames and lists thereof
-(defun* split-unix-namestring-directory-components
-    (unix-namestring &key ensure-directory dot-dot)
-  "Splits the path string UNIX-NAMESTRING, returning four values:
+  (defun ensure-directory-pathname (pathspec &optional (on-error 'error))
+    "Converts the non-wild pathname designator PATHSPEC to directory form."
+    (cond
+      ((stringp pathspec)
+       (ensure-directory-pathname (pathname pathspec)))
+      ((not (pathnamep pathspec))
+       (call-function on-error (compatfmt "~@<Invalid pathname designator ~S~@:>") pathspec))
+      ((wild-pathname-p pathspec)
+       (call-function on-error (compatfmt "~@<Can't reliably convert wild pathname ~3i~_~S~@:>") pathspec))
+      ((directory-pathname-p pathspec)
+       pathspec)
+      (t
+       (make-pathname* :directory (append (or (normalize-pathname-directory-component
+                                               (pathname-directory pathspec))
+                                              (list :relative))
+                                          (list (file-namestring pathspec)))
+                       :name nil :type nil :version nil :defaults pathspec)))))
+
+
+;;; Parsing filenames
+(with-upgradability ()
+  (defun split-unix-namestring-directory-components
+      (unix-namestring &key ensure-directory dot-dot)
+    "Splits the path string UNIX-NAMESTRING, returning four values:
 A flag that is either :absolute or :relative, indicating
    how the rest of the values are to be interpreted.
 A directory path --- a list of strings and keywords, suitable for
@@ -1985,49 +2077,49 @@
 
 The intention of this function is to support structured component names,
 e.g., \(:file \"foo/bar\"\), which will be unpacked to relative pathnames."
-  (check-type unix-namestring string)
-  (check-type dot-dot (member nil :back :up))
-  (if (and (not (find #\/ unix-namestring)) (not ensure-directory)
-           (plusp (length unix-namestring)))
-      (values :relative () unix-namestring t)
-      (let* ((components (split-string unix-namestring :separator "/"))
-             (last-comp (car (last components))))
-        (multiple-value-bind (relative components)
-            (if (equal (first components) "")
-                (if (equal (first-char unix-namestring) #\/)
-                    (values :absolute (cdr components))
-                    (values :relative nil))
-                (values :relative components))
-          (setf components (remove-if #'(lambda (x) (member x '("" ".") :test #'equal))
-                                      components))
-          (setf components (substitute (or dot-dot :back) ".." components :test #'equal))
-          (cond
-            ((equal last-comp "")
-             (values relative components nil nil)) ; "" already removed from components
-            (ensure-directory
-             (values relative components nil nil))
-            (t
-             (values relative (butlast components) last-comp nil)))))))
+    (check-type unix-namestring string)
+    (check-type dot-dot (member nil :back :up))
+    (if (and (not (find #\/ unix-namestring)) (not ensure-directory)
+             (plusp (length unix-namestring)))
+        (values :relative () unix-namestring t)
+        (let* ((components (split-string unix-namestring :separator "/"))
+               (last-comp (car (last components))))
+          (multiple-value-bind (relative components)
+              (if (equal (first components) "")
+                  (if (equal (first-char unix-namestring) #\/)
+                      (values :absolute (cdr components))
+                      (values :relative nil))
+                  (values :relative components))
+            (setf components (remove-if #'(lambda (x) (member x '("" ".") :test #'equal))
+                                        components))
+            (setf components (substitute (or dot-dot :back) ".." components :test #'equal))
+            (cond
+              ((equal last-comp "")
+               (values relative components nil nil)) ; "" already removed from components
+              (ensure-directory
+               (values relative components nil nil))
+              (t
+               (values relative (butlast components) last-comp nil)))))))
 
-(defun* split-name-type (filename)
-  "Split a filename into two values NAME and TYPE that are returned.
+  (defun split-name-type (filename)
+    "Split a filename into two values NAME and TYPE that are returned.
 We assume filename has no directory component.
 The last . if any separates name and type from from type,
 except that if there is only one . and it is in first position,
 the whole filename is the NAME with an empty type.
 NAME is always a string.
 For an empty type, *UNSPECIFIC-PATHNAME-TYPE* is returned."
-  (check-type filename string)
-  (assert (plusp (length filename)))
-  (destructuring-bind (name &optional (type *unspecific-pathname-type*))
-      (split-string filename :max 2 :separator ".")
-    (if (equal name "")
-        (values filename *unspecific-pathname-type*)
-        (values name type))))
-
-(defun* parse-unix-namestring (name &rest keys &key type defaults dot-dot ensure-directory
-                                    &allow-other-keys)
-  "Coerce NAME into a PATHNAME using standard Unix syntax.
+    (check-type filename string)
+    (assert (plusp (length filename)))
+    (destructuring-bind (name &optional (type *unspecific-pathname-type*))
+        (split-string filename :max 2 :separator ".")
+      (if (equal name "")
+          (values filename *unspecific-pathname-type*)
+          (values name type))))
+
+  (defun parse-unix-namestring (name &rest keys &key type defaults dot-dot ensure-directory
+                                &allow-other-keys)
+    "Coerce NAME into a PATHNAME using standard Unix syntax.
 
 Unix syntax is used whether or not the underlying system is Unix;
 on such non-Unix systems it is only usable but for relative pathnames;
@@ -2068,35 +2160,35 @@
 When you're manipulating pathnames that are supposed to make sense portably
 even though the OS may not be Unixish, we recommend you use :WANT-RELATIVE T
 to throw an error if the pathname is absolute"
-  (block nil
-    (check-type type (or null string (eql :directory)))
-    (when ensure-directory
-      (setf type :directory))
-    (etypecase name
-      ((or null pathname) (return name))
-      (symbol
-       (setf name (string-downcase name)))
-      (string))
-    (multiple-value-bind (relative path filename file-only)
-        (split-unix-namestring-directory-components
-         name :dot-dot dot-dot :ensure-directory (eq type :directory))
-      (multiple-value-bind (name type)
-          (cond
-            ((or (eq type :directory) (null filename))
-             (values nil nil))
-            (type
-             (values filename type))
-            (t
-             (split-name-type filename)))
-        (apply 'ensure-pathname
-               (make-pathname*
-                :directory (unless file-only (cons relative path))
-                :name name :type type
-                :defaults (or defaults *nil-pathname*))
-               (remove-plist-keys '(:type :dot-dot :defaults) keys))))))
+    (block nil
+      (check-type type (or null string (eql :directory)))
+      (when ensure-directory
+        (setf type :directory))
+      (etypecase name
+        ((or null pathname) (return name))
+        (symbol
+         (setf name (string-downcase name)))
+        (string))
+      (multiple-value-bind (relative path filename file-only)
+          (split-unix-namestring-directory-components
+           name :dot-dot dot-dot :ensure-directory (eq type :directory))
+        (multiple-value-bind (name type)
+            (cond
+              ((or (eq type :directory) (null filename))
+               (values nil nil))
+              (type
+               (values filename type))
+              (t
+               (split-name-type filename)))
+          (apply 'ensure-pathname
+                 (make-pathname*
+                  :directory (unless file-only (cons relative path))
+                  :name name :type type
+                  :defaults (or defaults *nil-pathname*))
+                 (remove-plist-keys '(:type :dot-dot :defaults) keys))))))
 
-(defun* unix-namestring (pathname)
-  "Given a non-wild PATHNAME, return a Unix-style namestring for it.
+  (defun unix-namestring (pathname)
+    "Given a non-wild PATHNAME, return a Unix-style namestring for it.
 If the PATHNAME is NIL or a STRING, return it unchanged.
 
 This only considers the DIRECTORY, NAME and TYPE components of the pathname.
@@ -2106,357 +2198,483 @@
 
 An error is signaled if the argument is not NULL, a STRING or a PATHNAME,
 or if it is a PATHNAME but some of its components are not recognized."
-  (etypecase pathname
-    ((or null string) pathname)
-    (pathname
-     (with-output-to-string (s)
-       (flet ((err () (error "Not a valid unix-namestring ~S" pathname)))
-         (let* ((dir (normalize-pathname-directory-component (pathname-directory pathname)))
-                (name (pathname-name pathname))
-                (type (pathname-type pathname))
-                (type (and (not (eq type :unspecific)) type)))
-           (cond
-             ((eq dir ()))
-             ((eq dir '(:relative)) (princ "./" s))
-             ((consp dir)
-              (destructuring-bind (relabs &rest dirs) dir
-                (or (member relabs '(:relative :absolute)) (err))
-                (when (eq relabs :absolute) (princ #\/ s))
-                (loop :for x :in dirs :do
-                  (cond
-                    ((member x '(:back :up)) (princ "../" s))
-                    ((equal x "") (err))
-                    ;;((member x '("." "..") :test 'equal) (err))
-                    ((stringp x) (format s "~A/" x))
-                    (t (err))))))
-             (t (err)))
-           (cond
-             (name
-              (or (and (stringp name) (or (null type) (stringp type))) (err))
-              (format s "~A~@[.~A~]" name type))
-             (t
-              (or (null type) (err))))))))))
-
-(defun* native-namestring (x)
-  "From a non-wildcard CL pathname, a return namestring suitable for passing to the operating system"
-  (when x
-    (let ((p (pathname x)))
-      #+clozure (with-pathname-defaults () (ccl:native-translated-namestring p)) ; see ccl bug 978
-      #+(or cmu scl) (ext:unix-namestring p nil)
-      #+sbcl (sb-ext:native-namestring p)
-      #-(or clozure cmu sbcl scl)
-      (if (os-unix-p) (unix-namestring p)
-          (namestring p)))))
-
-(defun* parse-native-namestring (string &rest constraints &key ensure-directory &allow-other-keys)
-  "From a native namestring suitable for use by the operating system, return
-a CL pathname satisfying all the specified constraints as per ENSURE-PATHNAME"
-  (check-type string (or string null))
-  (let* ((pathname
-           (when string
-             (with-pathname-defaults ()
-               #+clozure (ccl:native-to-pathname string)
-               #+sbcl (sb-ext:parse-native-namestring string)
-               #-(or clozure sbcl)
-               (if (os-unix-p)
-                   (parse-unix-namestring string :ensure-directory ensure-directory)
-                   (parse-namestring string)))))
-         (pathname
-           (if ensure-directory
-               (and pathname (ensure-directory-pathname pathname))
-               pathname)))
-    (apply 'ensure-pathname pathname constraints)))
-
-(defun* subpathname (pathname subpath &key type)
-  "This function takes a PATHNAME and a SUBPATH and a TYPE.
+    (etypecase pathname
+      ((or null string) pathname)
+      (pathname
+       (with-output-to-string (s)
+         (flet ((err () (error "Not a valid unix-namestring ~S" pathname)))
+           (let* ((dir (normalize-pathname-directory-component (pathname-directory pathname)))
+                  (name (pathname-name pathname))
+                  (type (pathname-type pathname))
+                  (type (and (not (eq type :unspecific)) type)))
+             (cond
+               ((eq dir ()))
+               ((eq dir '(:relative)) (princ "./" s))
+               ((consp dir)
+                (destructuring-bind (relabs &rest dirs) dir
+                  (or (member relabs '(:relative :absolute)) (err))
+                  (when (eq relabs :absolute) (princ #\/ s))
+                  (loop :for x :in dirs :do
+                    (cond
+                      ((member x '(:back :up)) (princ "../" s))
+                      ((equal x "") (err))
+                      ;;((member x '("." "..") :test 'equal) (err))
+                      ((stringp x) (format s "~A/" x))
+                      (t (err))))))
+               (t (err)))
+             (cond
+               (name
+                (or (and (stringp name) (or (null type) (stringp type))) (err))
+                (format s "~A~@[.~A~]" name type))
+               (t
+                (or (null type) (err)))))))))))
+
+;;; Absolute and relative pathnames
+(with-upgradability ()
+  (defun subpathname (pathname subpath &key type)
+    "This function takes a PATHNAME and a SUBPATH and a TYPE.
 If SUBPATH is already a PATHNAME object (not namestring),
 and is an absolute pathname at that, it is returned unchanged;
 otherwise, SUBPATH is turned into a relative pathname with given TYPE
 as per PARSE-UNIX-NAMESTRING with :WANT-RELATIVE T :TYPE TYPE,
 then it is merged with the PATHNAME-DIRECTORY-PATHNAME of PATHNAME."
-  (or (and (pathnamep subpath) (absolute-pathname-p subpath))
-      (merge-pathnames* (parse-unix-namestring subpath :type type :want-relative t)
-                        (pathname-directory-pathname pathname))))
-
-(defun* subpathname* (pathname subpath &key type)
-  "returns NIL if the base pathname is NIL, otherwise like SUBPATHNAME."
-  (and pathname
-       (subpathname (ensure-directory-pathname pathname) subpath :type type)))
+    (or (and (pathnamep subpath) (absolute-pathname-p subpath))
+        (merge-pathnames* (parse-unix-namestring subpath :type type :want-relative t)
+                          (pathname-directory-pathname pathname))))
+
+  (defun subpathname* (pathname subpath &key type)
+    "returns NIL if the base pathname is NIL, otherwise like SUBPATHNAME."
+    (and pathname
+         (subpathname (ensure-directory-pathname pathname) subpath :type type)))
+
+  (defun pathname-root (pathname)
+    (make-pathname* :directory '(:absolute)
+                    :name nil :type nil :version nil
+                    :defaults pathname ;; host device, and on scl, *some*
+                    ;; scheme-specific parts: port username password, not others:
+                    . #.(or #+scl '(:parameters nil :query nil :fragment nil))))
+
+  (defun pathname-host-pathname (pathname)
+    (make-pathname* :directory nil
+                    :name nil :type nil :version nil :device nil
+                    :defaults pathname ;; host device, and on scl, *some*
+                    ;; scheme-specific parts: port username password, not others:
+                    . #.(or #+scl '(:parameters nil :query nil :fragment nil))))
+
+  (defun subpathp (maybe-subpath base-pathname)
+    (and (pathnamep maybe-subpath) (pathnamep base-pathname)
+         (absolute-pathname-p maybe-subpath) (absolute-pathname-p base-pathname)
+         (directory-pathname-p base-pathname) (not (wild-pathname-p base-pathname))
+         (pathname-equal (pathname-root maybe-subpath) (pathname-root base-pathname))
+         (with-pathname-defaults ()
+           (let ((enough (enough-namestring maybe-subpath base-pathname)))
+             (and (relative-pathname-p enough) (pathname enough))))))
+
+  (defun ensure-absolute-pathname (path &optional defaults (on-error 'error))
+    (cond
+      ((absolute-pathname-p path))
+      ((stringp path) (ensure-absolute-pathname (pathname path) defaults on-error))
+      ((not (pathnamep path)) (call-function on-error "not a valid pathname designator ~S" path))
+      ((let ((default-pathname (if (pathnamep defaults) defaults (call-function defaults))))
+         (or (if (absolute-pathname-p default-pathname)
+                 (absolute-pathname-p (merge-pathnames* path default-pathname))
+                 (call-function on-error "Default pathname ~S is not an absolute pathname"
+                                default-pathname))
+             (call-function on-error "Failed to merge ~S with ~S into an absolute pathname"
+                            path default-pathname))))
+      (t (call-function on-error
+                        "Cannot ensure ~S is evaluated as an absolute pathname with defaults ~S"
+                        path defaults)))))
 
 
 ;;; Wildcard pathnames
-(defparameter *wild* (or #+cormanlisp "*" :wild))
-(defparameter *wild-directory-component* (or #+gcl2.6 "*" :wild))
-(defparameter *wild-inferiors-component* (or #+gcl2.6 "**" :wild-inferiors))
-(defparameter *wild-file*
-  (make-pathname :directory nil :name *wild* :type *wild*
-                 :version (or #-(or allegro abcl xcl) *wild*)))
-(defparameter *wild-directory*
-  (make-pathname* :directory `(:relative ,*wild-directory-component*)
-                  :name nil :type nil :version nil))
-(defparameter *wild-inferiors*
-  (make-pathname* :directory `(:relative ,*wild-inferiors-component*)
-                  :name nil :type nil :version nil))
-(defparameter *wild-path*
-  (merge-pathnames* *wild-file* *wild-inferiors*))
+(with-upgradability ()
+  (defparameter *wild* (or #+cormanlisp "*" :wild))
+  (defparameter *wild-directory-component* (or #+gcl2.6 "*" :wild))
+  (defparameter *wild-inferiors-component* (or #+gcl2.6 "**" :wild-inferiors))
+  (defparameter *wild-file*
+    (make-pathname :directory nil :name *wild* :type *wild*
+                   :version (or #-(or allegro abcl xcl) *wild*)))
+  (defparameter *wild-directory*
+    (make-pathname* :directory `(:relative ,*wild-directory-component*)
+                    :name nil :type nil :version nil))
+  (defparameter *wild-inferiors*
+    (make-pathname* :directory `(:relative ,*wild-inferiors-component*)
+                    :name nil :type nil :version nil))
+  (defparameter *wild-path*
+    (merge-pathnames* *wild-file* *wild-inferiors*))
+
+  (defun wilden (path)
+    (merge-pathnames* *wild-path* path)))
+
+
+;;; Translate a pathname
+(with-upgradability ()
+  (defun relativize-directory-component (directory-component)
+    (let ((directory (normalize-pathname-directory-component directory-component)))
+      (cond
+        ((stringp directory)
+         (list :relative directory))
+        ((eq (car directory) :absolute)
+         (cons :relative (cdr directory)))
+        (t
+         directory))))
+
+  (defun relativize-pathname-directory (pathspec)
+    (let ((p (pathname pathspec)))
+      (make-pathname*
+       :directory (relativize-directory-component (pathname-directory p))
+       :defaults p)))
+
+  (defun directory-separator-for-host (&optional (pathname *default-pathname-defaults*))
+    (let ((foo (make-pathname* :directory '(:absolute "FOO") :defaults pathname)))
+      (last-char (namestring foo))))
+
+  #-scl
+  (defun directorize-pathname-host-device (pathname)
+    #+(or unix abcl)
+    (when (and #+abcl (os-unix-p) (physical-pathname-p pathname))
+      (return-from directorize-pathname-host-device pathname))
+    (let* ((root (pathname-root pathname))
+           (wild-root (wilden root))
+           (absolute-pathname (merge-pathnames* pathname root))
+           (separator (directory-separator-for-host root))
+           (root-namestring (namestring root))
+           (root-string
+             (substitute-if #\/
+                            #'(lambda (x) (or (eql x #\:)
+                                              (eql x separator)))
+                            root-namestring)))
+      (multiple-value-bind (relative path filename)
+          (split-unix-namestring-directory-components root-string :ensure-directory t)
+        (declare (ignore relative filename))
+        (let ((new-base
+                (make-pathname* :defaults root :directory `(:absolute , at path))))
+          (translate-pathname absolute-pathname wild-root (wilden new-base))))))
+
+  #+scl
+  (defun directorize-pathname-host-device (pathname)
+    (let ((scheme (ext:pathname-scheme pathname))
+          (host (pathname-host pathname))
+          (port (ext:pathname-port pathname))
+          (directory (pathname-directory pathname)))
+      (flet ((specificp (x) (and x (not (eq x :unspecific)))))
+        (if (or (specificp port)
+                (and (specificp host) (plusp (length host)))
+                (specificp scheme))
+            (let ((prefix ""))
+              (when (specificp port)
+                (setf prefix (format nil ":~D" port)))
+              (when (and (specificp host) (plusp (length host)))
+                (setf prefix (strcat host prefix)))
+              (setf prefix (strcat ":" prefix))
+              (when (specificp scheme)
+                (setf prefix (strcat scheme prefix)))
+              (assert (and directory (eq (first directory) :absolute)))
+              (make-pathname* :directory `(:absolute ,prefix ,@(rest directory))
+                              :defaults pathname)))
+        pathname)))
+
+  (defun* (translate-pathname*) (path absolute-source destination &optional root source)
+    (declare (ignore source))
+    (cond
+      ((functionp destination)
+       (funcall destination path absolute-source))
+      ((eq destination t)
+       path)
+      ((not (pathnamep destination))
+       (error "Invalid destination"))
+      ((not (absolute-pathname-p destination))
+       (translate-pathname path absolute-source (merge-pathnames* destination root)))
+      (root
+       (translate-pathname (directorize-pathname-host-device path) absolute-source destination))
+      (t
+       (translate-pathname path absolute-source destination))))
 
-(defun* wilden (path)
-  (merge-pathnames* *wild-path* path))
+  (defvar *output-translation-function* 'identity)) ; Hook for output translations
+
+
+;;;; -------------------------------------------------------------------------
+;;;; Portability layer around Common Lisp filesystem access
+
+(asdf/package:define-package :asdf/filesystem
+  (:recycle :asdf/pathname :asdf)
+  (:use :asdf/common-lisp :asdf/package :asdf/utility :asdf/os :asdf/pathname)
+  (:export
+   ;; Native namestrings
+   #:native-namestring #:parse-native-namestring
+   ;; Probing the filesystem
+   #:truename* #:safe-file-write-date #:probe-file*
+   #:directory* #:filter-logical-directory-results #:directory-files #:subdirectories
+   #:collect-sub*directories
+   ;; Resolving symlinks somewhat
+   #:truenamize #:resolve-symlinks #:*resolve-symlinks* #:resolve-symlinks*
+   ;; merging with cwd
+   #:get-pathname-defaults #:call-with-current-directory #:with-current-directory
+   ;; Environment pathnames
+   #:inter-directory-separator #:split-native-pathnames-string
+   #:getenv-pathname #:getenv-pathnames
+   #:getenv-absolute-directory #:getenv-absolute-directories
+   #:lisp-implementation-directory #:lisp-implementation-pathname-p
+   ;; Simple filesystem operations
+   #:ensure-all-directories-exist
+   #:rename-file-overwriting-target
+   #:delete-file-if-exists))
+(in-package :asdf/filesystem)
+
+;;; Native namestrings, as seen by the operating system calls rather than Lisp
+(with-upgradability ()
+  (defun native-namestring (x)
+    "From a non-wildcard CL pathname, a return namestring suitable for passing to the operating system"
+    (when x
+      (let ((p (pathname x)))
+        #+clozure (with-pathname-defaults () (ccl:native-translated-namestring p)) ; see ccl bug 978
+        #+(or cmu scl) (ext:unix-namestring p nil)
+        #+sbcl (sb-ext:native-namestring p)
+        #-(or clozure cmu sbcl scl)
+        (if (os-unix-p) (unix-namestring p)
+            (namestring p)))))
+
+  (defun parse-native-namestring (string &rest constraints &key ensure-directory &allow-other-keys)
+    "From a native namestring suitable for use by the operating system, return
+a CL pathname satisfying all the specified constraints as per ENSURE-PATHNAME"
+    (check-type string (or string null))
+    (let* ((pathname
+             (when string
+               (with-pathname-defaults ()
+                 #+clozure (ccl:native-to-pathname string)
+                 #+sbcl (sb-ext:parse-native-namestring string)
+                 #-(or clozure sbcl)
+                 (if (os-unix-p)
+                     (parse-unix-namestring string :ensure-directory ensure-directory)
+                     (parse-namestring string)))))
+           (pathname
+             (if ensure-directory
+                 (and pathname (ensure-directory-pathname pathname))
+                 pathname)))
+      (apply 'ensure-pathname pathname constraints))))
 
 
 ;;; Probing the filesystem
-(defun* truename* (p)
-  ;; avoids both logical-pathname merging and physical resolution issues
-  (and p (handler-case (with-pathname-defaults () (truename p)) (file-error () nil))))
-
-(defun* safe-file-write-date (pathname)
-  ;; If FILE-WRITE-DATE returns NIL, it's possible that
-  ;; the user or some other agent has deleted an input file.
-  ;; Also, generated files will not exist at the time planning is done
-  ;; and calls compute-action-stamp which calls safe-file-write-date.
-  ;; So it is very possible that we can't get a valid file-write-date,
-  ;; and we can survive and we will continue the planning
-  ;; as if the file were very old.
-  ;; (or should we treat the case in a different, special way?)
-  (handler-case (file-write-date pathname) (file-error () nil)))
+(with-upgradability ()
+  (defun truename* (p)
+    ;; avoids both logical-pathname merging and physical resolution issues
+    (and p (handler-case (with-pathname-defaults () (truename p)) (file-error () nil))))
+
+  (defun safe-file-write-date (pathname)
+    ;; If FILE-WRITE-DATE returns NIL, it's possible that
+    ;; the user or some other agent has deleted an input file.
+    ;; Also, generated files will not exist at the time planning is done
+    ;; and calls compute-action-stamp which calls safe-file-write-date.
+    ;; So it is very possible that we can't get a valid file-write-date,
+    ;; and we can survive and we will continue the planning
+    ;; as if the file were very old.
+    ;; (or should we treat the case in a different, special way?)
+    (and pathname
+         (handler-case (file-write-date (translate-logical-pathname pathname))
+           (file-error () nil))))
 
-(defun* probe-file* (p &key truename)
-  "when given a pathname P (designated by a string as per PARSE-NAMESTRING),
+  (defun probe-file* (p &key truename)
+    "when given a pathname P (designated by a string as per PARSE-NAMESTRING),
 probes the filesystem for a file or directory with given pathname.
 If it exists, return its truename is ENSURE-PATHNAME is true,
 or the original (parsed) pathname if it is false (the default)."
-  (with-pathname-defaults () ;; avoids logical-pathname issues on some implementations
-    (etypecase p
-      (null nil)
-      (string (probe-file* (parse-namestring p) :truename truename))
-      (pathname
-       (handler-case
-           (or
-            #+allegro
-            (probe-file p :follow-symlinks truename)
-            #-(or allegro clisp gcl2.6)
-            (if truename
-                (probe-file p)
-                (and (ignore-errors
-                      #+(or cmu scl) (unix:unix-stat (ext:unix-namestring (translate-logical-pathname p)))
-                      #+(and lispworks unix) (system:get-file-stat p)
-                      #+sbcl (sb-unix:unix-stat (sb-ext:native-namestring (translate-logical-pathname p)))
-                      #-(or cmu (and lispworks unix) sbcl scl)
-                      (file-write-date p))
-                     p))
-            #+(or clisp gcl2.6)
-            #.(flet ((probe (probe)
-                       `(let ((foundtrue ,probe))
-                          (cond
-                            (truename foundtrue)
-                            (foundtrue p)))))
-                #+gcl2.6
-                (probe '(or (probe-file p)
-                         (and (directory-pathname-p p)
-                          (ignore-errors
-                           (ensure-directory-pathname
-                            (truename* (subpathname
-                                        (ensure-directory-pathname p) ".")))))))
-                #+clisp
-                (let ((fs (find-symbol* '#:file-stat :posix nil))
-                      (pp (find-symbol* '#:probe-pathname :ext nil))
-                      (resolve (if pp
-                                   `(ignore-errors (,pp p))
-                                   '(or (truename* p)
-                                     (truename* (ensure-directory-pathname p))))))
-                  (if fs
-                      `(if truename
-                           ,resolve
-                           (and (,fs p) p))
-                      (probe resolve)))))
-         (file-error () nil))))))
-
-(defun* directory* (pathname-spec &rest keys &key &allow-other-keys)
-  (apply 'directory pathname-spec
-         (append keys '#.(or #+allegro '(:directories-are-files nil :follow-symbolic-links nil)
-                             #+clozure '(:follow-links nil)
-                             #+clisp '(:circle t :if-does-not-exist :ignore)
-                             #+(or cmu scl) '(:follow-links nil :truenamep nil)
-                             #+sbcl (when (find-symbol* :resolve-symlinks '#:sb-impl nil)
-                                      '(:resolve-symlinks nil))))))
-
-(defun* filter-logical-directory-results (directory entries merger)
-  (if (logical-pathname-p directory)
-      ;; Try hard to not resolve logical-pathname into physical pathnames;
-      ;; otherwise logical-pathname users/lovers will be disappointed.
-      ;; If directory* could use some implementation-dependent magic,
-      ;; we will have logical pathnames already; otherwise,
-      ;; we only keep pathnames for which specifying the name and
-      ;; translating the LPN commute.
-      (loop :for f :in entries
-        :for p = (or (and (logical-pathname-p f) f)
-                     (let* ((u (ignore-errors (funcall merger f))))
-                       ;; The first u avoids a cumbersome (truename u) error.
-                       ;; At this point f should already be a truename,
-                       ;; but isn't quite in CLISP, for it doesn't have :version :newest
-                       (and u (equal (truename* u) (truename* f)) u)))
-        :when p :collect p)
-      entries))
-
-(defun* directory-files (directory &optional (pattern *wild-file*))
-  (let ((dir (pathname directory)))
-    (when (logical-pathname-p dir)
-      ;; Because of the filtering we do below,
-      ;; logical pathnames have restrictions on wild patterns.
-      ;; Not that the results are very portable when you use these patterns on physical pathnames.
-      (when (wild-pathname-p dir)
-        (error "Invalid wild pattern in logical directory ~S" directory))
-      (unless (member (pathname-directory pattern) '(() (:relative)) :test 'equal)
-        (error "Invalid file pattern ~S for logical directory ~S" pattern directory))
-      (setf pattern (make-pathname-logical pattern (pathname-host dir))))
-    (let ((entries (ignore-errors (directory* (merge-pathnames* pattern dir)))))
+    (with-pathname-defaults () ;; avoids logical-pathname issues on some implementations
+      (etypecase p
+        (null nil)
+        (string (probe-file* (parse-namestring p) :truename truename))
+        (pathname
+         (handler-case
+             (or
+              #+allegro
+              (probe-file p :follow-symlinks truename)
+              #-(or allegro clisp gcl2.6)
+              (if truename
+                  (probe-file p)
+                  (and (not (wild-pathname-p p))
+                       (ignore-errors
+                        (let ((pp (translate-logical-pathname p)))
+                          #+(or cmu scl) (unix:unix-stat (ext:unix-namestring pp))
+                          #+(and lispworks unix) (system:get-file-stat pp)
+                          #+sbcl (sb-unix:unix-stat (sb-ext:native-namestring pp))
+                          #-(or cmu (and lispworks unix) sbcl scl) (file-write-date pp)))
+                       p))
+              #+(or clisp gcl2.6)
+              #.(flet ((probe (probe)
+                         `(let ((foundtrue ,probe))
+                            (cond
+                              (truename foundtrue)
+                              (foundtrue p)))))
+                  #+gcl2.6
+                  (probe '(or (probe-file p)
+                           (and (directory-pathname-p p)
+                            (ignore-errors
+                             (ensure-directory-pathname
+                              (truename* (subpathname
+                                          (ensure-directory-pathname p) ".")))))))
+                  #+clisp
+                  (let* ((fs (find-symbol* '#:file-stat :posix nil))
+                         (pp (find-symbol* '#:probe-pathname :ext nil))
+                         (resolve (if pp
+                                      `(ignore-errors (,pp p))
+                                      '(or (truename* p)
+                                        (truename* (ignore-errors (ensure-directory-pathname p)))))))
+                    (if fs
+                        `(if truename
+                             ,resolve
+                             (and (ignore-errors (,fs p)) p))
+                        (probe resolve)))))
+           (file-error () nil))))))
+
+  (defun directory* (pathname-spec &rest keys &key &allow-other-keys)
+    (apply 'directory pathname-spec
+           (append keys '#.(or #+allegro '(:directories-are-files nil :follow-symbolic-links nil)
+                               #+clozure '(:follow-links nil)
+                               #+clisp '(:circle t :if-does-not-exist :ignore)
+                               #+(or cmu scl) '(:follow-links nil :truenamep nil)
+                               #+sbcl (when (find-symbol* :resolve-symlinks '#:sb-impl nil)
+                                        '(:resolve-symlinks nil))))))
+
+  (defun filter-logical-directory-results (directory entries merger)
+    (if (logical-pathname-p directory)
+        ;; Try hard to not resolve logical-pathname into physical pathnames;
+        ;; otherwise logical-pathname users/lovers will be disappointed.
+        ;; If directory* could use some implementation-dependent magic,
+        ;; we will have logical pathnames already; otherwise,
+        ;; we only keep pathnames for which specifying the name and
+        ;; translating the LPN commute.
+        (loop :for f :in entries
+              :for p = (or (and (logical-pathname-p f) f)
+                           (let* ((u (ignore-errors (funcall merger f))))
+                             ;; The first u avoids a cumbersome (truename u) error.
+                             ;; At this point f should already be a truename,
+                             ;; but isn't quite in CLISP, for it doesn't have :version :newest
+                             (and u (equal (truename* u) (truename* f)) u)))
+              :when p :collect p)
+        entries))
+
+  (defun directory-files (directory &optional (pattern *wild-file*))
+    (let ((dir (pathname directory)))
+      (when (logical-pathname-p dir)
+        ;; Because of the filtering we do below,
+        ;; logical pathnames have restrictions on wild patterns.
+        ;; Not that the results are very portable when you use these patterns on physical pathnames.
+        (when (wild-pathname-p dir)
+          (error "Invalid wild pattern in logical directory ~S" directory))
+        (unless (member (pathname-directory pattern) '(() (:relative)) :test 'equal)
+          (error "Invalid file pattern ~S for logical directory ~S" pattern directory))
+        (setf pattern (make-pathname-logical pattern (pathname-host dir))))
+      (let ((entries (ignore-errors (directory* (merge-pathnames* pattern dir)))))
+        (filter-logical-directory-results
+         directory entries
+         #'(lambda (f)
+             (make-pathname :defaults dir
+                            :name (make-pathname-component-logical (pathname-name f))
+                            :type (make-pathname-component-logical (pathname-type f))
+                            :version (make-pathname-component-logical (pathname-version f))))))))
+
+  (defun subdirectories (directory)
+    (let* ((directory (ensure-directory-pathname directory))
+           #-(or abcl cormanlisp genera xcl)
+           (wild (merge-pathnames*
+                  #-(or abcl allegro cmu lispworks sbcl scl xcl)
+                  *wild-directory*
+                  #+(or abcl allegro cmu lispworks sbcl scl xcl) "*.*"
+                  directory))
+           (dirs
+             #-(or abcl cormanlisp genera xcl)
+             (ignore-errors
+              (directory* wild . #.(or #+clozure '(:directories t :files nil)
+                                       #+mcl '(:directories t))))
+             #+(or abcl xcl) (system:list-directory directory)
+             #+cormanlisp (cl::directory-subdirs directory)
+             #+genera (fs:directory-list directory))
+           #+(or abcl allegro cmu genera lispworks sbcl scl xcl)
+           (dirs (loop :for x :in dirs
+                       :for d = #+(or abcl xcl) (extensions:probe-directory x)
+                       #+allegro (excl:probe-directory x)
+                       #+(or cmu sbcl scl) (directory-pathname-p x)
+                       #+genera (getf (cdr x) :directory)
+                       #+lispworks (lw:file-directory-p x)
+                       :when d :collect #+(or abcl allegro xcl) d
+                         #+genera (ensure-directory-pathname (first x))
+                       #+(or cmu lispworks sbcl scl) x)))
       (filter-logical-directory-results
-       directory entries
-       #'(lambda (f)
-           (make-pathname :defaults dir
-                          :name (make-pathname-component-logical (pathname-name f))
-                          :type (make-pathname-component-logical (pathname-type f))
-                          :version (make-pathname-component-logical (pathname-version f))))))))
-
-(defun* subdirectories (directory)
-  (let* ((directory (ensure-directory-pathname directory))
-         #-(or abcl cormanlisp genera xcl)
-         (wild (merge-pathnames*
-                #-(or abcl allegro cmu lispworks sbcl scl xcl)
-                *wild-directory*
-                #+(or abcl allegro cmu lispworks sbcl scl xcl) "*.*"
-                directory))
-         (dirs
-          #-(or abcl cormanlisp genera xcl)
-          (ignore-errors
-            (directory* wild . #.(or #+clozure '(:directories t :files nil)
-                                     #+mcl '(:directories t))))
-          #+(or abcl xcl) (system:list-directory directory)
-          #+cormanlisp (cl::directory-subdirs directory)
-          #+genera (fs:directory-list directory))
-         #+(or abcl allegro cmu genera lispworks sbcl scl xcl)
-         (dirs (loop :for x :in dirs
-                 :for d = #+(or abcl xcl) (extensions:probe-directory x)
-                          #+allegro (excl:probe-directory x)
-                          #+(or cmu sbcl scl) (directory-pathname-p x)
-                          #+genera (getf (cdr x) :directory)
-                          #+lispworks (lw:file-directory-p x)
-                 :when d :collect #+(or abcl allegro xcl) d
-                                  #+genera (ensure-directory-pathname (first x))
-                                  #+(or cmu lispworks sbcl scl) x)))
-    (filter-logical-directory-results
-     directory dirs
-     (let ((prefix (or (normalize-pathname-directory-component (pathname-directory directory))
-                       '(:absolute)))) ; because allegro returns NIL for #p"FOO:"
-       #'(lambda (d)
-           (let ((dir (normalize-pathname-directory-component (pathname-directory d))))
-             (and (consp dir) (consp (cdr dir))
-                  (make-pathname
-                   :defaults directory :name nil :type nil :version nil
-                   :directory (append prefix (make-pathname-component-logical (last dir)))))))))))
-
-(defun* collect-sub*directories (directory collectp recursep collector)
-  (when (funcall collectp directory)
-    (funcall collector directory))
-  (dolist (subdir (subdirectories directory))
-    (when (funcall recursep subdir)
-      (collect-sub*directories subdir collectp recursep collector))))
-
-
-;;; Pathname host and its root
-(defun* pathname-root (pathname)
-  (make-pathname* :directory '(:absolute)
-                  :name nil :type nil :version nil
-                  :defaults pathname ;; host device, and on scl, *some*
-                  ;; scheme-specific parts: port username password, not others:
-                  . #.(or #+scl '(:parameters nil :query nil :fragment nil))))
-
-(defun* pathname-host-pathname (pathname)
-  (make-pathname* :directory nil
-                  :name nil :type nil :version nil :device nil
-                  :defaults pathname ;; host device, and on scl, *some*
-                  ;; scheme-specific parts: port username password, not others:
-                  . #.(or #+scl '(:parameters nil :query nil :fragment nil))))
-
-(defun* subpathp (maybe-subpath base-pathname)
-  (and (pathnamep maybe-subpath) (pathnamep base-pathname)
-       (absolute-pathname-p maybe-subpath) (absolute-pathname-p base-pathname)
-       (directory-pathname-p base-pathname) (not (wild-pathname-p base-pathname))
-       (pathname-equal (pathname-root maybe-subpath) (pathname-root base-pathname))
-       (with-pathname-defaults ()
-         (let ((enough (enough-namestring maybe-subpath base-pathname)))
-           (and (relative-pathname-p enough) (pathname enough))))))
-
-(defun* ensure-pathname-absolute (path &optional defaults (on-error 'error))
-  (cond
-    ((absolute-pathname-p path))
-    ((stringp path) (ensure-pathname-absolute (pathname path) defaults))
-    ((not (pathnamep path)) (call-function on-error "not a valid pathname designator ~S" path))
-    ((let ((default-pathname (if (pathnamep defaults) defaults (call-function defaults))))
-       (or (if (absolute-pathname-p default-pathname)
-               (absolute-pathname-p (merge-pathnames* path default-pathname))
-               (call-function on-error "Default pathname ~S is not an absolute pathname"
-                              default-pathname))
-           (call-function on-error "Failed to merge ~S with ~S into an absolute pathname"
-                          path default-pathname))))
-    (t (call-function on-error
-                      "Cannot ensure ~S is evaluated as an absolute pathname with defaults ~S"
-                      path defaults))))
-
+       directory dirs
+       (let ((prefix (or (normalize-pathname-directory-component (pathname-directory directory))
+                         '(:absolute)))) ; because allegro returns NIL for #p"FOO:"
+         #'(lambda (d)
+             (let ((dir (normalize-pathname-directory-component (pathname-directory d))))
+               (and (consp dir) (consp (cdr dir))
+                    (make-pathname
+                     :defaults directory :name nil :type nil :version nil
+                     :directory (append prefix (make-pathname-component-logical (last dir)))))))))))
+
+  (defun collect-sub*directories (directory collectp recursep collector)
+    (when (funcall collectp directory)
+      (funcall collector directory))
+    (dolist (subdir (subdirectories directory))
+      (when (funcall recursep subdir)
+        (collect-sub*directories subdir collectp recursep collector)))))
 
 ;;; Resolving symlinks somewhat
-(defun* truenamize (pathname)
-  "Resolve as much of a pathname as possible"
-  (block nil
-    (when (typep pathname '(or null logical-pathname)) (return pathname))
-    (let ((p pathname))
-      (unless (absolute-pathname-p p)
-        (setf p (or (absolute-pathname-p (ensure-pathname-absolute p 'get-pathname-defaults nil))
-                    (return p))))
-      (when (logical-pathname-p p) (return p))
-      (let ((found (probe-file* p :truename t)))
-        (when found (return found)))
-      (let* ((directory (normalize-pathname-directory-component (pathname-directory p)))
-             (up-components (reverse (rest directory)))
-             (down-components ()))
-        (assert (eq :absolute (first directory)))
-        (loop :while up-components :do
-          (if-let (parent (probe-file* (make-pathname* :directory `(:absolute ,@(reverse up-components))
-                                                       :name nil :type nil :version nil :defaults p)))
-            (return (merge-pathnames* (make-pathname* :directory `(:relative , at down-components)
-                                                      :defaults p)
-                                      (ensure-directory-pathname parent)))
-            (push (pop up-components) down-components))
-          :finally (return p))))))
+(with-upgradability ()
+  (defun truenamize (pathname)
+    "Resolve as much of a pathname as possible"
+    (block nil
+      (when (typep pathname '(or null logical-pathname)) (return pathname))
+      (let ((p pathname))
+        (unless (absolute-pathname-p p)
+          (setf p (or (absolute-pathname-p (ensure-absolute-pathname p 'get-pathname-defaults nil))
+                      (return p))))
+        (when (logical-pathname-p p) (return p))
+        (let ((found (probe-file* p :truename t)))
+          (when found (return found)))
+        (let* ((directory (normalize-pathname-directory-component (pathname-directory p)))
+               (up-components (reverse (rest directory)))
+               (down-components ()))
+          (assert (eq :absolute (first directory)))
+          (loop :while up-components :do
+            (if-let (parent (probe-file* (make-pathname* :directory `(:absolute ,@(reverse up-components))
+                                                         :name nil :type nil :version nil :defaults p)))
+              (return (merge-pathnames* (make-pathname* :directory `(:relative , at down-components)
+                                                        :defaults p)
+                                        (ensure-directory-pathname parent)))
+              (push (pop up-components) down-components))
+                :finally (return p))))))
+
+  (defun resolve-symlinks (path)
+    #-allegro (truenamize path)
+    #+allegro
+    (if (physical-pathname-p path)
+        (or (ignore-errors (excl:pathname-resolve-symbolic-links path)) path)
+        path))
 
-(defun* resolve-symlinks (path)
-  #-allegro (truenamize path)
-  #+allegro
-  (if (physical-pathname-p path)
-      (or (ignore-errors (excl:pathname-resolve-symbolic-links path)) path)
-      path))
-
-(defun* resolve-symlinks* (path)
-  (if *resolve-symlinks*
-      (and path (resolve-symlinks path))
-      path))
+  (defvar *resolve-symlinks* t
+    "Determine whether or not ASDF resolves symlinks when defining systems.
+Defaults to T.")
 
+  (defun resolve-symlinks* (path)
+    (if *resolve-symlinks*
+        (and path (resolve-symlinks path))
+        path)))
 
-;;; Check pathname constraints
 
-(defun* ensure-pathname
-    (pathname &key
-              on-error
-              defaults type dot-dot
-              want-pathname
-              want-logical want-physical ensure-physical
-              want-relative want-absolute ensure-absolute ensure-subpath
-              want-non-wild want-wild wilden
-              want-file want-directory ensure-directory
-              want-existing ensure-directories-exist
-              truename resolve-symlinks truenamize
-              &aux (p pathname)) ;; mutable working copy, preserve original
-  "Coerces its argument into a PATHNAME,
+;;; Check pathname constraints
+(with-upgradability ()
+  (defun ensure-pathname
+      (pathname &key
+                  on-error
+                  defaults type dot-dot
+                  want-pathname
+                  want-logical want-physical ensure-physical
+                  want-relative want-absolute ensure-absolute ensure-subpath
+                  want-non-wild want-wild wilden
+                  want-file want-directory ensure-directory
+                  want-existing ensure-directories-exist
+                  truename resolve-symlinks truenamize
+       &aux (p pathname)) ;; mutable working copy, preserve original
+    "Coerces its argument into a PATHNAME,
 optionally doing some transformations and checking specified constraints.
 
 If the argument is NIL, then NIL is returned unless the WANT-PATHNAME constraint is specified.
@@ -2506,216 +2724,151 @@
 TRUENAME replaces the pathname by its truename, or errors if not possible.
 RESOLVE-SYMLINKS replaces the pathname by a variant with symlinks resolved by RESOLVE-SYMLINKS.
 TRUENAMIZE uses TRUENAMIZE to resolve as many symlinks as possible."
-  (block nil
-    (flet ((report-error (keyword description &rest arguments)
-             (call-function (or on-error 'error)
-                            "Invalid pathname ~S: ~*~?"
-                            pathname keyword description arguments)))
-      (macrolet ((err (constraint &rest arguments)
-                   `(report-error ',(intern* constraint :keyword) , at arguments))
-                 (check (constraint condition &rest arguments)
-                   `(when ,constraint
-                      (unless ,condition (err ,constraint , at arguments))))
-                 (transform (transform condition expr)
-                   `(when ,transform
-                      (,@(if condition `(when ,condition) '(progn))
-                       (setf p ,expr)))))
-        (etypecase p
-          ((or null pathname))
-          (string
-           (setf p (parse-unix-namestring
-                    p :defaults defaults :type type :dot-dot dot-dot
-                    :ensure-directory ensure-directory :want-relative want-relative))))
-        (check want-pathname (pathnamep p) "Expected a pathname, not NIL")
-        (unless (pathnamep p) (return nil))
-        (check want-logical (logical-pathname-p p) "Expected a logical pathname")
-        (check want-physical (physical-pathname-p p) "Expected a physical pathname")
-        (transform ensure-physical () (translate-logical-pathname p))
-        (check ensure-physical (physical-pathname-p p) "Could not translate to a physical pathname")
-        (check want-relative (relative-pathname-p p) "Expected a relative pathname")
-        (check want-absolute (absolute-pathname-p p) "Expected an absolute pathname")
-        (transform ensure-absolute (not (absolute-pathname-p p)) (merge-pathnames* p defaults))
-        (check ensure-absolute (absolute-pathname-p p)
-               "Could not make into an absolute pathname even after merging with ~S" defaults)
-        (check ensure-subpath (absolute-pathname-p defaults)
-               "cannot be checked to be a subpath of non-absolute pathname ~S" defaults)
-        (check ensure-subpath (subpathp p defaults) "is not a sub pathname of ~S" defaults)
-        (check want-file (file-pathname-p p) "Expected a file pathname")
-        (check want-directory (directory-pathname-p p) "Expected a directory pathname")
-        (transform ensure-directory (not (directory-pathname-p p)) (ensure-directory-pathname p))
-        (check want-non-wild (not (wild-pathname-p p)) "Expected a non-wildcard pathname")
-        (check want-wild (wild-pathname-p p) "Expected a wildcard pathname")
-        (transform wilden (not (wild-pathname-p p)) (wilden p))
-        (when want-existing
-          (let ((existing (probe-file* p :truename truename)))
-            (if existing
-                (when truename
-                  (return existing))
-                (err want-existing "Expected an existing pathname"))))
-        (when ensure-directories-exist (ensure-directories-exist p))
-        (when truename
-          (let ((truename (truename* p)))
-            (if truename
-                (return truename)
-                (err truename "Can't get a truename for pathname"))))
-        (transform resolve-symlinks () (resolve-symlinks p))
-        (transform truenamize () (truenamize p))
-        p))))
+    (block nil
+      (flet ((report-error (keyword description &rest arguments)
+               (call-function (or on-error 'error)
+                              "Invalid pathname ~S: ~*~?"
+                              pathname keyword description arguments)))
+        (macrolet ((err (constraint &rest arguments)
+                     `(report-error ',(intern* constraint :keyword) , at arguments))
+                   (check (constraint condition &rest arguments)
+                     `(when ,constraint
+                        (unless ,condition (err ,constraint , at arguments))))
+                   (transform (transform condition expr)
+                     `(when ,transform
+                        (,@(if condition `(when ,condition) '(progn))
+                         (setf p ,expr)))))
+          (etypecase p
+            ((or null pathname))
+            (string
+             (setf p (parse-unix-namestring
+                      p :defaults defaults :type type :dot-dot dot-dot
+                        :ensure-directory ensure-directory :want-relative want-relative))))
+          (check want-pathname (pathnamep p) "Expected a pathname, not NIL")
+          (unless (pathnamep p) (return nil))
+          (check want-logical (logical-pathname-p p) "Expected a logical pathname")
+          (check want-physical (physical-pathname-p p) "Expected a physical pathname")
+          (transform ensure-physical () (translate-logical-pathname p))
+          (check ensure-physical (physical-pathname-p p) "Could not translate to a physical pathname")
+          (check want-relative (relative-pathname-p p) "Expected a relative pathname")
+          (check want-absolute (absolute-pathname-p p) "Expected an absolute pathname")
+          (transform ensure-absolute (not (absolute-pathname-p p)) (merge-pathnames* p defaults))
+          (check ensure-absolute (absolute-pathname-p p)
+                 "Could not make into an absolute pathname even after merging with ~S" defaults)
+          (check ensure-subpath (absolute-pathname-p defaults)
+                 "cannot be checked to be a subpath of non-absolute pathname ~S" defaults)
+          (check ensure-subpath (subpathp p defaults) "is not a sub pathname of ~S" defaults)
+          (check want-file (file-pathname-p p) "Expected a file pathname")
+          (check want-directory (directory-pathname-p p) "Expected a directory pathname")
+          (transform ensure-directory (not (directory-pathname-p p)) (ensure-directory-pathname p))
+          (check want-non-wild (not (wild-pathname-p p)) "Expected a non-wildcard pathname")
+          (check want-wild (wild-pathname-p p) "Expected a wildcard pathname")
+          (transform wilden (not (wild-pathname-p p)) (wilden p))
+          (when want-existing
+            (let ((existing (probe-file* p :truename truename)))
+              (if existing
+                  (when truename
+                    (return existing))
+                  (err want-existing "Expected an existing pathname"))))
+          (when ensure-directories-exist (ensure-directories-exist p))
+          (when truename
+            (let ((truename (truename* p)))
+              (if truename
+                  (return truename)
+                  (err truename "Can't get a truename for pathname"))))
+          (transform resolve-symlinks () (resolve-symlinks p))
+          (transform truenamize () (truenamize p))
+          p)))))
+
+
+;;; Pathname defaults
+(with-upgradability ()
+  (defun get-pathname-defaults (&optional (defaults *default-pathname-defaults*))
+    (or (absolute-pathname-p defaults)
+        (merge-pathnames* defaults (getcwd))))
+
+  (defun call-with-current-directory (dir thunk)
+    (if dir
+        (let* ((dir (resolve-symlinks* (get-pathname-defaults (pathname-directory-pathname dir))))
+               (*default-pathname-defaults* dir)
+               (cwd (getcwd)))
+          (chdir dir)
+          (unwind-protect
+               (funcall thunk)
+            (chdir cwd)))
+        (funcall thunk)))
+
+  (defmacro with-current-directory ((&optional dir) &body body)
+    "Call BODY while the POSIX current working directory is set to DIR"
+    `(call-with-current-directory ,dir #'(lambda () , at body))))
 
 
 ;;; Environment pathnames
-(defun* inter-directory-separator ()
-  (if (os-unix-p) #\: #\;))
-
-(defun* split-native-pathnames-string (string &rest constraints &key &allow-other-keys)
-  (loop :for namestring :in (split-string string :separator (string (inter-directory-separator)))
-        :collect (apply 'parse-native-namestring namestring constraints)))
-
-(defun* getenv-pathname (x &rest constraints &key on-error &allow-other-keys)
-  (apply 'parse-native-namestring (getenvp x)
-         :on-error (or on-error
-                       `(error "In (~S ~S), invalid pathname ~*~S: ~*~?" getenv-pathname ,x))
-         constraints))
-(defun* getenv-pathnames (x &rest constraints &key on-error &allow-other-keys)
-  (apply 'split-native-pathnames-string (getenvp x)
-         :on-error (or on-error
-                       `(error "In (~S ~S), invalid pathname ~*~S: ~*~?" getenv-pathnames ,x))
-         constraints))
-(defun* getenv-absolute-directory (x)
-  (getenv-pathname x :want-absolute t :ensure-directory t))
-(defun* getenv-absolute-directories (x)
-  (getenv-pathnames x :want-absolute t :ensure-directory t))
-
-(defun* lisp-implementation-directory (&key truename)
-  (let ((dir
-          (ignore-errors
-           #+clozure #p"ccl:"
-           #+(or ecl mkcl) #p"SYS:"
-           #+gcl system::*system-directory*
-           #+sbcl (if-let (it (find-symbol* :sbcl-homedir-pathname :sb-int nil))
-                     (funcall it)
-                     (getenv-pathname "SBCL_HOME" :ensure-directory t)))))
-    (if (and dir truename)
-        (truename* dir)
-        dir)))
-
-(defun* lisp-implementation-pathname-p (pathname)
-  ;; Other builtin systems are those under the implementation directory
-  (and (when pathname
-         (if-let (impdir (lisp-implementation-directory))
-           (or (subpathp pathname impdir)
-               (when *resolve-symlinks*
-                 (if-let (truename (truename* pathname))
-                   (if-let (trueimpdir (truename* impdir))
-                     (subpathp truename trueimpdir)))))))
-       t))
-
-
-;;; Pathname defaults and current directory
-(defun* get-pathname-defaults (&optional (defaults *default-pathname-defaults*))
-  (or (absolute-pathname-p defaults)
-      (merge-pathnames* defaults (getcwd))))
-
-(defun* call-with-current-directory (dir thunk)
-  (if dir
-      (let* ((dir (resolve-symlinks* (get-pathname-defaults (pathname-directory-pathname dir))))
-             (*default-pathname-defaults* dir)
-             (cwd (getcwd)))
-        (chdir dir)
-        (unwind-protect
-             (funcall thunk)
-          (chdir cwd)))
-      (funcall thunk)))
-
-(defmacro with-current-directory ((&optional dir) &body body)
-  "Call BODY while the POSIX current working directory is set to DIR"
-  `(call-with-current-directory ,dir #'(lambda () , at body)))
-
-
-;;; Translate a pathname
-(defun relativize-directory-component (directory-component)
-  (let ((directory (normalize-pathname-directory-component directory-component)))
-    (cond
-      ((stringp directory)
-       (list :relative directory))
-      ((eq (car directory) :absolute)
-       (cons :relative (cdr directory)))
-      (t
-       directory))))
+(with-upgradability ()
+  (defun inter-directory-separator ()
+    (if (os-unix-p) #\: #\;))
+
+  (defun split-native-pathnames-string (string &rest constraints &key &allow-other-keys)
+    (loop :for namestring :in (split-string string :separator (string (inter-directory-separator)))
+          :collect (apply 'parse-native-namestring namestring constraints)))
+
+  (defun getenv-pathname (x &rest constraints &key on-error &allow-other-keys)
+    (apply 'parse-native-namestring (getenvp x)
+           :on-error (or on-error
+                         `(error "In (~S ~S), invalid pathname ~*~S: ~*~?" getenv-pathname ,x))
+           constraints))
+  (defun getenv-pathnames (x &rest constraints &key on-error &allow-other-keys)
+    (apply 'split-native-pathnames-string (getenvp x)
+           :on-error (or on-error
+                         `(error "In (~S ~S), invalid pathname ~*~S: ~*~?" getenv-pathnames ,x))
+           constraints))
+  (defun getenv-absolute-directory (x)
+    (getenv-pathname x :want-absolute t :ensure-directory t))
+  (defun getenv-absolute-directories (x)
+    (getenv-pathnames x :want-absolute t :ensure-directory t))
+
+  (defun lisp-implementation-directory (&key truename)
+    (declare (ignorable truename))
+    #+(or clozure ecl gcl mkcl sbcl)
+    (let ((dir
+            (ignore-errors
+             #+clozure #p"ccl:"
+             #+(or ecl mkcl) #p"SYS:"
+             #+gcl system::*system-directory*
+             #+sbcl (if-let (it (find-symbol* :sbcl-homedir-pathname :sb-int nil))
+                      (funcall it)
+                      (getenv-pathname "SBCL_HOME" :ensure-directory t)))))
+      (if (and dir truename)
+          (truename* dir)
+          dir)))
+
+  (defun lisp-implementation-pathname-p (pathname)
+    ;; Other builtin systems are those under the implementation directory
+    (and (when pathname
+           (if-let (impdir (lisp-implementation-directory))
+             (or (subpathp pathname impdir)
+                 (when *resolve-symlinks*
+                   (if-let (truename (truename* pathname))
+                     (if-let (trueimpdir (truename* impdir))
+                       (subpathp truename trueimpdir)))))))
+         t)))
 
-(defun* relativize-pathname-directory (pathspec)
-  (let ((p (pathname pathspec)))
-    (make-pathname*
-     :directory (relativize-directory-component (pathname-directory p))
-     :defaults p)))
 
-(defun* directory-separator-for-host (&optional (pathname *default-pathname-defaults*))
-  (let ((foo (make-pathname* :directory '(:absolute "FOO") :defaults pathname)))
-    (last-char (namestring foo))))
-
-#-scl
-(defun* directorize-pathname-host-device (pathname)
-  #+(or unix abcl)
-  (when (and #+abcl (os-unix-p) (physical-pathname-p pathname))
-    (return-from directorize-pathname-host-device pathname))
-  (let* ((root (pathname-root pathname))
-         (wild-root (wilden root))
-         (absolute-pathname (merge-pathnames* pathname root))
-         (separator (directory-separator-for-host root))
-         (root-namestring (namestring root))
-         (root-string
-          (substitute-if #\/
-                         #'(lambda (x) (or (eql x #\:)
-                                           (eql x separator)))
-                         root-namestring)))
-    (multiple-value-bind (relative path filename)
-        (split-unix-namestring-directory-components root-string :ensure-directory t)
-      (declare (ignore relative filename))
-      (let ((new-base
-             (make-pathname* :defaults root :directory `(:absolute , at path))))
-        (translate-pathname absolute-pathname wild-root (wilden new-base))))))
-
-#+scl
-(defun* directorize-pathname-host-device (pathname)
-  (let ((scheme (ext:pathname-scheme pathname))
-        (host (pathname-host pathname))
-        (port (ext:pathname-port pathname))
-        (directory (pathname-directory pathname)))
-    (flet ((specificp (x) (and x (not (eq x :unspecific)))))
-      (if (or (specificp port)
-              (and (specificp host) (plusp (length host)))
-              (specificp scheme))
-        (let ((prefix ""))
-          (when (specificp port)
-            (setf prefix (format nil ":~D" port)))
-          (when (and (specificp host) (plusp (length host)))
-            (setf prefix (strcat host prefix)))
-          (setf prefix (strcat ":" prefix))
-          (when (specificp scheme)
-            (setf prefix (strcat scheme prefix)))
-          (assert (and directory (eq (first directory) :absolute)))
-          (make-pathname* :directory `(:absolute ,prefix ,@(rest directory))
-                          :defaults pathname)))
-    pathname)))
-
-(defun* (translate-pathname*) (path absolute-source destination &optional root source)
-  (declare (ignore source))
-  (cond
-    ((functionp destination)
-     (funcall destination path absolute-source))
-    ((eq destination t)
-     path)
-    ((not (pathnamep destination))
-     (error "Invalid destination"))
-    ((not (absolute-pathname-p destination))
-     (translate-pathname path absolute-source (merge-pathnames* destination root)))
-    (root
-     (translate-pathname (directorize-pathname-host-device path) absolute-source destination))
-    (t
-     (translate-pathname path absolute-source destination))))
+;;; Simple filesystem operations
+(with-upgradability ()
+  (defun ensure-all-directories-exist (pathnames)
+    (dolist (pathname pathnames)
+      (ensure-directories-exist (translate-logical-pathname pathname))))
+
+  (defun rename-file-overwriting-target (source target)
+    #+clisp ;; But for a bug in CLISP 2.48, we should use :if-exists :overwrite and be atomic
+    (posix:copy-file source target :method :rename)
+    #-clisp
+    (rename-file source target
+                 #+clozure :if-exists #+clozure :rename-and-delete))
 
-;;; Hook for output translations
-(defvar *output-translation-function* 'identity)
+  (defun delete-file-if-exists (x)
+    (when x (handler-case (delete-file x) (file-error () nil)))))
 
 
 ;;;; ---------------------------------------------------------------------------
@@ -2723,9 +2876,12 @@
 
 (asdf/package:define-package :asdf/stream
   (:recycle :asdf/stream)
-  (:use :asdf/common-lisp :asdf/package :asdf/utility :asdf/os :asdf/pathname)
+  (:use :asdf/common-lisp :asdf/package :asdf/utility :asdf/os :asdf/pathname :asdf/filesystem)
   (:export
    #:*default-stream-element-type* #:*stderr* #:setup-stderr
+   #:detect-encoding #:*encoding-detection-hook* #:always-default-encoding
+   #:encoding-external-format #:*encoding-external-format-hook* #:default-encoding-external-format
+   #:*default-encoding* #:*utf-8-external-format*
    #:with-safe-io-syntax #:call-with-safe-io-syntax
    #:with-output #:output-string #:with-input
    #:with-input-file #:call-with-input-file
@@ -2736,12 +2892,7 @@
    #:slurp-stream-forms #:slurp-stream-form
    #:read-file-string #:read-file-lines #:read-file-forms #:read-file-form #:safe-read-file-form
    #:eval-input #:eval-thunk #:standard-eval-thunk
-   #:detect-encoding #:*encoding-detection-hook* #:always-default-encoding
-   #:encoding-external-format #:*encoding-external-format-hook* #:default-encoding-external-format
-   #:*default-encoding* #:*utf-8-external-format*
-   #:ensure-all-directories-exist
-   #:rename-file-overwriting-target
-   #:delete-file-if-exists
+   ;; Temporary files
    #:*temporary-directory* #:temporary-directory #:default-temporary-directory
    #:setup-temporary-directory
    #:call-with-temporary-file #:with-temporary-file
@@ -2749,186 +2900,234 @@
    #:call-with-staging-pathname #:with-staging-pathname))
 (in-package :asdf/stream)
 
-(defvar *default-stream-element-type* (or #+(or abcl cmu cormanlisp scl xcl) 'character :default)
-  "default element-type for open (depends on the current CL implementation)")
+(with-upgradability ()
+  (defvar *default-stream-element-type* (or #+(or abcl cmu cormanlisp scl xcl) 'character :default)
+    "default element-type for open (depends on the current CL implementation)")
+
+  (defvar *stderr* *error-output*
+    "the original error output stream at startup")
+
+  (defun setup-stderr ()
+    (setf *stderr*
+          #+allegro excl::*stderr*
+          #+clozure ccl::*stderr*
+          #-(or allegro clozure) *error-output*))
+  (setup-stderr))
+
+
+;;; Encodings (mostly hooks only; full support requires asdf-encodings)
+(with-upgradability ()
+  (defvar *default-encoding* :default
+    "Default encoding for source files.
+The default value :default preserves the legacy behavior.
+A future default might be :utf-8 or :autodetect
+reading emacs-style -*- coding: utf-8 -*- specifications,
+and falling back to utf-8 or latin1 if nothing is specified.")
 
-(defvar *stderr* *error-output*
-  "the original error output stream at startup")
+  (defparameter *utf-8-external-format*
+    #+(and asdf-unicode (not clisp)) :utf-8
+    #+(and asdf-unicode clisp) charset:utf-8
+    #-asdf-unicode :default
+    "Default :external-format argument to pass to CL:OPEN and also
+CL:LOAD or CL:COMPILE-FILE to best process a UTF-8 encoded file.
+On modern implementations, this will decode UTF-8 code points as CL characters.
+On legacy implementations, it may fall back on some 8-bit encoding,
+with non-ASCII code points being read as several CL characters;
+hopefully, if done consistently, that won't affect program behavior too much.")
 
-(defun setup-stderr ()
-  (setf *stderr*
-        #+allegro excl::*stderr*
-        #+clozure ccl::*stderr*
-        #-(or allegro clozure) *error-output*))
-(setup-stderr)
+  (defun always-default-encoding (pathname)
+    (declare (ignore pathname))
+    *default-encoding*)
+
+  (defvar *encoding-detection-hook* #'always-default-encoding
+    "Hook for an extension to define a function to automatically detect a file's encoding")
+
+  (defun detect-encoding (pathname)
+    (if (and pathname (not (directory-pathname-p pathname)) (probe-file* pathname))
+        (funcall *encoding-detection-hook* pathname)
+        *default-encoding*))
+
+  (defun default-encoding-external-format (encoding)
+    (case encoding
+      (:default :default) ;; for backward-compatibility only. Explicit usage discouraged.
+      (:utf-8 *utf-8-external-format*)
+      (otherwise
+       (cerror "Continue using :external-format :default" (compatfmt "~@<Your ASDF component is using encoding ~S but it isn't recognized. Your system should :defsystem-depends-on (:asdf-encodings).~:>") encoding)
+       :default)))
+
+  (defvar *encoding-external-format-hook*
+    #'default-encoding-external-format
+    "Hook for an extension to define a mapping between non-default encodings
+and implementation-defined external-format's")
 
+  (defun encoding-external-format (encoding)
+    (funcall *encoding-external-format-hook* encoding)))
 
-;;; Safe syntax
 
-(defvar *standard-readtable* (copy-readtable nil))
+;;; Safe syntax
+(with-upgradability ()
+  (defvar *standard-readtable* (copy-readtable nil))
 
-(defmacro with-safe-io-syntax ((&key (package :cl)) &body body)
-  "Establish safe CL reader options around the evaluation of BODY"
-  `(call-with-safe-io-syntax #'(lambda () (let ((*package* (find-package ,package))) , at body))))
-
-(defun* call-with-safe-io-syntax (thunk &key (package :cl))
-  (with-standard-io-syntax ()
-    (let ((*package* (find-package package))
-          (*readtable* *standard-readtable*)
-          (*read-default-float-format* 'double-float)
-          (*print-readably* nil)
-	  (*read-eval* nil))
-      (funcall thunk))))
+  (defmacro with-safe-io-syntax ((&key (package :cl)) &body body)
+    "Establish safe CL reader options around the evaluation of BODY"
+    `(call-with-safe-io-syntax #'(lambda () (let ((*package* (find-package ,package))) , at body))))
+
+  (defun call-with-safe-io-syntax (thunk &key (package :cl))
+    (with-standard-io-syntax
+      (let ((*package* (find-package package))
+            (*read-default-float-format* 'double-float)
+            (*print-readably* nil)
+            (*read-eval* nil))
+        (funcall thunk)))))
 
 
 ;;; Output to a stream or string, FORMAT-style
-
-(defun* call-with-output (output function)
-  "Calls FUNCTION with an actual stream argument,
+(with-upgradability ()
+  (defun call-with-output (output function)
+    "Calls FUNCTION with an actual stream argument,
 behaving like FORMAT with respect to how stream designators are interpreted:
 If OUTPUT is a stream, use it as the stream.
 If OUTPUT is NIL, use a STRING-OUTPUT-STREAM as the stream, and return the resulting string.
 If OUTPUT is T, use *STANDARD-OUTPUT* as the stream.
 If OUTPUT is a string with a fill-pointer, use it as a string-output-stream.
 Otherwise, signal an error."
-  (etypecase output
-    (null
-     (with-output-to-string (stream) (funcall function stream)))
-    ((eql t)
-     (funcall function *standard-output*))
-    (stream
-     (funcall function output))
-    (string
-     (assert (fill-pointer output))
-     (with-output-to-string (stream output) (funcall function stream)))))
+    (etypecase output
+      (null
+       (with-output-to-string (stream) (funcall function stream)))
+      ((eql t)
+       (funcall function *standard-output*))
+      (stream
+       (funcall function output))
+      (string
+       (assert (fill-pointer output))
+       (with-output-to-string (stream output) (funcall function stream)))))
 
-(defmacro with-output ((output-var &optional (value output-var)) &body body)
-  "Bind OUTPUT-VAR to an output stream, coercing VALUE (default: previous binding of OUTPUT-VAR)
+  (defmacro with-output ((output-var &optional (value output-var)) &body body)
+    "Bind OUTPUT-VAR to an output stream, coercing VALUE (default: previous binding of OUTPUT-VAR)
 as per FORMAT, and evaluate BODY within the scope of this binding."
-  `(call-with-output ,value #'(lambda (,output-var) , at body)))
+    `(call-with-output ,value #'(lambda (,output-var) , at body)))
 
-(defun* output-string (string &optional output)
-  "If the desired OUTPUT is not NIL, print the string to the output; otherwise return the string"
-  (if output
-      (with-output (output) (princ string output))
-      string))
+  (defun output-string (string &optional output)
+    "If the desired OUTPUT is not NIL, print the string to the output; otherwise return the string"
+    (if output
+        (with-output (output) (princ string output))
+        string)))
 
 
 ;;; Input helpers
-
-(defun* call-with-input (input function)
-  "Calls FUNCTION with an actual stream argument, interpreting
+(with-upgradability ()
+  (defun call-with-input (input function)
+    "Calls FUNCTION with an actual stream argument, interpreting
 stream designators like READ, but also coercing strings to STRING-INPUT-STREAM.
 If INPUT is a STREAM, use it as the stream.
 If INPUT is NIL, use a *STANDARD-INPUT* as the stream.
 If INPUT is T, use *TERMINAL-IO* as the stream.
 As an extension, if INPUT is a string, use it as a string-input-stream.
 Otherwise, signal an error."
-  (etypecase input
-    (null (funcall function *standard-input*))
-    ((eql t) (funcall function *terminal-io*))
-    (stream (funcall function input))
-    (string (with-input-from-string (stream input) (funcall function stream)))))
+    (etypecase input
+      (null (funcall function *standard-input*))
+      ((eql t) (funcall function *terminal-io*))
+      (stream (funcall function input))
+      (string (with-input-from-string (stream input) (funcall function stream)))))
 
-(defmacro with-input ((input-var &optional (value input-var)) &body body)
-  "Bind INPUT-VAR to an input stream, coercing VALUE (default: previous binding of INPUT-VAR)
+  (defmacro with-input ((input-var &optional (value input-var)) &body body)
+    "Bind INPUT-VAR to an input stream, coercing VALUE (default: previous binding of INPUT-VAR)
 as per CALL-WITH-INPUT, and evaluate BODY within the scope of this binding."
-  `(call-with-input ,value #'(lambda (,input-var) , at body)))
+    `(call-with-input ,value #'(lambda (,input-var) , at body)))
 
-(defun* call-with-input-file (pathname thunk
-                                       &key
-                                       (element-type *default-stream-element-type*)
-                                       (external-format :default)
-                                       (if-does-not-exist :error))
-  "Open FILE for input with given recognizes options, call THUNK with the resulting stream.
+  (defun call-with-input-file (pathname thunk
+                               &key
+                                 (element-type *default-stream-element-type*)
+                                 (external-format *utf-8-external-format*)
+                                 (if-does-not-exist :error))
+    "Open FILE for input with given recognizes options, call THUNK with the resulting stream.
 Other keys are accepted but discarded."
-  #+gcl2.6 (declare (ignore external-format))
-  (with-open-file (s pathname :direction :input
-                     :element-type element-type
-                     #-gcl2.6 :external-format #-gcl2.6 external-format
-                     :if-does-not-exist if-does-not-exist)
-    (funcall thunk s)))
-
-(defmacro with-input-file ((var pathname &rest keys &key element-type external-format) &body body)
-  (declare (ignore element-type external-format))
-  `(call-with-input-file ,pathname #'(lambda (,var) , at body) , at keys))
+    #+gcl2.6 (declare (ignore external-format))
+    (with-open-file (s pathname :direction :input
+                                :element-type element-type
+                                #-gcl2.6 :external-format #-gcl2.6 external-format
+                                :if-does-not-exist if-does-not-exist)
+      (funcall thunk s)))
+
+  (defmacro with-input-file ((var pathname &rest keys &key element-type external-format) &body body)
+    (declare (ignore element-type external-format))
+    `(call-with-input-file ,pathname #'(lambda (,var) , at body) , at keys)))
 
 
 ;;; Ensure output buffers are flushed
-
-(defun* finish-outputs (&rest streams)
-  "Finish output on the main output streams as well as any specified one.
+(with-upgradability ()
+  (defun finish-outputs (&rest streams)
+    "Finish output on the main output streams as well as any specified one.
 Useful for portably flushing I/O before user input or program exit."
-  ;; CCL notably buffers its stream output by default.
-  (dolist (s (append streams
-                     (list *stderr* *error-output* *standard-output* *trace-output*
-                           *debug-io* *terminal-io* *debug-io* *query-io*)))
-    (ignore-errors (finish-output s)))
-  (values))
-
-(defun* format! (stream format &rest args)
-  "Just like format, but call finish-outputs before and after the output."
-  (finish-outputs stream)
-  (apply 'format stream format args)
-  (finish-output stream))
-
-(defun* safe-format! (stream format &rest args)
-  (with-safe-io-syntax ()
-    (ignore-errors (apply 'format! stream format args))
-    (finish-outputs stream))) ; just in case format failed
-
+    ;; CCL notably buffers its stream output by default.
+    (dolist (s (append streams
+                       (list *stderr* *error-output* *standard-output* *trace-output*
+                             *debug-io* *terminal-io* *debug-io* *query-io*)))
+      (ignore-errors (finish-output s)))
+    (values))
+
+  (defun format! (stream format &rest args)
+    "Just like format, but call finish-outputs before and after the output."
+    (finish-outputs stream)
+    (apply 'format stream format args)
+    (finish-output stream))
 
-;;; Simple Whole-Stream processing
+  (defun safe-format! (stream format &rest args)
+    (with-safe-io-syntax ()
+      (ignore-errors (apply 'format! stream format args))
+      (finish-outputs stream)))) ; just in case format failed
 
 
-(defun* copy-stream-to-stream (input output &key element-type buffer-size linewise prefix)
-  "Copy the contents of the INPUT stream into the OUTPUT stream.
+;;; Simple Whole-Stream processing
+(with-upgradability ()
+  (defun copy-stream-to-stream (input output &key element-type buffer-size linewise prefix)
+    "Copy the contents of the INPUT stream into the OUTPUT stream.
 If LINEWISE is true, then read and copy the stream line by line, with an optional PREFIX.
 Otherwise, using WRITE-SEQUENCE using a buffer of size BUFFER-SIZE."
-  (with-open-stream (input input)
-    (if linewise
-        (loop* :for (line eof) = (multiple-value-list (read-line input nil nil))
-               :while line :do
-               (when prefix (princ prefix output))
-               (princ line output)
-               (unless eof (terpri output))
-               (finish-output output)
-               (when eof (return)))
-        (loop
-          :with buffer-size = (or buffer-size 8192)
-          :for buffer = (make-array (list buffer-size) :element-type (or element-type 'character))
-          :for end = (read-sequence buffer input)
-          :until (zerop end)
-          :do (write-sequence buffer output :end end)
-              (when (< end buffer-size) (return))))))
-
-(defun* concatenate-files (inputs output)
-  (with-open-file (o output :element-type '(unsigned-byte 8)
-                            :direction :output :if-exists :rename-and-delete)
-    (dolist (input inputs)
-      (with-open-file (i input :element-type '(unsigned-byte 8)
-                               :direction :input :if-does-not-exist :error)
-        (copy-stream-to-stream i o :element-type '(unsigned-byte 8))))))
-
-(defun* slurp-stream-string (input &key (element-type 'character))
-  "Read the contents of the INPUT stream as a string"
-  (with-open-stream (input input)
-    (with-output-to-string (output)
-      (copy-stream-to-stream input output :element-type element-type))))
+    (with-open-stream (input input)
+      (if linewise
+          (loop* :for (line eof) = (multiple-value-list (read-line input nil nil))
+                 :while line :do
+                 (when prefix (princ prefix output))
+                 (princ line output)
+                 (unless eof (terpri output))
+                 (finish-output output)
+                 (when eof (return)))
+          (loop
+            :with buffer-size = (or buffer-size 8192)
+            :for buffer = (make-array (list buffer-size) :element-type (or element-type 'character))
+            :for end = (read-sequence buffer input)
+            :until (zerop end)
+            :do (write-sequence buffer output :end end)
+                (when (< end buffer-size) (return))))))
+
+  (defun concatenate-files (inputs output)
+    (with-open-file (o output :element-type '(unsigned-byte 8)
+                              :direction :output :if-exists :rename-and-delete)
+      (dolist (input inputs)
+        (with-open-file (i input :element-type '(unsigned-byte 8)
+                                 :direction :input :if-does-not-exist :error)
+          (copy-stream-to-stream i o :element-type '(unsigned-byte 8))))))
+
+  (defun slurp-stream-string (input &key (element-type 'character))
+    "Read the contents of the INPUT stream as a string"
+    (with-open-stream (input input)
+      (with-output-to-string (output)
+        (copy-stream-to-stream input output :element-type element-type))))
 
-(defun* slurp-stream-lines (input &key count)
-  "Read the contents of the INPUT stream as a list of lines, return those lines.
+  (defun slurp-stream-lines (input &key count)
+    "Read the contents of the INPUT stream as a list of lines, return those lines.
 
 Read no more than COUNT lines."
-  (check-type count (or null integer))
-  (with-open-stream (input input)
-    (loop :for n :from 0
-          :for l = (and (or (not count) (< n count))
-                        (read-line input nil nil))
-          :while l :collect l)))
+    (check-type count (or null integer))
+    (with-open-stream (input input)
+      (loop :for n :from 0
+            :for l = (and (or (not count) (< n count))
+                          (read-line input nil nil))
+            :while l :collect l)))
 
-(defun* slurp-stream-line (input &key (at 0))
-  "Read the contents of the INPUT stream as a list of lines,
+  (defun slurp-stream-line (input &key (at 0))
+    "Read the contents of the INPUT stream as a list of lines,
 then return the ACCESS-AT of that list of lines using the AT specifier.
 PATH defaults to 0, i.e. return the first line.
 PATH is typically an integer, or a list of an integer and a function.
@@ -2937,26 +3136,26 @@
 The stream will not be read beyond the Nth lines,
 where N is the index specified by path
 if path is either an integer or a list that starts with an integer."
-  (access-at (slurp-stream-lines input :count (access-at-count at)) at))
+    (access-at (slurp-stream-lines input :count (access-at-count at)) at))
 
-(defun* slurp-stream-forms (input &key count)
-"Read the contents of the INPUT stream as a list of forms,
+  (defun slurp-stream-forms (input &key count)
+    "Read the contents of the INPUT stream as a list of forms,
 and return those forms.
 
 If COUNT is null, read to the end of the stream;
 if COUNT is an integer, stop after COUNT forms were read.
 
 BEWARE: be sure to use WITH-SAFE-IO-SYNTAX, or some variant thereof"
-  (check-type count (or null integer))
-  (loop :with eof = '#:eof
-        :for n :from 0
-        :for form = (if (and count (>= n count))
-                        eof
-                        (read-preserving-whitespace input nil eof))
-        :until (eq form eof) :collect form))
+    (check-type count (or null integer))
+    (loop :with eof = '#:eof
+          :for n :from 0
+          :for form = (if (and count (>= n count))
+                          eof
+                          (read-preserving-whitespace input nil eof))
+          :until (eq form eof) :collect form))
 
-(defun* slurp-stream-form (input &key (at 0))
-"Read the contents of the INPUT stream as a list of forms,
+  (defun slurp-stream-form (input &key (at 0))
+    "Read the contents of the INPUT stream as a list of forms,
 then return the ACCESS-AT of these forms following the AT.
 AT defaults to 0, i.e. return the first form.
 AT is typically a list of integers.
@@ -2967,229 +3166,164 @@
 if path is either an integer or a list that starts with an integer.
 
 BEWARE: be sure to use WITH-SAFE-IO-SYNTAX, or some variant thereof"
-  (access-at (slurp-stream-forms input :count (access-at-count at)) at))
+    (access-at (slurp-stream-forms input :count (access-at-count at)) at))
 
-(defun* read-file-string (file &rest keys)
-  "Open FILE with option KEYS, read its contents as a string"
-  (apply 'call-with-input-file file 'slurp-stream-string keys))
+  (defun read-file-string (file &rest keys)
+    "Open FILE with option KEYS, read its contents as a string"
+    (apply 'call-with-input-file file 'slurp-stream-string keys))
 
-(defun* read-file-lines (file &rest keys)
-  "Open FILE with option KEYS, read its contents as a list of lines
+  (defun read-file-lines (file &rest keys)
+    "Open FILE with option KEYS, read its contents as a list of lines
 BEWARE: be sure to use WITH-SAFE-IO-SYNTAX, or some variant thereof"
-  (apply 'call-with-input-file file 'slurp-stream-lines keys))
+    (apply 'call-with-input-file file 'slurp-stream-lines keys))
 
-(defun* read-file-forms (file &rest keys &key count &allow-other-keys)
-  "Open input FILE with option KEYS (except COUNT),
+  (defun read-file-forms (file &rest keys &key count &allow-other-keys)
+    "Open input FILE with option KEYS (except COUNT),
 and read its contents as per SLURP-STREAM-FORMS with given COUNT.
 BEWARE: be sure to use WITH-SAFE-IO-SYNTAX, or some variant thereof"
-  (apply 'call-with-input-file file
-         #'(lambda (input) (slurp-stream-forms input :count count))
-         (remove-plist-key :count keys)))
+    (apply 'call-with-input-file file
+           #'(lambda (input) (slurp-stream-forms input :count count))
+           (remove-plist-key :count keys)))
 
-(defun* read-file-form (file &rest keys &key (at 0) &allow-other-keys)
-  "Open input FILE with option KEYS (except AT),
+  (defun read-file-form (file &rest keys &key (at 0) &allow-other-keys)
+    "Open input FILE with option KEYS (except AT),
 and read its contents as per SLURP-STREAM-FORM with given AT specifier.
 BEWARE: be sure to use WITH-SAFE-IO-SYNTAX, or some variant thereof"
-  (apply 'call-with-input-file file
-         #'(lambda (input) (slurp-stream-form input :at at))
-         (remove-plist-key :at keys)))
+    (apply 'call-with-input-file file
+           #'(lambda (input) (slurp-stream-form input :at at))
+           (remove-plist-key :at keys)))
 
-(defun* safe-read-file-form (pathname &rest keys &key (package :cl) &allow-other-keys)
-  "Reads the specified form from the top of a file using a safe standardized syntax.
+  (defun safe-read-file-form (pathname &rest keys &key (package :cl) &allow-other-keys)
+    "Reads the specified form from the top of a file using a safe standardized syntax.
 Extracts the form using READ-FILE-FORM,
 within an WITH-SAFE-IO-SYNTAX using the specified PACKAGE."
-  (with-safe-io-syntax (:package package)
-    (apply 'read-file-form pathname (remove-plist-key :package keys))))
+    (with-safe-io-syntax (:package package)
+      (apply 'read-file-form pathname (remove-plist-key :package keys))))
 
-(defun* eval-input (input)
-  "Portably read and evaluate forms from INPUT, return the last values."
-  (with-input (input)
-    (loop :with results :with eof ='#:eof
-          :for form = (read input nil eof)
-          :until (eq form eof)
-          :do (setf results (multiple-value-list (eval form)))
-          :finally (return (apply 'values results)))))
+  (defun eval-input (input)
+    "Portably read and evaluate forms from INPUT, return the last values."
+    (with-input (input)
+      (loop :with results :with eof ='#:eof
+            :for form = (read input nil eof)
+            :until (eq form eof)
+            :do (setf results (multiple-value-list (eval form)))
+            :finally (return (apply 'values results)))))
 
-(defun* eval-thunk (thunk)
-  "Evaluate a THUNK of code:
+  (defun eval-thunk (thunk)
+    "Evaluate a THUNK of code:
 If a function, FUNCALL it without arguments.
 If a constant literal and not a sequence, return it.
 If a cons or a symbol, EVAL it.
 If a string, repeatedly read and evaluate from it, returning the last values."
-  (etypecase thunk
-    ((or boolean keyword number character pathname) thunk)
-    ((or cons symbol) (eval thunk))
-    (function (funcall thunk))
-    (string (eval-input thunk))))
-
-(defun* standard-eval-thunk (thunk &key (package :cl))
-  "Like EVAL-THUNK, but in a more standardized evaluation context."
-  ;; Note: it's "standard-" not "safe-", because evaluation is never safe.
-  (when thunk
-    (with-safe-io-syntax (:package package)
-      (let ((*read-eval* t))
-        (eval-thunk thunk)))))
-
-
-;;; Encodings
-
-(defvar *default-encoding* :default
-  "Default encoding for source files.
-The default value :default preserves the legacy behavior.
-A future default might be :utf-8 or :autodetect
-reading emacs-style -*- coding: utf-8 -*- specifications,
-and falling back to utf-8 or latin1 if nothing is specified.")
-
-(defparameter *utf-8-external-format*
-  #+(and asdf-unicode (not clisp)) :utf-8
-  #+(and asdf-unicode clisp) charset:utf-8
-  #-asdf-unicode :default
-  "Default :external-format argument to pass to CL:OPEN and also
-CL:LOAD or CL:COMPILE-FILE to best process a UTF-8 encoded file.
-On modern implementations, this will decode UTF-8 code points as CL characters.
-On legacy implementations, it may fall back on some 8-bit encoding,
-with non-ASCII code points being read as several CL characters;
-hopefully, if done consistently, that won't affect program behavior too much.")
-
-(defun* always-default-encoding (pathname)
-  (declare (ignore pathname))
-  *default-encoding*)
-
-(defvar *encoding-detection-hook* #'always-default-encoding
-  "Hook for an extension to define a function to automatically detect a file's encoding")
-
-(defun* detect-encoding (pathname)
-  (if (and pathname (not (directory-pathname-p pathname)) (probe-file pathname))
-      (funcall *encoding-detection-hook* pathname)
-      *default-encoding*))
-
-(defun* default-encoding-external-format (encoding)
-  (case encoding
-    (:default :default) ;; for backward-compatibility only. Explicit usage discouraged.
-    (:utf-8 *utf-8-external-format*)
-    (otherwise
-     (cerror "Continue using :external-format :default" (compatfmt "~@<Your ASDF component is using encoding ~S but it isn't recognized. Your system should :defsystem-depends-on (:asdf-encodings).~:>") encoding)
-     :default)))
-
-(defvar *encoding-external-format-hook*
-  #'default-encoding-external-format
-  "Hook for an extension to define a mapping between non-default encodings
-and implementation-defined external-format's")
-
-(defun* encoding-external-format (encoding)
-  (funcall *encoding-external-format-hook* encoding))
-
-
-;;; Simple filesystem operations
-(defun* ensure-all-directories-exist (pathnames)
-   (dolist (pathname pathnames)
-     (ensure-directories-exist (translate-logical-pathname pathname))))
-
-(defun* rename-file-overwriting-target (source target)
-  #+clisp ;; But for a bug in CLISP 2.48, we should use :if-exists :overwrite and be atomic
-  (posix:copy-file source target :method :rename)
-  #-clisp
-  (rename-file source target
-               #+clozure :if-exists #+clozure :rename-and-delete))
-
-(defun* delete-file-if-exists (x)
-  (handler-case (delete-file x) (file-error () nil)))
+    (etypecase thunk
+      ((or boolean keyword number character pathname) thunk)
+      ((or cons symbol) (eval thunk))
+      (function (funcall thunk))
+      (string (eval-input thunk))))
+
+  (defun standard-eval-thunk (thunk &key (package :cl))
+    "Like EVAL-THUNK, but in a more standardized evaluation context."
+    ;; Note: it's "standard-" not "safe-", because evaluation is never safe.
+    (when thunk
+      (with-safe-io-syntax (:package package)
+        (let ((*read-eval* t))
+          (eval-thunk thunk))))))
 
 
 ;;; Using temporary files
-(defun* default-temporary-directory ()
-  (or
-   (when (os-unix-p)
-     (or (getenv-pathname "TMPDIR" :ensure-directory t)
-         (parse-native-namestring "/tmp/")))
-   (when (os-windows-p)
-     (getenv-pathname "TEMP" :ensure-directory t))
-   (subpathname (user-homedir-pathname) "tmp/")))
-
-(defvar *temporary-directory* nil)
-
-(defun* temporary-directory ()
-  (or *temporary-directory* (default-temporary-directory)))
-
-(defun setup-temporary-directory ()
-  (setf *temporary-directory* (default-temporary-directory))
-  ;; basic lack fixed after gcl 2.7.0-61, but ending / required still on 2.7.0-64.1
-  #+(and gcl (not gcl2.6)) (setf system::*tmp-dir* *temporary-directory*))
-
-(defun* call-with-temporary-file
-    (thunk &key
-     prefix keep (direction :io)
-     (element-type *default-stream-element-type*)
-     (external-format :default))
-  #+gcl2.6 (declare (ignorable external-format))
-  (check-type direction (member :output :io))
-  (loop
-    :with prefix = (or prefix (format nil "~Atmp" (native-namestring (temporary-directory))))
-    :for counter :from (random (ash 1 32))
-    :for pathname = (pathname (format nil "~A~36R" prefix counter)) :do
-     ;; TODO: on Unix, do something about umask
-     ;; TODO: on Unix, audit the code so we make sure it uses O_CREAT|O_EXCL
-     ;; TODO: on Unix, use CFFI and mkstemp -- but the master is precisely meant to not depend on CFFI or on anything! Grrrr.
-    (with-open-file (stream pathname
-                            :direction direction
-                            :element-type element-type
-                            #-gcl2.6 :external-format #-gcl2.6 external-format
-                            :if-exists nil :if-does-not-exist :create)
-      (when stream
-        (return
-          (if keep
-              (funcall thunk stream pathname)
-              (unwind-protect
-                   (funcall thunk stream pathname)
-                (ignore-errors (delete-file pathname)))))))))
-
-(defmacro with-temporary-file ((&key (stream (gensym "STREAM") streamp)
-                                (pathname (gensym "PATHNAME") pathnamep)
-                                prefix keep direction element-type external-format)
-                               &body body)
-  "Evaluate BODY where the symbols specified by keyword arguments
+(with-upgradability ()
+  (defun default-temporary-directory ()
+    (or
+     (when (os-unix-p)
+       (or (getenv-pathname "TMPDIR" :ensure-directory t)
+           (parse-native-namestring "/tmp/")))
+     (when (os-windows-p)
+       (getenv-pathname "TEMP" :ensure-directory t))
+     (subpathname (user-homedir-pathname) "tmp/")))
+
+  (defvar *temporary-directory* nil)
+
+  (defun temporary-directory ()
+    (or *temporary-directory* (default-temporary-directory)))
+
+  (defun setup-temporary-directory ()
+    (setf *temporary-directory* (default-temporary-directory))
+    ;; basic lack fixed after gcl 2.7.0-61, but ending / required still on 2.7.0-64.1
+    #+(and gcl (not gcl2.6)) (setf system::*tmp-dir* *temporary-directory*))
+
+  (defun call-with-temporary-file
+      (thunk &key
+               prefix keep (direction :io)
+               (element-type *default-stream-element-type*)
+               (external-format :default))
+    #+gcl2.6 (declare (ignorable external-format))
+    (check-type direction (member :output :io))
+    (loop
+      :with prefix = (or prefix (format nil "~Atmp" (native-namestring (temporary-directory))))
+      :for counter :from (random (ash 1 32))
+      :for pathname = (pathname (format nil "~A~36R" prefix counter)) :do
+        ;; TODO: on Unix, do something about umask
+        ;; TODO: on Unix, audit the code so we make sure it uses O_CREAT|O_EXCL
+        ;; TODO: on Unix, use CFFI and mkstemp -- but asdf/driver is precisely meant to not depend on CFFI or on anything! Grrrr.
+        (with-open-file (stream pathname
+                                :direction direction
+                                :element-type element-type
+                                #-gcl2.6 :external-format #-gcl2.6 external-format
+                                :if-exists nil :if-does-not-exist :create)
+          (when stream
+            (return
+              (if keep
+                  (funcall thunk stream pathname)
+                  (unwind-protect
+                       (funcall thunk stream pathname)
+                    (ignore-errors (delete-file pathname)))))))))
+
+  (defmacro with-temporary-file ((&key (stream (gensym "STREAM") streamp)
+                                    (pathname (gensym "PATHNAME") pathnamep)
+                                    prefix keep direction element-type external-format)
+                                 &body body)
+    "Evaluate BODY where the symbols specified by keyword arguments
 STREAM and PATHNAME are bound corresponding to a newly created temporary file
 ready for I/O. Unless KEEP is specified, delete the file afterwards."
-  (check-type stream symbol)
-  (check-type pathname symbol)
-  `(flet ((think (,stream ,pathname)
-            ,@(unless pathnamep `((declare (ignore ,pathname))))
-            ,@(unless streamp `((when ,stream (close ,stream))))
-            , at body))
-     #-gcl (declare (dynamic-extent #'think))
-     (call-with-temporary-file
-      #'think
-      ,@(when direction `(:direction ,direction))
-      ,@(when prefix `(:prefix ,prefix))
-      ,@(when keep `(:keep ,keep))
-      ,@(when element-type `(:element-type ,element-type))
-      ,@(when external-format `(:external-format external-format)))))
-
-;;; Temporary pathnames
-(defun* add-pathname-suffix (pathname suffix)
-  (make-pathname :name (strcat (pathname-name pathname) suffix)
-                 :defaults pathname))
+    (check-type stream symbol)
+    (check-type pathname symbol)
+    `(flet ((think (,stream ,pathname)
+              ,@(unless pathnamep `((declare (ignore ,pathname))))
+              ,@(unless streamp `((when ,stream (close ,stream))))
+              , at body))
+       #-gcl (declare (dynamic-extent #'think))
+       (call-with-temporary-file
+        #'think
+        ,@(when direction `(:direction ,direction))
+        ,@(when prefix `(:prefix ,prefix))
+        ,@(when keep `(:keep ,keep))
+        ,@(when element-type `(:element-type ,element-type))
+        ,@(when external-format `(:external-format external-format)))))
+
+  ;; Temporary pathnames in simple cases where no contention is assumed
+  (defun add-pathname-suffix (pathname suffix)
+    (make-pathname :name (strcat (pathname-name pathname) suffix)
+                   :defaults pathname))
 
-(defun* tmpize-pathname (x)
-  (add-pathname-suffix x "-ASDF-TMP"))
+  (defun tmpize-pathname (x)
+    (add-pathname-suffix x "-ASDF-TMP"))
 
-(defun* call-with-staging-pathname (pathname fun)
-  "Calls fun with a staging pathname, and atomically
+  (defun call-with-staging-pathname (pathname fun)
+    "Calls fun with a staging pathname, and atomically
 renames the staging pathname to the pathname in the end.
 Note: this protects only against failure of the program,
 not against concurrent attempts.
 For the latter case, we ought pick random suffix and atomically open it."
-  (let* ((pathname (pathname pathname))
-         (staging (tmpize-pathname pathname)))
-    (unwind-protect
-         (multiple-value-prog1
-             (funcall fun staging)
-           (rename-file-overwriting-target staging pathname))
-      (delete-file-if-exists staging))))
-
-(defmacro with-staging-pathname ((pathname-var &optional (pathname-value pathname-var)) &body body)
-  `(call-with-staging-pathname ,pathname-value #'(lambda (,pathname-var) , at body)))
+    (let* ((pathname (pathname pathname))
+           (staging (tmpize-pathname pathname)))
+      (unwind-protect
+           (multiple-value-prog1
+               (funcall fun staging)
+             (rename-file-overwriting-target staging pathname))
+        (delete-file-if-exists staging))))
 
+  (defmacro with-staging-pathname ((pathname-var &optional (pathname-value pathname-var)) &body body)
+    `(call-with-staging-pathname ,pathname-value #'(lambda (,pathname-var) , at body))))
 
 ;;;; -------------------------------------------------------------------------
 ;;;; Starting, Stopping, Dumping a Lisp image
@@ -3213,312 +3347,318 @@
 ))
 (in-package :asdf/image)
 
-(defvar *lisp-interaction* t
-  "Is this an interactive Lisp environment, or is it batch processing?")
+(with-upgradability ()
+  (defvar *lisp-interaction* t
+    "Is this an interactive Lisp environment, or is it batch processing?")
 
-(defvar *command-line-arguments* nil
-  "Command-line arguments")
+  (defvar *command-line-arguments* nil
+    "Command-line arguments")
 
-(defvar *image-dumped-p* nil ; may matter as to how to get to command-line-arguments
-  "Is this a dumped image? As a standalone executable?")
+  (defvar *image-dumped-p* nil ; may matter as to how to get to command-line-arguments
+    "Is this a dumped image? As a standalone executable?")
 
-(defvar *image-restore-hook* nil
-  "Functions to call (in reverse order) when the image is restored")
+  (defvar *image-restore-hook* nil
+    "Functions to call (in reverse order) when the image is restored")
 
-(defvar *image-prelude* nil
-  "a form to evaluate, or string containing forms to read and evaluate
+  (defvar *image-prelude* nil
+    "a form to evaluate, or string containing forms to read and evaluate
 when the image is restarted, but before the entry point is called.")
 
-(defvar *image-entry-point* nil
-  "a function with which to restart the dumped image when execution is restored from it.")
+  (defvar *image-entry-point* nil
+    "a function with which to restart the dumped image when execution is restored from it.")
 
-(defvar *image-postlude* nil
-  "a form to evaluate, or string containing forms to read and evaluate
+  (defvar *image-postlude* nil
+    "a form to evaluate, or string containing forms to read and evaluate
 before the image dump hooks are called and before the image is dumped.")
 
-(defvar *image-dump-hook* nil
-  "Functions to call (in order) when before an image is dumped")
+  (defvar *image-dump-hook* nil
+    "Functions to call (in order) when before an image is dumped")
 
-(defvar *fatal-conditions* '(error)
-  "conditions that cause the Lisp image to enter the debugger if interactive,
-or to die if not interactive")
+  (defvar *fatal-conditions* '(error)
+    "conditions that cause the Lisp image to enter the debugger if interactive,
+or to die if not interactive"))
 
 
 ;;; Exiting properly or im-
-(defun* quit (&optional (code 0) (finish-output t))
-  "Quits from the Lisp world, with the given exit status if provided.
+(with-upgradability ()
+  (defun quit (&optional (code 0) (finish-output t))
+    "Quits from the Lisp world, with the given exit status if provided.
 This is designed to abstract away the implementation specific quit forms."
-  (when finish-output ;; essential, for ClozureCL, and for standard compliance.
-    (finish-outputs))
-  #+(or abcl xcl) (ext:quit :status code)
-  #+allegro (excl:exit code :quiet t)
-  #+clisp (ext:quit code)
-  #+clozure (ccl:quit code)
-  #+cormanlisp (win32:exitprocess code)
-  #+(or cmu scl) (unix:unix-exit code)
-  #+ecl (si:quit code)
-  #+gcl (lisp:quit code)
-  #+genera (error "You probably don't want to Halt the Machine. (code: ~S)" code)
-  #+lispworks (lispworks:quit :status code :confirm nil :return nil :ignore-errors-p t)
-  #+mcl (ccl:quit) ;; or should we use FFI to call libc's exit(3) ?
-  #+mkcl (mk-ext:quit :exit-code code)
-  #+sbcl #.(let ((exit (find-symbol* :exit :sb-ext nil))
-		 (quit (find-symbol* :quit :sb-ext nil)))
-	     (cond
-	       (exit `(,exit :code code :abort (not finish-output)))
-	       (quit `(,quit :unix-status code :recklessly-p (not finish-output)))))
-  #-(or abcl allegro clisp clozure cmu ecl gcl genera lispworks mcl mkcl sbcl scl xcl)
-  (error "~S called with exit code ~S but there's no quitting on this implementation" 'quit code))
-
-(defun* die (code format &rest arguments)
-  "Die in error with some error message"
-  (with-safe-io-syntax ()
-    (ignore-errors
-     (fresh-line *stderr*)
-     (apply #'format *stderr* format arguments)
-     (format! *stderr* "~&")))
-  (quit code))
-
-(defun* raw-print-backtrace (&key (stream *debug-io*) count)
-  "Print a backtrace, directly accessing the implementation"
-  (declare (ignorable stream count))
-  #+allegro
-  (let ((*terminal-io* stream)
-        (*standard-output* stream)
-        (tpl:*zoom-print-circle* *print-circle*)
-        (tpl:*zoom-print-level* *print-level*)
-        (tpl:*zoom-print-length* *print-length*))
-    (tpl:do-command "zoom"
-      :from-read-eval-print-loop nil
-      :count t
-      :all t))
-  #+clisp
-  (system::print-backtrace :out stream :limit count)
-  #+(or clozure mcl)
-  (let ((*debug-io* stream))
-    (ccl:print-call-history :count count :start-frame-number 1)
-    (finish-output stream))
-  #+(or cmucl scl)
-  (let ((debug:*debug-print-level* *print-level*)
-        (debug:*debug-print-length* *print-length*))
-    (debug:backtrace most-positive-fixnum stream))
-  #+ecl
-  (si::tpl-backtrace)
-  #+lispworks
-  (let ((dbg::*debugger-stack*
-          (dbg::grab-stack nil :how-many (or count most-positive-fixnum)))
-        (*debug-io* stream)
-        (dbg:*debug-print-level* *print-level*)
-        (dbg:*debug-print-length* *print-length*))
-    (dbg:bug-backtrace nil))
-  #+sbcl
-  (sb-debug:backtrace
-   #.(if (find-symbol* "*VERBOSITY*" "SB-DEBUG" nil) :stream '(or count most-positive-fixnum))
-   stream))
-
-(defun* print-backtrace (&rest keys &key stream count)
-  (declare (ignore stream count))
-  (with-safe-io-syntax (:package :cl)
-    (let ((*print-readably* nil)
-          (*print-circle* t)
-          (*print-miser-width* 75)
-          (*print-length* nil)
-          (*print-level* nil)
-          (*print-pretty* t))
-      (ignore-errors (apply 'raw-print-backtrace keys)))))
-
-(defun* print-condition-backtrace (condition &key (stream *stderr*) count)
-  ;; We print the condition *after* the backtrace,
-  ;; for the sake of who sees the backtrace at a terminal.
-  ;; It is up to the caller to print the condition *before*, with some context.
-  (print-backtrace :stream stream :count count)
-  (when condition
-    (safe-format! stream "~&Above backtrace due to this condition:~%~A~&"
-                  condition)))
-
-(defun fatal-condition-p (condition)
-  (match-any-condition-p condition *fatal-conditions*))
+    (when finish-output ;; essential, for ClozureCL, and for standard compliance.
+      (finish-outputs))
+    #+(or abcl xcl) (ext:quit :status code)
+    #+allegro (excl:exit code :quiet t)
+    #+clisp (ext:quit code)
+    #+clozure (ccl:quit code)
+    #+cormanlisp (win32:exitprocess code)
+    #+(or cmu scl) (unix:unix-exit code)
+    #+ecl (si:quit code)
+    #+gcl (lisp:quit code)
+    #+genera (error "You probably don't want to Halt the Machine. (code: ~S)" code)
+    #+lispworks (lispworks:quit :status code :confirm nil :return nil :ignore-errors-p t)
+    #+mcl (ccl:quit) ;; or should we use FFI to call libc's exit(3) ?
+    #+mkcl (mk-ext:quit :exit-code code)
+    #+sbcl #.(let ((exit (find-symbol* :exit :sb-ext nil))
+                   (quit (find-symbol* :quit :sb-ext nil)))
+               (cond
+                 (exit `(,exit :code code :abort (not finish-output)))
+                 (quit `(,quit :unix-status code :recklessly-p (not finish-output)))))
+    #-(or abcl allegro clisp clozure cmu ecl gcl genera lispworks mcl mkcl sbcl scl xcl)
+    (error "~S called with exit code ~S but there's no quitting on this implementation" 'quit code))
 
-(defun* handle-fatal-condition (condition)
-  "Depending on whether *LISP-INTERACTION* is set, enter debugger or die"
-  (cond
-    (*lisp-interaction*
-     (invoke-debugger condition))
-    (t
-     (safe-format! *stderr* "~&Fatal condition:~%~A~%" condition)
-     (print-condition-backtrace condition :stream *stderr*)
-     (die 99 "~A" condition))))
-
-(defun* call-with-fatal-condition-handler (thunk)
-  (handler-bind (((satisfies fatal-condition-p) #'handle-fatal-condition))
-    (funcall thunk)))
-
-(defmacro with-fatal-condition-handler ((&optional) &body body)
-  `(call-with-fatal-condition-handler #'(lambda () , at body)))
-
-(defun* shell-boolean-exit (x)
-  "Quit with a return code that is 0 iff argument X is true"
-  (quit (if x 0 1)))
+  (defun die (code format &rest arguments)
+    "Die in error with some error message"
+    (with-safe-io-syntax ()
+      (ignore-errors
+       (fresh-line *stderr*)
+       (apply #'format *stderr* format arguments)
+       (format! *stderr* "~&")))
+    (quit code))
+
+  (defun raw-print-backtrace (&key (stream *debug-io*) count)
+    "Print a backtrace, directly accessing the implementation"
+    (declare (ignorable stream count))
+    #+abcl
+    (let ((*debug-io* stream)) (top-level::backtrace-command count))
+    #+allegro
+    (let ((*terminal-io* stream)
+          (*standard-output* stream)
+          (tpl:*zoom-print-circle* *print-circle*)
+          (tpl:*zoom-print-level* *print-level*)
+          (tpl:*zoom-print-length* *print-length*))
+      (tpl:do-command "zoom"
+        :from-read-eval-print-loop nil
+        :count t
+        :all t))
+    #+clisp
+    (system::print-backtrace :out stream :limit count)
+    #+(or clozure mcl)
+    (let ((*debug-io* stream))
+      (ccl:print-call-history :count count :start-frame-number 1)
+      (finish-output stream))
+    #+(or cmucl scl)
+    (let ((debug:*debug-print-level* *print-level*)
+          (debug:*debug-print-length* *print-length*))
+      (debug:backtrace most-positive-fixnum stream))
+    #+ecl
+    (si::tpl-backtrace)
+    #+lispworks
+    (let ((dbg::*debugger-stack*
+            (dbg::grab-stack nil :how-many (or count most-positive-fixnum)))
+          (*debug-io* stream)
+          (dbg:*debug-print-level* *print-level*)
+          (dbg:*debug-print-length* *print-length*))
+      (dbg:bug-backtrace nil))
+    #+sbcl
+    (sb-debug:backtrace
+     #.(if (find-symbol* "*VERBOSITY*" "SB-DEBUG" nil) :stream '(or count most-positive-fixnum))
+     stream))
+
+  (defun print-backtrace (&rest keys &key stream count)
+    (declare (ignore stream count))
+    (with-safe-io-syntax (:package :cl)
+      (let ((*print-readably* nil)
+            (*print-circle* t)
+            (*print-miser-width* 75)
+            (*print-length* nil)
+            (*print-level* nil)
+            (*print-pretty* t))
+        (ignore-errors (apply 'raw-print-backtrace keys)))))
+
+  (defun print-condition-backtrace (condition &key (stream *stderr*) count)
+    ;; We print the condition *after* the backtrace,
+    ;; for the sake of who sees the backtrace at a terminal.
+    ;; It is up to the caller to print the condition *before*, with some context.
+    (print-backtrace :stream stream :count count)
+    (when condition
+      (safe-format! stream "~&Above backtrace due to this condition:~%~A~&"
+                    condition)))
 
+  (defun fatal-condition-p (condition)
+    (match-any-condition-p condition *fatal-conditions*))
 
-;;; Using image hooks
+  (defun handle-fatal-condition (condition)
+    "Depending on whether *LISP-INTERACTION* is set, enter debugger or die"
+    (cond
+      (*lisp-interaction*
+       (invoke-debugger condition))
+      (t
+       (safe-format! *stderr* "~&Fatal condition:~%~A~%" condition)
+       (print-condition-backtrace condition :stream *stderr*)
+       (die 99 "~A" condition))))
 
-(defun* register-image-restore-hook (hook &optional (call-now-p t))
-  (register-hook-function '*image-restore-hook* hook call-now-p))
+  (defun call-with-fatal-condition-handler (thunk)
+    (handler-bind (((satisfies fatal-condition-p) #'handle-fatal-condition))
+      (funcall thunk)))
 
-(defun* register-image-dump-hook (hook &optional (call-now-p nil))
-  (register-hook-function '*image-dump-hook* hook call-now-p))
+  (defmacro with-fatal-condition-handler ((&optional) &body body)
+    `(call-with-fatal-condition-handler #'(lambda () , at body)))
 
-(defun* call-image-restore-hook ()
-  (call-functions (reverse *image-restore-hook*)))
+  (defun shell-boolean-exit (x)
+    "Quit with a return code that is 0 iff argument X is true"
+    (quit (if x 0 1))))
 
-(defun* call-image-dump-hook ()
-  (call-functions *image-dump-hook*))
 
+;;; Using image hooks
+(with-upgradability ()
+  (defun register-image-restore-hook (hook &optional (call-now-p t))
+    (register-hook-function '*image-restore-hook* hook call-now-p))
 
-;;; Proper command-line arguments
+  (defun register-image-dump-hook (hook &optional (call-now-p nil))
+    (register-hook-function '*image-dump-hook* hook call-now-p))
 
-(defun* raw-command-line-arguments ()
-  "Find what the actual command line for this process was."
-  #+abcl ext:*command-line-argument-list* ; Use 1.0.0 or later!
-  #+allegro (sys:command-line-arguments) ; default: :application t
-  #+clisp (coerce (ext:argv) 'list)
-  #+clozure (ccl::command-line-arguments)
-  #+(or cmu scl) extensions:*command-line-strings*
-  #+ecl (loop :for i :from 0 :below (si:argc) :collect (si:argv i))
-  #+gcl si:*command-args*
-  #+genera nil
-  #+lispworks sys:*line-arguments-list*
-  #+sbcl sb-ext:*posix-argv*
-  #+xcl system:*argv*
-  #-(or abcl allegro clisp clozure cmu ecl gcl genera lispworks sbcl scl xcl)
-  (error "raw-command-line-arguments not implemented yet"))
+  (defun call-image-restore-hook ()
+    (call-functions (reverse *image-restore-hook*)))
 
-(defun* command-line-arguments (&optional (arguments (raw-command-line-arguments)))
-  "Extract user arguments from command-line invocation of current process.
-Assume the calling conventions of a generated script that uses --
-if we are not called from a directly executable image."
-  #+abcl arguments
-  #-abcl
-  (let* (#-(or sbcl allegro)
-	 (arguments
-	  (if (eq *image-dumped-p* :executable)
-	      arguments
-	      (member "--" arguments :test 'string-equal))))
-    (rest arguments)))
-
-(defun setup-command-line-arguments ()
-  (setf *command-line-arguments* (command-line-arguments)))
-
-(defun* restore-image (&key
-                       ((:lisp-interaction *lisp-interaction*) *lisp-interaction*)
-                       ((:restore-hook *image-restore-hook*) *image-restore-hook*)
-                       ((:prelude *image-prelude*) *image-prelude*)
-                       ((:entry-point *image-entry-point*) *image-entry-point*))
-  (with-fatal-condition-handler ()
-    (call-image-restore-hook)
-    (standard-eval-thunk *image-prelude*)
-    (let ((results (multiple-value-list
-                    (if *image-entry-point*
-                        (call-function *image-entry-point*)
-                        t))))
-      (if *lisp-interaction*
-          (apply 'values results)
-          (shell-boolean-exit (first results))))))
+  (defun call-image-dump-hook ()
+    (call-functions *image-dump-hook*)))
 
 
-;;; Dumping an image
+;;; Proper command-line arguments
+(with-upgradability ()
+  (defun raw-command-line-arguments ()
+    "Find what the actual command line for this process was."
+    #+abcl ext:*command-line-argument-list* ; Use 1.0.0 or later!
+    #+allegro (sys:command-line-arguments) ; default: :application t
+    #+clisp (coerce (ext:argv) 'list)
+    #+clozure (ccl::command-line-arguments)
+    #+(or cmu scl) extensions:*command-line-strings*
+    #+ecl (loop :for i :from 0 :below (si:argc) :collect (si:argv i))
+    #+gcl si:*command-args*
+    #+genera nil
+    #+lispworks sys:*line-arguments-list*
+    #+sbcl sb-ext:*posix-argv*
+    #+xcl system:*argv*
+    #-(or abcl allegro clisp clozure cmu ecl gcl genera lispworks sbcl scl xcl)
+    (error "raw-command-line-arguments not implemented yet"))
 
-#-(or ecl mkcl)
-(defun* dump-image (filename &key output-name executable
-                             ((:postlude *image-postlude*) *image-postlude*)
-                             ((:dump-hook *image-dump-hook*) *image-dump-hook*))
-  (declare (ignorable filename output-name executable))
-  (setf *image-dumped-p* (if executable :executable t))
-  (standard-eval-thunk *image-postlude*)
-  (call-image-dump-hook)
-  #-(or clisp clozure cmu lispworks sbcl scl)
-  (when executable
-    (error "Dumping an executable is not supported on this implementation! Aborting."))
-  #+allegro
-  (progn
-    (sys:resize-areas :global-gc t :pack-heap t :sift-old-areas t :tenure t) ; :new 5000000
-    (excl:dumplisp :name filename :suppress-allegro-cl-banner t))
-  #+clisp
-  (apply #'ext:saveinitmem filename
-   :quiet t
-   :start-package *package*
-   :keep-global-handlers nil
-   :executable (if executable 0 t) ;--- requires clisp 2.48 or later, still catches --clisp-x
-   (when executable
-     (list
-      ;; :parse-options nil ;--- requires a non-standard patch to clisp.
-      :norc t :script nil :init-function #'restore-image)))
-  #+clozure
-  (ccl:save-application filename :prepend-kernel t
-                        :toplevel-function (when executable #'restore-image))
-  #+(or cmu scl)
-  (progn
-   (ext:gc :full t)
-   (setf ext:*batch-mode* nil)
-   (setf ext::*gc-run-time* 0)
-   (apply 'ext:save-lisp filename #+cmu :executable #+cmu t
-          (when executable '(:init-function restore-image :process-command-line nil))))
-  #+gcl
-  (progn
-   (si::set-hole-size 500) (si::gbc nil) (si::sgc-on t)
-   (si::save-system filename))
-  #+lispworks
-  (if executable
-      (lispworks:deliver 'restore-image filename 0 :interface nil)
-      (hcl:save-image filename :environment nil))
-  #+sbcl
-  (progn
-    ;;(sb-pcl::precompile-random-code-segments) ;--- it is ugly slow at compile-time (!) when the initial core is a big CLOS program. If you want it, do it yourself
-   (setf sb-ext::*gc-run-time* 0)
-   (apply 'sb-ext:save-lisp-and-die filename
-    :executable t ;--- always include the runtime that goes with the core
-    (when executable (list :toplevel #'restore-image :save-runtime-options t)))) ;--- only save runtime-options for standalone executables
-  #-(or allegro clisp clozure cmu gcl lispworks sbcl scl)
-  (die 98 "Can't dump ~S: asdf doesn't support image dumping with ~A.~%"
-       filename (nth-value 1 (implementation-type))))
+  (defun command-line-arguments (&optional (arguments (raw-command-line-arguments)))
+    "Extract user arguments from command-line invocation of current process.
+Assume the calling conventions of a generated script that uses --
+if we are not called from a directly executable image."
+    #+abcl arguments
+    #-abcl
+    (let* (#-(or sbcl allegro)
+           (arguments
+             (if (eq *image-dumped-p* :executable)
+                 arguments
+                 (member "--" arguments :test 'string-equal))))
+      (rest arguments)))
+
+  (defun setup-command-line-arguments ()
+    (setf *command-line-arguments* (command-line-arguments)))
+
+  (defun restore-image (&key
+                          ((:lisp-interaction *lisp-interaction*) *lisp-interaction*)
+                          ((:restore-hook *image-restore-hook*) *image-restore-hook*)
+                          ((:prelude *image-prelude*) *image-prelude*)
+                          ((:entry-point *image-entry-point*) *image-entry-point*))
+    (with-fatal-condition-handler ()
+      (call-image-restore-hook)
+      (standard-eval-thunk *image-prelude*)
+      (let ((results (multiple-value-list
+                      (if *image-entry-point*
+                          (call-function *image-entry-point*)
+                          t))))
+        (if *lisp-interaction*
+            (apply 'values results)
+            (shell-boolean-exit (first results)))))))
 
 
-#+ecl
-(defun create-image (destination object-files
-                     &key kind output-name prologue-code epilogue-code 
-                       (prelude () preludep) (entry-point () entry-point-p) build-args)
-  ;; Is it meaningful to run these in the current environment?
-  ;; only if we also track the object files that constitute the "current" image,
-  ;; and otherwise simulate dump-image, including quitting at the end.
-  ;; (standard-eval-thunk *image-postlude*) (call-image-dump-hook)
-  (check-type kind (member :binary :dll :lib :static-library :program :object :fasl :program))
-  (apply 'c::builder
-         kind (pathname destination)
-         :lisp-files object-files
-         :init-name (c::compute-init-name (or output-name destination) :kind kind)
-         :prologue-code prologue-code
-         :epilogue-code
-         `(progn
-            ,epilogue-code
-            ,@(when (eq kind :program)
-                `((setf *image-dumped-p* :executable)
-                  (restore-image ;; default behavior would be (si::top-level)
-                   ,@(when preludep `(:prelude ',prelude))
-                   ,@(when entry-point-p `(:entry-point ',entry-point))))))
-         build-args))
+;;; Dumping an image
+
+(with-upgradability ()
+  #-(or ecl mkcl)
+  (defun dump-image (filename &key output-name executable
+                                ((:postlude *image-postlude*) *image-postlude*)
+                                ((:dump-hook *image-dump-hook*) *image-dump-hook*))
+    (declare (ignorable filename output-name executable))
+    (setf *image-dumped-p* (if executable :executable t))
+    (standard-eval-thunk *image-postlude*)
+    (call-image-dump-hook)
+    #-(or clisp clozure cmu lispworks sbcl scl)
+    (when executable
+      (error "Dumping an executable is not supported on this implementation! Aborting."))
+    #+allegro
+    (progn
+      (sys:resize-areas :global-gc t :pack-heap t :sift-old-areas t :tenure t) ; :new 5000000
+      (excl:dumplisp :name filename :suppress-allegro-cl-banner t))
+    #+clisp
+    (apply #'ext:saveinitmem filename
+           :quiet t
+           :start-package *package*
+           :keep-global-handlers nil
+           :executable (if executable 0 t) ;--- requires clisp 2.48 or later, still catches --clisp-x
+           (when executable
+             (list
+              ;; :parse-options nil ;--- requires a non-standard patch to clisp.
+              :norc t :script nil :init-function #'restore-image)))
+    #+clozure
+    (ccl:save-application filename :prepend-kernel t
+                                   :toplevel-function (when executable #'restore-image))
+    #+(or cmu scl)
+    (progn
+      (ext:gc :full t)
+      (setf ext:*batch-mode* nil)
+      (setf ext::*gc-run-time* 0)
+      (apply 'ext:save-lisp filename #+cmu :executable #+cmu t
+                                     (when executable '(:init-function restore-image :process-command-line nil))))
+    #+gcl
+    (progn
+      (si::set-hole-size 500) (si::gbc nil) (si::sgc-on t)
+      (si::save-system filename))
+    #+lispworks
+    (if executable
+        (lispworks:deliver 'restore-image filename 0 :interface nil)
+        (hcl:save-image filename :environment nil))
+    #+sbcl
+    (progn
+      ;;(sb-pcl::precompile-random-code-segments) ;--- it is ugly slow at compile-time (!) when the initial core is a big CLOS program. If you want it, do it yourself
+      (setf sb-ext::*gc-run-time* 0)
+      (apply 'sb-ext:save-lisp-and-die filename
+             :executable t ;--- always include the runtime that goes with the core
+             (when executable (list :toplevel #'restore-image :save-runtime-options t)))) ;--- only save runtime-options for standalone executables
+    #-(or allegro clisp clozure cmu gcl lispworks sbcl scl)
+    (die 98 "Can't dump ~S: asdf doesn't support image dumping with ~A.~%"
+         filename (nth-value 1 (implementation-type))))
+
+
+  #+ecl
+  (defun create-image (destination object-files
+                       &key kind output-name prologue-code epilogue-code 
+                         (prelude () preludep) (entry-point () entry-point-p) build-args)
+    ;; Is it meaningful to run these in the current environment?
+    ;; only if we also track the object files that constitute the "current" image,
+    ;; and otherwise simulate dump-image, including quitting at the end.
+    ;; (standard-eval-thunk *image-postlude*) (call-image-dump-hook)
+    (check-type kind (member :binary :dll :lib :static-library :program :object :fasl :program))
+    (apply 'c::builder
+           kind (pathname destination)
+           :lisp-files object-files
+           :init-name (c::compute-init-name (or output-name destination) :kind kind)
+           :prologue-code prologue-code
+           :epilogue-code
+           `(progn
+              ,epilogue-code
+              ,@(when (eq kind :program)
+                  `((setf *image-dumped-p* :executable)
+                    (restore-image ;; default behavior would be (si::top-level)
+                     ,@(when preludep `(:prelude ',prelude))
+                     ,@(when entry-point-p `(:entry-point ',entry-point))))))
+           build-args)))
 
 
 ;;; Some universal image restore hooks
-(map () 'register-image-restore-hook
-     '(setup-temporary-directory setup-stderr setup-command-line-arguments
-       #+abcl detect-os))
+(with-upgradability ()
+  (map () 'register-image-restore-hook
+       '(setup-temporary-directory setup-stderr setup-command-line-arguments
+         #+abcl detect-os)))
 ;;;; -------------------------------------------------------------------------
 ;;;; run-program initially from xcvb-driver.
 
 (asdf/package:define-package :asdf/run-program
   (:recycle :asdf/run-program :xcvb-driver)
-  (:use :asdf/common-lisp :asdf/utility :asdf/pathname :asdf/stream :asdf/os)
+  (:use :asdf/common-lisp :asdf/utility :asdf/pathname :asdf/os :asdf/filesystem :asdf/stream)
   (:export
    ;;; Escaping the command invocation madness
    #:easy-sh-character-p #:escape-sh-token #:escape-sh-command
@@ -3535,196 +3675,197 @@
 
 ;;;; ----- Escaping strings for the shell -----
 
-(defun* requires-escaping-p (token &key good-chars bad-chars)
-  "Does this token require escaping, given the specification of
+(with-upgradability ()
+  (defun requires-escaping-p (token &key good-chars bad-chars)
+    "Does this token require escaping, given the specification of
 either good chars that don't need escaping or bad chars that do need escaping,
 as either a recognizing function or a sequence of characters."
-  (some
-   (cond
-     ((and good-chars bad-chars)
-      (error "only one of good-chars and bad-chars can be provided"))
-     ((functionp good-chars)
-      (complement good-chars))
-     ((functionp bad-chars)
-      bad-chars)
-     ((and good-chars (typep good-chars 'sequence))
-      #'(lambda (c) (not (find c good-chars))))
-     ((and bad-chars (typep bad-chars 'sequence))
-      #'(lambda (c) (find c bad-chars)))
-     (t (error "requires-escaping-p: no good-char criterion")))
-   token))
+    (some
+     (cond
+       ((and good-chars bad-chars)
+        (error "only one of good-chars and bad-chars can be provided"))
+       ((functionp good-chars)
+        (complement good-chars))
+       ((functionp bad-chars)
+        bad-chars)
+       ((and good-chars (typep good-chars 'sequence))
+        #'(lambda (c) (not (find c good-chars))))
+       ((and bad-chars (typep bad-chars 'sequence))
+        #'(lambda (c) (find c bad-chars)))
+       (t (error "requires-escaping-p: no good-char criterion")))
+     token))
 
-(defun* escape-token (token &key stream quote good-chars bad-chars escaper)
-  "Call the ESCAPER function on TOKEN string if it needs escaping as per
+  (defun escape-token (token &key stream quote good-chars bad-chars escaper)
+    "Call the ESCAPER function on TOKEN string if it needs escaping as per
 REQUIRES-ESCAPING-P using GOOD-CHARS and BAD-CHARS, otherwise output TOKEN,
 using STREAM as output (or returning result as a string if NIL)"
-  (if (requires-escaping-p token :good-chars good-chars :bad-chars bad-chars)
-      (with-output (stream)
-        (apply escaper token stream (when quote `(:quote ,quote))))
-      (output-string token stream)))
+    (if (requires-escaping-p token :good-chars good-chars :bad-chars bad-chars)
+        (with-output (stream)
+          (apply escaper token stream (when quote `(:quote ,quote))))
+        (output-string token stream)))
 
-(defun* escape-windows-token-within-double-quotes (x &optional s)
-  "Escape a string token X within double-quotes
+  (defun escape-windows-token-within-double-quotes (x &optional s)
+    "Escape a string token X within double-quotes
 for use within a MS Windows command-line, outputing to S."
-  (labels ((issue (c) (princ c s))
-           (issue-backslash (n) (loop :repeat n :do (issue #\\))))
-    (loop
-      :initially (issue #\") :finally (issue #\")
-      :with l = (length x) :with i = 0
-      :for i+1 = (1+ i) :while (< i l) :do
-      (case (char x i)
-        ((#\") (issue-backslash 1) (issue #\") (setf i i+1))
-        ((#\\)
-         (let* ((j (and (< i+1 l) (position-if-not
-                                   #'(lambda (c) (eql c #\\)) x :start i+1)))
-                (n (- (or j l) i)))
-           (cond
-             ((null j)
-              (issue-backslash (* 2 n)) (setf i l))
-             ((and (< j l) (eql (char x j) #\"))
-              (issue-backslash (1+ (* 2 n))) (issue #\") (setf i (1+ j)))
-             (t
-              (issue-backslash n) (setf i j)))))
-        (otherwise
-         (issue (char x i)) (setf i i+1))))))
+    (labels ((issue (c) (princ c s))
+             (issue-backslash (n) (loop :repeat n :do (issue #\\))))
+      (loop
+        :initially (issue #\") :finally (issue #\")
+        :with l = (length x) :with i = 0
+        :for i+1 = (1+ i) :while (< i l) :do
+          (case (char x i)
+            ((#\") (issue-backslash 1) (issue #\") (setf i i+1))
+            ((#\\)
+             (let* ((j (and (< i+1 l) (position-if-not
+                                       #'(lambda (c) (eql c #\\)) x :start i+1)))
+                    (n (- (or j l) i)))
+               (cond
+                 ((null j)
+                  (issue-backslash (* 2 n)) (setf i l))
+                 ((and (< j l) (eql (char x j) #\"))
+                  (issue-backslash (1+ (* 2 n))) (issue #\") (setf i (1+ j)))
+                 (t
+                  (issue-backslash n) (setf i j)))))
+            (otherwise
+             (issue (char x i)) (setf i i+1))))))
 
-(defun* escape-windows-token (token &optional s)
-  "Escape a string TOKEN within double-quotes if needed
+  (defun escape-windows-token (token &optional s)
+    "Escape a string TOKEN within double-quotes if needed
 for use within a MS Windows command-line, outputing to S."
-  (escape-token token :stream s :bad-chars #(#\space #\tab #\") :quote nil
-                :escaper 'escape-windows-token-within-double-quotes))
+    (escape-token token :stream s :bad-chars #(#\space #\tab #\") :quote nil
+                        :escaper 'escape-windows-token-within-double-quotes))
 
-(defun* escape-sh-token-within-double-quotes (x s &key (quote t))
-  "Escape a string TOKEN within double-quotes
+  (defun escape-sh-token-within-double-quotes (x s &key (quote t))
+    "Escape a string TOKEN within double-quotes
 for use within a POSIX Bourne shell, outputing to S;
 omit the outer double-quotes if key argument :QUOTE is NIL"
-  (when quote (princ #\" s))
-  (loop :for c :across x :do
-    (when (find c "$`\\\"") (princ #\\ s))
-    (princ c s))
-  (when quote (princ #\" s)))
+    (when quote (princ #\" s))
+    (loop :for c :across x :do
+      (when (find c "$`\\\"") (princ #\\ s))
+      (princ c s))
+    (when quote (princ #\" s)))
 
-(defun* easy-sh-character-p (x)
-  (or (alphanumericp x) (find x "+-_.,%@:/")))
+  (defun easy-sh-character-p (x)
+    (or (alphanumericp x) (find x "+-_.,%@:/")))
 
-(defun* escape-sh-token (token &optional s)
-  "Escape a string TOKEN within double-quotes if needed
+  (defun escape-sh-token (token &optional s)
+    "Escape a string TOKEN within double-quotes if needed
 for use within a POSIX Bourne shell, outputing to S."
-  (escape-token token :stream s :quote #\" :good-chars
-                #'easy-sh-character-p
-                :escaper 'escape-sh-token-within-double-quotes))
+    (escape-token token :stream s :quote #\" :good-chars
+                  #'easy-sh-character-p
+                        :escaper 'escape-sh-token-within-double-quotes))
 
-(defun* escape-shell-token (token &optional s)
-  (cond
-    ((os-unix-p) (escape-sh-token token s))
-    ((os-windows-p) (escape-windows-token token s))))
+  (defun escape-shell-token (token &optional s)
+    (cond
+      ((os-unix-p) (escape-sh-token token s))
+      ((os-windows-p) (escape-windows-token token s))))
 
-(defun* escape-command (command &optional s
-                       (escaper 'escape-shell-token))
-  "Given a COMMAND as a list of tokens, return a string of the
+  (defun escape-command (command &optional s
+                                  (escaper 'escape-shell-token))
+    "Given a COMMAND as a list of tokens, return a string of the
 spaced, escaped tokens, using ESCAPER to escape."
-  (etypecase command
-    (string (output-string command s))
-    (list (with-output (s)
-            (loop :for first = t :then nil :for token :in command :do
-              (unless first (princ #\space s))
-              (funcall escaper token s))))))
+    (etypecase command
+      (string (output-string command s))
+      (list (with-output (s)
+              (loop :for first = t :then nil :for token :in command :do
+                (unless first (princ #\space s))
+                (funcall escaper token s))))))
 
-(defun* escape-windows-command (command &optional s)
-  "Escape a list of command-line arguments into a string suitable for parsing
+  (defun escape-windows-command (command &optional s)
+    "Escape a list of command-line arguments into a string suitable for parsing
 by CommandLineToArgv in MS Windows"
     ;; http://msdn.microsoft.com/en-us/library/bb776391(v=vs.85).aspx
     ;; http://msdn.microsoft.com/en-us/library/17w5ykft(v=vs.85).aspx
-  (escape-command command s 'escape-windows-token))
+    (escape-command command s 'escape-windows-token))
 
-(defun* escape-sh-command (command &optional s)
-  "Escape a list of command-line arguments into a string suitable for parsing
+  (defun escape-sh-command (command &optional s)
+    "Escape a list of command-line arguments into a string suitable for parsing
 by /bin/sh in POSIX"
-  (escape-command command s 'escape-sh-token))
+    (escape-command command s 'escape-sh-token))
 
-(defun* escape-shell-command (command &optional stream)
-  "Escape a command for the current operating system's shell"
-  (escape-command command stream 'escape-shell-token))
+  (defun escape-shell-command (command &optional stream)
+    "Escape a command for the current operating system's shell"
+    (escape-command command stream 'escape-shell-token)))
 
 
 ;;;; Slurping a stream, typically the output of another program
-
-(defgeneric* slurp-input-stream (processor input-stream &key &allow-other-keys))
-
-#-(or gcl2.6 genera)
-(defmethod slurp-input-stream ((function function) input-stream &key &allow-other-keys)
-  (funcall function input-stream))
-
-(defmethod slurp-input-stream ((list cons) input-stream &key &allow-other-keys)
-  (apply (first list) (cons input-stream (rest list))))
-
-#-(or gcl2.6 genera)
-(defmethod slurp-input-stream ((output-stream stream) input-stream
-                               &key linewise prefix (element-type 'character) buffer-size &allow-other-keys)
-  (copy-stream-to-stream
-   input-stream output-stream
-   :linewise linewise :prefix prefix :element-type element-type :buffer-size buffer-size))
-
-(defmethod slurp-input-stream ((x (eql 'string)) stream &key &allow-other-keys)
-  (declare (ignorable x))
-  (slurp-stream-string stream))
-
-(defmethod slurp-input-stream ((x (eql :string)) stream &key &allow-other-keys)
-  (declare (ignorable x))
-  (slurp-stream-string stream))
-
-(defmethod slurp-input-stream ((x (eql :lines)) stream &key count &allow-other-keys)
-  (declare (ignorable x))
-  (slurp-stream-lines stream :count count))
-
-(defmethod slurp-input-stream ((x (eql :line)) stream &key (at 0) &allow-other-keys)
-  (declare (ignorable x))
-  (slurp-stream-line stream :at at))
-
-(defmethod slurp-input-stream ((x (eql :forms)) stream &key count &allow-other-keys)
-  (declare (ignorable x))
-  (slurp-stream-forms stream :count count))
-
-(defmethod slurp-input-stream ((x (eql :form)) stream &key (at 0) &allow-other-keys)
-  (declare (ignorable x))
-  (slurp-stream-form stream :at at))
-
-(defmethod slurp-input-stream (x stream
-                               &key linewise prefix (element-type 'character) buffer-size
-                               &allow-other-keys)
-  (declare (ignorable stream linewise prefix element-type buffer-size))
-  (cond
-    #+(or gcl2.6 genera)
-    ((functionp x) (funcall x stream))
-    #+(or gcl2.6 genera)
-    ((output-stream-p x)
-     (copy-stream-to-stream
-      input-stream output-stream
-      :linewise linewise :prefix prefix :element-type element-type :buffer-size buffer-size))
-    (t
-     (error "Invalid ~S destination ~S" 'slurp-input-stream x))))
+(with-upgradability ()
+  (defgeneric slurp-input-stream (processor input-stream &key &allow-other-keys))
+  
+  #-(or gcl2.6 genera)
+  (defmethod slurp-input-stream ((function function) input-stream &key &allow-other-keys)
+    (funcall function input-stream))
+
+  (defmethod slurp-input-stream ((list cons) input-stream &key &allow-other-keys)
+    (apply (first list) (cons input-stream (rest list))))
+
+  #-(or gcl2.6 genera)
+  (defmethod slurp-input-stream ((output-stream stream) input-stream
+                                 &key linewise prefix (element-type 'character) buffer-size &allow-other-keys)
+    (copy-stream-to-stream
+     input-stream output-stream
+     :linewise linewise :prefix prefix :element-type element-type :buffer-size buffer-size))
+
+  (defmethod slurp-input-stream ((x (eql 'string)) stream &key &allow-other-keys)
+    (declare (ignorable x))
+    (slurp-stream-string stream))
+
+  (defmethod slurp-input-stream ((x (eql :string)) stream &key &allow-other-keys)
+    (declare (ignorable x))
+    (slurp-stream-string stream))
+
+  (defmethod slurp-input-stream ((x (eql :lines)) stream &key count &allow-other-keys)
+    (declare (ignorable x))
+    (slurp-stream-lines stream :count count))
+
+  (defmethod slurp-input-stream ((x (eql :line)) stream &key (at 0) &allow-other-keys)
+    (declare (ignorable x))
+    (slurp-stream-line stream :at at))
+
+  (defmethod slurp-input-stream ((x (eql :forms)) stream &key count &allow-other-keys)
+    (declare (ignorable x))
+    (slurp-stream-forms stream :count count))
+
+  (defmethod slurp-input-stream ((x (eql :form)) stream &key (at 0) &allow-other-keys)
+    (declare (ignorable x))
+    (slurp-stream-form stream :at at))
+
+  (defmethod slurp-input-stream (x stream
+                                 &key linewise prefix (element-type 'character) buffer-size
+                                 &allow-other-keys)
+    (declare (ignorable stream linewise prefix element-type buffer-size))
+    (cond
+      #+(or gcl2.6 genera)
+      ((functionp x) (funcall x stream))
+      #+(or gcl2.6 genera)
+      ((output-stream-p x)
+       (copy-stream-to-stream
+        input-stream output-stream
+        :linewise linewise :prefix prefix :element-type element-type :buffer-size buffer-size))
+      (t
+       (error "Invalid ~S destination ~S" 'slurp-input-stream x)))))
 
 
 ;;;; ----- Running an external program -----
 ;;; Simple variant of run-program with no input, and capturing output
 ;;; On some implementations, may output to a temporary file...
-
-(define-condition subprocess-error (error)
-  ((code :initform nil :initarg :code :reader subprocess-error-code)
-   (command :initform nil :initarg :command :reader subprocess-error-command)
-   (process :initform nil :initarg :process :reader subprocess-error-process))
-  (:report (lambda (condition stream)
-             (format stream "Subprocess~@[ ~S~]~@[ run with command ~S~] exited with error~@[ code ~D~]"
-                     (subprocess-error-process condition)
-                     (subprocess-error-command condition)
-                     (subprocess-error-code condition)))))
-
-(defun* run-program (command
-                     &key output ignore-error-status force-shell
-                     (element-type *default-stream-element-type*)
-                     (external-format :default)
-                     &allow-other-keys)
-  "Run program specified by COMMAND,
+(with-upgradability ()
+  (define-condition subprocess-error (error)
+    ((code :initform nil :initarg :code :reader subprocess-error-code)
+     (command :initform nil :initarg :command :reader subprocess-error-command)
+     (process :initform nil :initarg :process :reader subprocess-error-process))
+    (:report (lambda (condition stream)
+               (format stream "Subprocess~@[ ~S~]~@[ run with command ~S~] exited with error~@[ code ~D~]"
+                       (subprocess-error-process condition)
+                       (subprocess-error-command condition)
+                       (subprocess-error-code condition)))))
+
+  (defun run-program (command
+                       &key output ignore-error-status force-shell
+                       (element-type *default-stream-element-type*)
+                       (external-format :default)
+                       &allow-other-keys)
+    "Run program specified by COMMAND,
 either a list of strings specifying a program and list of arguments,
 or a string specifying a shell command (/bin/sh on Unix, CMD.EXE on Windows);
 have its output processed by the OUTPUT processor function
@@ -3736,170 +3877,170 @@
 is specified.
 Return the exit status code of the process that was called.
 Use ELEMENT-TYPE and EXTERNAL-FORMAT for the stream passed to the OUTPUT processor."
-  (declare (ignorable ignore-error-status element-type external-format))
-  #-(or abcl allegro clisp clozure cmu cormanlisp ecl gcl lispworks mcl sbcl scl xcl)
-  (error "RUN-PROGRAM not implemented for this Lisp")
-  (labels (#+(or allegro clisp clozure cmu ecl (and lispworks os-unix) sbcl scl)
-           (run-program (command &key pipe interactive)
-             "runs the specified command (a list of program and arguments).
+    (declare (ignorable ignore-error-status element-type external-format))
+    #-(or abcl allegro clisp clozure cmu cormanlisp ecl gcl lispworks mcl sbcl scl xcl)
+    (error "RUN-PROGRAM not implemented for this Lisp")
+    (labels (#+(or allegro clisp clozure cmu ecl (and lispworks os-unix) sbcl scl)
+             (run-program (command &key pipe interactive)
+               "runs the specified command (a list of program and arguments).
               If using a pipe, returns two values: process and stream
               If not using a pipe, returns one values: the process result;
               also, inherits the output stream."
-             ;; NB: these implementations have unix vs windows set at compile-time.
-	     (assert (not (and pipe interactive)))
-             (let* ((wait (not pipe))
-                    #-(and clisp os-windows)
-                    (command
-                     (etypecase command
-                       #+os-unix (string `("/bin/sh" "-c" ,command))
-                       #+os-unix (list command)
-                       #+os-windows
-                       (string
-                        ;; NB: We do NOT add cmd /c here. You might want to.
-                        #+allegro command
-			;; On ClozureCL for Windows, we assume you are using
-			;; r15398 or later in 1.9 or later,
-			;; so that bug 858 is fixed http://trac.clozure.com/ccl/ticket/858
-			#+clozure (cons "cmd" (strcat "/c " command))
-                        ;; NB: On other Windows implementations, this is utterly bogus
-                        ;; except in the most trivial cases where no quoting is needed.
-                        ;; Use at your own risk.
-                        #-(or allegro clozure) (list "cmd" "/c" command))
-                       #+os-windows
-                       (list
-                        #+(or allegro clozure) (escape-windows-command command)
-                        #-(or allegro clozure) command)))
-                    #+(and clozure os-windows) (command (list command))
-                    (process*
-                     (multiple-value-list
-                      #+allegro
-                      (excl:run-shell-command
-                       #+os-unix (coerce (cons (first command) command) 'vector)
-                       #+os-windows command
-                       :input interactive :output (or (and pipe :stream) interactive) :wait wait
-                       #+os-windows :show-window #+os-windows (and pipe :hide))
-                      #+clisp
-                      (flet ((run (f &rest args)
-                               (apply f `(, at args :input ,(when interactive :terminal) :wait ,wait :output
-                                          ,(if pipe :stream :terminal)))))
+               ;; NB: these implementations have unix vs windows set at compile-time.
+               (assert (not (and pipe interactive)))
+               (let* ((wait (not pipe))
+                      #-(and clisp os-windows)
+                      (command
                         (etypecase command
-                          #+os-windows (run 'ext:run-shell-command command)
-                          (list (run 'ext:run-program (car command)
-                                     :arguments (cdr command)))))
-                      #+lispworks
-                      (system:run-shell-command
-                       (cons "/usr/bin/env" command) ; lispworks wants a full path.
-                       :input interactive :output (or (and pipe :stream) interactive)
-                       :wait wait :save-exit-status (and pipe t))
-                      #+(or clozure cmu ecl sbcl scl)
-                      (#+(or cmu ecl scl) ext:run-program
-                       #+clozure ccl:run-program
-                       #+sbcl sb-ext:run-program
-                       (car command) (cdr command)
-                       :input interactive :wait wait
-                       :output (if pipe :stream t)
-                       . #.(append
-                            #+(or clozure cmu ecl sbcl scl) '(:error t)
-                            ;; note: :external-format requires a recent SBCL
-                            #+sbcl '(:search t :external-format external-format)))))
-                    (process
-                     #+(or allegro lispworks) (if pipe (third process*) (first process*))
-                     #+ecl (third process*)
-                     #-(or allegro lispworks ecl) (first process*))
-                    (stream
-                     (when pipe
-                       #+(or allegro lispworks ecl) (first process*)
-                       #+clisp (first process*)
-                       #+clozure (ccl::external-process-output process)
-                       #+(or cmu scl) (ext:process-output process)
-                       #+sbcl (sb-ext:process-output process))))
-               (values process stream)))
-           #+(or allegro clisp clozure cmu ecl (and lispworks os-unix) sbcl scl)
-           (process-result (process pipe)
-             (declare (ignorable pipe))
-             ;; 1- wait
-             #+(and clozure os-unix) (ccl::external-process-wait process)
-             #+(or cmu scl) (ext:process-wait process)
-             #+(and ecl os-unix) (ext:external-process-wait process)
-             #+sbcl (sb-ext:process-wait process)
-             ;; 2- extract result
-             #+allegro (if pipe (sys:reap-os-subprocess :pid process :wait t) process)
-             #+clisp process
-             #+clozure (nth-value 1 (ccl:external-process-status process))
-             #+(or cmu scl) (ext:process-exit-code process)
-             #+ecl (nth-value 1 (ext:external-process-status process))
-             #+lispworks (if pipe (system:pid-exit-status process :wait t) process)
-             #+sbcl (sb-ext:process-exit-code process))
-           (check-result (exit-code process)
-             #+clisp
-             (setf exit-code
-                   (typecase exit-code (integer exit-code) (null 0) (t -1)))
-             (unless (or ignore-error-status
-                         (equal exit-code 0))
-               (error 'subprocess-error :command command :code exit-code :process process))
-	     exit-code)
-           (use-run-program ()
-             #-(or abcl cormanlisp gcl (and lispworks os-windows) mcl mkcl xcl)
-             (let* ((interactive (eq output :interactive))
-		    (pipe (and output (not interactive))))
-               (multiple-value-bind (process stream)
-                   (run-program command :pipe pipe :interactive interactive)
+                          #+os-unix (string `("/bin/sh" "-c" ,command))
+                          #+os-unix (list command)
+                          #+os-windows
+                          (string
+                           ;; NB: We do NOT add cmd /c here. You might want to.
+                           #+allegro command
+                           ;; On ClozureCL for Windows, we assume you are using
+                           ;; r15398 or later in 1.9 or later,
+                           ;; so that bug 858 is fixed http://trac.clozure.com/ccl/ticket/858
+                           #+clozure (cons "cmd" (strcat "/c " command))
+                           ;; NB: On other Windows implementations, this is utterly bogus
+                           ;; except in the most trivial cases where no quoting is needed.
+                           ;; Use at your own risk.
+                           #-(or allegro clozure) (list "cmd" "/c" command))
+                          #+os-windows
+                          (list
+                           #+(or allegro clozure) (escape-windows-command command)
+                           #-(or allegro clozure) command)))
+                      #+(and clozure os-windows) (command (list command))
+                      (process*
+                        (multiple-value-list
+                         #+allegro
+                         (excl:run-shell-command
+                          #+os-unix (coerce (cons (first command) command) 'vector)
+                          #+os-windows command
+                          :input interactive :output (or (and pipe :stream) interactive) :wait wait
+                          #+os-windows :show-window #+os-windows (and pipe :hide))
+                         #+clisp
+                         (flet ((run (f &rest args)
+                                  (apply f `(, at args :input ,(when interactive :terminal) :wait ,wait :output
+                                                    ,(if pipe :stream :terminal)))))
+                           (etypecase command
+                             #+os-windows (run 'ext:run-shell-command command)
+                             (list (run 'ext:run-program (car command)
+                                        :arguments (cdr command)))))
+                         #+lispworks
+                         (system:run-shell-command
+                          (cons "/usr/bin/env" command) ; lispworks wants a full path.
+                          :input interactive :output (or (and pipe :stream) interactive)
+                          :wait wait :save-exit-status (and pipe t))
+                         #+(or clozure cmu ecl sbcl scl)
+                         (#+(or cmu ecl scl) ext:run-program
+                            #+clozure ccl:run-program
+                            #+sbcl sb-ext:run-program
+                            (car command) (cdr command)
+                            :input interactive :wait wait
+                            :output (if pipe :stream t)
+                            . #.(append
+                                 #+(or clozure cmu ecl sbcl scl) '(:error t)
+                                 ;; note: :external-format requires a recent SBCL
+                                 #+sbcl '(:search t :external-format external-format)))))
+                      (process
+                        #+(or allegro lispworks) (if pipe (third process*) (first process*))
+                        #+ecl (third process*)
+                        #-(or allegro lispworks ecl) (first process*))
+                      (stream
+                        (when pipe
+                          #+(or allegro lispworks ecl) (first process*)
+                          #+clisp (first process*)
+                          #+clozure (ccl::external-process-output process)
+                          #+(or cmu scl) (ext:process-output process)
+                          #+sbcl (sb-ext:process-output process))))
+                 (values process stream)))
+             #+(or allegro clisp clozure cmu ecl (and lispworks os-unix) sbcl scl)
+             (process-result (process pipe)
+               (declare (ignorable pipe))
+               ;; 1- wait
+               #+(and clozure os-unix) (ccl::external-process-wait process)
+               #+(or cmu scl) (ext:process-wait process)
+               #+(and ecl os-unix) (ext:external-process-wait process)
+               #+sbcl (sb-ext:process-wait process)
+               ;; 2- extract result
+               #+allegro (if pipe (sys:reap-os-subprocess :pid process :wait t) process)
+               #+clisp process
+               #+clozure (nth-value 1 (ccl:external-process-status process))
+               #+(or cmu scl) (ext:process-exit-code process)
+               #+ecl (nth-value 1 (ext:external-process-status process))
+               #+lispworks (if pipe (system:pid-exit-status process :wait t) process)
+               #+sbcl (sb-ext:process-exit-code process))
+             (check-result (exit-code process)
+               #+clisp
+               (setf exit-code
+                     (typecase exit-code (integer exit-code) (null 0) (t -1)))
+               (unless (or ignore-error-status
+                           (equal exit-code 0))
+                 (error 'subprocess-error :command command :code exit-code :process process))
+               exit-code)
+             (use-run-program ()
+               #-(or abcl cormanlisp gcl (and lispworks os-windows) mcl mkcl xcl)
+               (let* ((interactive (eq output :interactive))
+                      (pipe (and output (not interactive))))
+                 (multiple-value-bind (process stream)
+                     (run-program command :pipe pipe :interactive interactive)
+                   (if (and output (not interactive))
+                       (unwind-protect
+                            (slurp-input-stream output stream)
+                         (when stream (close stream))
+                         (check-result (process-result process pipe) process))
+                       (unwind-protect
+                            (check-result
+                             #+(or allegro lispworks) ; when not capturing, returns the exit code!
+                             process
+                             #-(or allegro lispworks) (process-result process pipe)
+                             process))))))
+             (system-command (command)
+               (etypecase command
+                 (string (if (os-windows-p) (format nil "cmd /c ~A" command) command))
+                 (list (escape-shell-command
+                        (if (os-unix-p) (cons "exec" command) command)))))
+             (redirected-system-command (command out)
+               (format nil (if (os-unix-p) "exec > ~*~A ; ~2:*~A" "~A > ~A")
+                       (system-command command) (native-namestring out)))
+             (system (command &key interactive)
+               (declare (ignorable interactive))
+               #+(or abcl xcl) (ext:run-shell-command command)
+               #+allegro
+               (excl:run-shell-command command :input interactive :output interactive :wait t)
+               #+(or clisp clozure cmu (and lispworks os-unix) sbcl scl)
+               (process-result (run-program command :pipe nil :interactive interactive) nil)
+               #+ecl (ext:system command)
+               #+cormanlisp (win32:system command)
+               #+gcl (lisp:system command)
+               #+(and lispworks os-windows)
+               (system:call-system-showing-output
+                command :show-cmd interactive :prefix "" :output-stream nil)
+               #+mcl (ccl::with-cstrs ((%command command)) (_system %command))
+               #+mkcl (nth-value 2
+                                 (mkcl:run-program #+windows command #+windows ()
+                                                   #-windows "/bin/sh" (list "-c" command)
+                                                   :input nil :output nil)))
+             (call-system (command-string &key interactive)
+               (check-result (system command-string :interactive interactive) nil))
+             (use-system ()
+               (let ((interactive (eq output :interactive)))
                  (if (and output (not interactive))
-                     (unwind-protect
-                          (slurp-input-stream output stream)
-                       (when stream (close stream))
-                       (check-result (process-result process pipe) process))
-                     (unwind-protect
-                          (check-result
-                           #+(or allegro lispworks) ; when not capturing, returns the exit code!
-                           process
-                           #-(or allegro lispworks) (process-result process pipe)
-                           process))))))
-           (system-command (command)
-             (etypecase command
-               (string (if (os-windows-p) (format nil "cmd /c ~A" command) command))
-               (list (escape-shell-command
-                      (if (os-unix-p) (cons "exec" command) command)))))
-           (redirected-system-command (command out)
-             (format nil (if (os-unix-p) "exec > ~*~A ; ~2:*~A" "~A > ~A")
-                     (system-command command) (native-namestring out)))
-           (system (command &key interactive)
-             (declare (ignorable interactive))
-             #+(or abcl xcl) (ext:run-shell-command command)
-             #+allegro
-             (excl:run-shell-command command :input interactive :output interactive :wait t)
-             #+(or clisp clozure cmu (and lispworks os-unix) sbcl scl)
-             (process-result (run-program command :pipe nil :interactive interactive) nil)
-             #+ecl (ext:system command)
-             #+cormanlisp (win32:system command)
-             #+gcl (lisp:system command)
-             #+(and lispworks os-windows)
-             (system:call-system-showing-output
-              command :show-cmd interactive :prefix "" :output-stream nil)
-             #+mcl (ccl::with-cstrs ((%command command)) (_system %command))
-             #+mkcl (nth-value 2
-                               (mkcl:run-program #+windows command #+windows ()
-                                                 #-windows "/bin/sh" (list "-c" command)
-                                                 :input nil :output nil)))
-           (call-system (command-string &key interactive)
-             (check-result (system command-string :interactive interactive) nil))
-           (use-system ()
-	     (let ((interactive (eq output :interactive)))
-	       (if (and output (not interactive))
-		   (with-temporary-file (:pathname tmp :direction :output)
-		     (call-system (redirected-system-command command tmp))
-		     (with-open-file (stream tmp
-					     :direction :input
-					     :if-does-not-exist :error
-					     :element-type element-type
-                                             #-gcl2.6 :external-format #-gcl2.6 external-format)
-		       (slurp-input-stream output stream)))
-		   (call-system (system-command command) :interactive interactive)))))
-    (if (and (not force-shell)
-             #+(or clisp ecl) ignore-error-status
-             #+(or abcl cormanlisp gcl (and lispworks os-windows) mcl mkcl xcl) nil)
-        (use-run-program)
-        (use-system))))
+                     (with-temporary-file (:pathname tmp :direction :output)
+                       (call-system (redirected-system-command command tmp))
+                       (with-open-file (stream tmp
+                                               :direction :input
+                                               :if-does-not-exist :error
+                                               :element-type element-type
+                                               #-gcl2.6 :external-format #-gcl2.6 external-format)
+                         (slurp-input-stream output stream)))
+                     (call-system (system-command command) :interactive interactive)))))
+      (if (and (not force-shell)
+               #+(or clisp ecl) ignore-error-status
+               #+(or abcl cormanlisp gcl (and lispworks os-windows) mcl mkcl xcl) nil)
+          (use-run-program)
+          (use-system)))))
 
 ;;;; -------------------------------------------------------------------------
 ;;;; Support to build (compile and load) Lisp files
@@ -3907,7 +4048,7 @@
 (asdf/package:define-package :asdf/lisp-build
   (:recycle :asdf/interface :asdf :asdf/lisp-build)
   (:use :asdf/common-lisp :asdf/package :asdf/utility
-        :asdf/pathname :asdf/stream :asdf/os :asdf/image)
+   :asdf/os :asdf/pathname :asdf/filesystem :asdf/stream :asdf/image)
   (:export
    ;; Variables
    #:*compile-file-warnings-behaviour* #:*compile-file-failure-behaviour*
@@ -3925,7 +4066,6 @@
    #:reify-deferred-warnings #:reify-undefined-warning #:unreify-deferred-warnings
    #:reset-deferred-warnings #:save-deferred-warnings #:check-deferred-warnings
    #:with-saved-deferred-warnings #:warnings-file-p #:warnings-file-type #:*warnings-file-type*
-   #:call-with-asdf-compilation-unit #:with-asdf-compilation-unit
    #:current-lisp-file-pathname #:load-pathname
    #:lispize-pathname #:compile-file-type #:call-around-hook
    #:compile-file* #:compile-file-pathname*
@@ -3933,423 +4073,519 @@
   (:intern #:defaults #:failure-p #:warnings-p #:s #:y #:body))
 (in-package :asdf/lisp-build)
 
-(defvar *compile-file-warnings-behaviour*
-  (or #+clisp :ignore :warn)
-  "How should ASDF react if it encounters a warning when compiling a file?
+(with-upgradability ()
+  (defvar *compile-file-warnings-behaviour*
+    (or #+clisp :ignore :warn)
+    "How should ASDF react if it encounters a warning when compiling a file?
 Valid values are :error, :warn, and :ignore.")
 
-(defvar *compile-file-failure-behaviour*
-  (or #+(or mkcl sbcl) :error #+clisp :ignore :warn)
-  "How should ASDF react if it encounters a failure (per the ANSI spec of COMPILE-FILE)
+  (defvar *compile-file-failure-behaviour*
+    (or #+(or mkcl sbcl) :error #+clisp :ignore :warn)
+    "How should ASDF react if it encounters a failure (per the ANSI spec of COMPILE-FILE)
 when compiling a file, which includes any non-style-warning warning.
 Valid values are :error, :warn, and :ignore.
-Note that ASDF ALWAYS raises an error if it fails to create an output file when compiling.")
+Note that ASDF ALWAYS raises an error if it fails to create an output file when compiling."))
 
 
 ;;; Optimization settings
-
-(defvar *optimization-settings* nil)
-(defvar *previous-optimization-settings* nil)
-(defun* get-optimization-settings ()
-  "Get current compiler optimization settings, ready to PROCLAIM again"
-  (let ((settings '(speed space safety debug compilation-speed #+(or cmu scl) c::brevity)))
-    #-(or clisp clozure cmu ecl sbcl scl)
-    (warn "xcvb-driver::get-optimization-settings does not support your implementation. Please help me fix that.")
-    #.`(loop :for x :in settings
-         ,@(or #+clozure '(:for v :in '(ccl::*nx-speed* ccl::*nx-space* ccl::*nx-safety* ccl::*nx-debug* ccl::*nx-cspeed*))
-               #+ecl '(:for v :in '(c::*speed* c::*space* c::*safety* c::*debug*))
-               #+(or cmu scl) '(:for f :in '(c::cookie-speed c::cookie-space c::cookie-safety c::cookie-debug c::cookie-cspeed c::cookie-brevity)))
-         :for y = (or #+clisp (gethash x system::*optimize*)
-                      #+(or clozure ecl) (symbol-value v)
-                      #+(or cmu scl) (funcall f c::*default-cookie*)
-                      #+sbcl (cdr (assoc x sb-c::*policy*)))
-         :when y :collect (list x y))))
-(defun* proclaim-optimization-settings ()
-  "Proclaim the optimization settings in *OPTIMIZATION-SETTINGS*"
-  (proclaim `(optimize ,@*optimization-settings*))
-  (let ((settings (get-optimization-settings)))
-    (unless (equal *previous-optimization-settings* settings)
-      (setf *previous-optimization-settings* settings))))
+(with-upgradability ()
+  (defvar *optimization-settings* nil)
+  (defvar *previous-optimization-settings* nil)
+  (defun get-optimization-settings ()
+    "Get current compiler optimization settings, ready to PROCLAIM again"
+    (let ((settings '(speed space safety debug compilation-speed #+(or cmu scl) c::brevity)))
+      #-(or clisp clozure cmu ecl sbcl scl)
+      (warn "xcvb-driver::get-optimization-settings does not support your implementation. Please help me fix that.")
+      #.`(loop :for x :in settings
+               ,@(or #+clozure '(:for v :in '(ccl::*nx-speed* ccl::*nx-space* ccl::*nx-safety* ccl::*nx-debug* ccl::*nx-cspeed*))
+                     #+ecl '(:for v :in '(c::*speed* c::*space* c::*safety* c::*debug*))
+                     #+(or cmu scl) '(:for f :in '(c::cookie-speed c::cookie-space c::cookie-safety c::cookie-debug c::cookie-cspeed c::cookie-brevity)))
+               :for y = (or #+clisp (gethash x system::*optimize*)
+                            #+(or clozure ecl) (symbol-value v)
+                            #+(or cmu scl) (funcall f c::*default-cookie*)
+                            #+sbcl (cdr (assoc x sb-c::*policy*)))
+               :when y :collect (list x y))))
+  (defun proclaim-optimization-settings ()
+    "Proclaim the optimization settings in *OPTIMIZATION-SETTINGS*"
+    (proclaim `(optimize ,@*optimization-settings*))
+    (let ((settings (get-optimization-settings)))
+      (unless (equal *previous-optimization-settings* settings)
+        (setf *previous-optimization-settings* settings)))))
 
 
 ;;; Condition control
-
-#+sbcl
-(progn
-  (defun sb-grovel-unknown-constant-condition-p (c)
-    (and (typep c 'sb-int:simple-style-warning)
-         (string-enclosed-p
-          "Couldn't grovel for "
-          (simple-condition-format-control c)
-          " (unknown to the C compiler).")))
-  (deftype sb-grovel-unknown-constant-condition ()
-    '(and style-warning (satisfies sb-grovel-unknown-constant-condition-p))))
-
-(defvar *uninteresting-compiler-conditions*
-  (append
-   #+sbcl
-   `(sb-c::simple-compiler-note
-     "&OPTIONAL and &KEY found in the same lambda list: ~S"
-     sb-int:package-at-variance
-     sb-kernel:uninteresting-redefinition
-     sb-kernel:undefined-alien-style-warning
-     ;; sb-ext:implicit-generic-function-warning ; controversial, but let's allow it by default.
-     sb-kernel:lexical-environment-too-complex
-     sb-grovel-unknown-constant-condition ; defined above.
-     ;; BEWARE: the below four are controversial to include here.
-     sb-kernel:redefinition-with-defun
-     sb-kernel:redefinition-with-defgeneric
-     sb-kernel:redefinition-with-defmethod
-     sb-kernel::redefinition-with-defmacro) ; not exported by old SBCLs
-   ;;#+clozure '(ccl:compiler-warning)
-   '("No generic function ~S present when encountering macroexpansion of defmethod. Assuming it will be an instance of standard-generic-function.")) ;; from closer2mop
-  "Conditions that may be skipped while compiling")
-
-(defvar *uninteresting-loader-conditions*
-  (append
-   '("Overwriting already existing readtable ~S." ;; from named-readtables
-     #(#:finalizers-off-warning :asdf-finalizers)) ;; from asdf-finalizers
-   #+clisp '(clos::simple-gf-replacing-method-warning))
-  "Additional conditions that may be skipped while loading")
+(with-upgradability ()
+  #+sbcl
+  (progn
+    (defun sb-grovel-unknown-constant-condition-p (c)
+      (and (typep c 'sb-int:simple-style-warning)
+           (string-enclosed-p
+            "Couldn't grovel for "
+            (simple-condition-format-control c)
+            " (unknown to the C compiler).")))
+    (deftype sb-grovel-unknown-constant-condition ()
+      '(and style-warning (satisfies sb-grovel-unknown-constant-condition-p))))
+
+  (defvar *uninteresting-compiler-conditions*
+    (append
+     ;;#+clozure '(ccl:compiler-warning)
+     #+cmu '("Deleting unreachable code.")
+     #+lispworks '("~S being redefined in ~A (previously in ~A)."
+                   "~S defined more than once in ~A.") ;; lispworks gets confused by eval-when.
+     #+sbcl
+     '(sb-c::simple-compiler-note
+       "&OPTIONAL and &KEY found in the same lambda list: ~S"
+       sb-int:package-at-variance
+       sb-kernel:uninteresting-redefinition
+       sb-kernel:undefined-alien-style-warning
+       ;; sb-ext:implicit-generic-function-warning ; Controversial. Let's allow it by default.
+       #+sb-eval sb-kernel:lexical-environment-too-complex
+       sb-grovel-unknown-constant-condition ; defined above.
+       ;; BEWARE: the below four are controversial to include here.
+       sb-kernel:redefinition-with-defun
+       sb-kernel:redefinition-with-defgeneric
+       sb-kernel:redefinition-with-defmethod
+       sb-kernel::redefinition-with-defmacro) ; not exported by old SBCLs
+     '("No generic function ~S present when encountering macroexpansion of defmethod. Assuming it will be an instance of standard-generic-function.")) ;; from closer2mop
+    "Conditions that may be skipped while compiling")
+
+  (defvar *uninteresting-loader-conditions*
+    (append
+     '("Overwriting already existing readtable ~S." ;; from named-readtables
+       #(#:finalizers-off-warning :asdf-finalizers)) ;; from asdf-finalizers
+     #+clisp '(clos::simple-gf-replacing-method-warning))
+    "Additional conditions that may be skipped while loading"))
 
 ;;;; ----- Filtering conditions while building -----
-
-(defun* call-with-muffled-compiler-conditions (thunk)
-  (call-with-muffled-conditions
-    thunk *uninteresting-compiler-conditions*))
-(defmacro with-muffled-compiler-conditions ((&optional) &body body)
-  "Run BODY where uninteresting compiler conditions are muffled"
-  `(call-with-muffled-compiler-conditions #'(lambda () , at body)))
-(defun* call-with-muffled-loader-conditions (thunk)
-  (call-with-muffled-conditions
-   thunk (append *uninteresting-compiler-conditions* *uninteresting-loader-conditions*)))
-(defmacro with-muffled-loader-conditions ((&optional) &body body)
-  "Run BODY where uninteresting compiler and additional loader conditions are muffled"
-  `(call-with-muffled-loader-conditions #'(lambda () , at body)))
+(with-upgradability ()
+  (defun call-with-muffled-compiler-conditions (thunk)
+    (call-with-muffled-conditions
+     thunk *uninteresting-compiler-conditions*))
+  (defmacro with-muffled-compiler-conditions ((&optional) &body body)
+    "Run BODY where uninteresting compiler conditions are muffled"
+    `(call-with-muffled-compiler-conditions #'(lambda () , at body)))
+  (defun call-with-muffled-loader-conditions (thunk)
+    (call-with-muffled-conditions
+     thunk (append *uninteresting-compiler-conditions* *uninteresting-loader-conditions*)))
+  (defmacro with-muffled-loader-conditions ((&optional) &body body)
+    "Run BODY where uninteresting compiler and additional loader conditions are muffled"
+    `(call-with-muffled-loader-conditions #'(lambda () , at body))))
 
 
 ;;;; Handle warnings and failures
-(define-condition compile-condition (condition)
-  ((context-format
-    :initform nil :reader compile-condition-context-format :initarg :context-format)
-   (context-arguments
-    :initform nil :reader compile-condition-context-arguments :initarg :context-arguments)
-   (description
-    :initform nil :reader compile-condition-description :initarg :description))
-  (:report (lambda (c s)
+(with-upgradability ()
+  (define-condition compile-condition (condition)
+    ((context-format
+      :initform nil :reader compile-condition-context-format :initarg :context-format)
+     (context-arguments
+      :initform nil :reader compile-condition-context-arguments :initarg :context-arguments)
+     (description
+      :initform nil :reader compile-condition-description :initarg :description))
+    (:report (lambda (c s)
                (format s (compatfmt "~@<~A~@[ while ~?~]~@:>")
                        (or (compile-condition-description c) (type-of c))
                        (compile-condition-context-format c)
                        (compile-condition-context-arguments c)))))
-(define-condition compile-file-error (compile-condition error) ())
-(define-condition compile-warned-warning (compile-condition warning) ())
-(define-condition compile-warned-error (compile-condition error) ())
-(define-condition compile-failed-warning (compile-condition warning) ())
-(define-condition compile-failed-error (compile-condition error) ())
-
-(defun* check-lisp-compile-warnings (warnings-p failure-p
-                                                &optional context-format context-arguments)
-  (when failure-p
-    (case *compile-file-failure-behaviour*
-      (:warn (warn 'compile-failed-warning
-                   :description "Lisp compilation failed"
-                   :context-format context-format
-                   :context-arguments context-arguments))
-      (:error (error 'compile-failed-error
-                   :description "Lisp compilation failed"
-                   :context-format context-format
-                   :context-arguments context-arguments))
-      (:ignore nil)))
-  (when warnings-p
-    (case *compile-file-warnings-behaviour*
-      (:warn (warn 'compile-warned-warning
-                   :description "Lisp compilation had style-warnings"
-                   :context-format context-format
-                   :context-arguments context-arguments))
-      (:error (error 'compile-warned-error
-                   :description "Lisp compilation had style-warnings"
-                   :context-format context-format
-                   :context-arguments context-arguments))
-      (:ignore nil))))
-
-(defun* check-lisp-compile-results (output warnings-p failure-p
-                                           &optional context-format context-arguments)
-  (unless output
-    (error 'compile-file-error :context-format context-format :context-arguments context-arguments))
-  (check-lisp-compile-warnings warnings-p failure-p context-format context-arguments))
+  (define-condition compile-file-error (compile-condition error) ())
+  (define-condition compile-warned-warning (compile-condition warning) ())
+  (define-condition compile-warned-error (compile-condition error) ())
+  (define-condition compile-failed-warning (compile-condition warning) ())
+  (define-condition compile-failed-error (compile-condition error) ())
+
+  (defun check-lisp-compile-warnings (warnings-p failure-p
+                                                  &optional context-format context-arguments)
+    (when failure-p
+      (case *compile-file-failure-behaviour*
+        (:warn (warn 'compile-failed-warning
+                     :description "Lisp compilation failed"
+                     :context-format context-format
+                     :context-arguments context-arguments))
+        (:error (error 'compile-failed-error
+                       :description "Lisp compilation failed"
+                       :context-format context-format
+                       :context-arguments context-arguments))
+        (:ignore nil)))
+    (when warnings-p
+      (case *compile-file-warnings-behaviour*
+        (:warn (warn 'compile-warned-warning
+                     :description "Lisp compilation had style-warnings"
+                     :context-format context-format
+                     :context-arguments context-arguments))
+        (:error (error 'compile-warned-error
+                       :description "Lisp compilation had style-warnings"
+                       :context-format context-format
+                       :context-arguments context-arguments))
+        (:ignore nil))))
+
+  (defun check-lisp-compile-results (output warnings-p failure-p
+                                             &optional context-format context-arguments)
+    (unless output
+      (error 'compile-file-error :context-format context-format :context-arguments context-arguments))
+    (check-lisp-compile-warnings warnings-p failure-p context-format context-arguments)))
 
 
 ;;;; Deferred-warnings treatment, originally implemented by Douglas Katzman.
-;;
-;; To support an implementation, three functions must be implemented:
-;; reify-deferred-warnings unreify-deferred-warnings reset-deferred-warnings
-;; See their respective docstrings.
-
-(defun reify-simple-sexp (sexp)
-  (etypecase sexp
-    (symbol (reify-symbol sexp))
-    ((or number character simple-string pathname) sexp)
-    (cons (cons (reify-simple-sexp (car sexp)) (reify-simple-sexp (cdr sexp))))))
-(defun unreify-simple-sexp (sexp)
-  (etypecase sexp
-    ((or symbol number character simple-string pathname) sexp)
-    (cons (cons (unreify-simple-sexp (car sexp)) (unreify-simple-sexp (cdr sexp))))
-    ((simple-vector 2) (unreify-symbol sexp))))
-
-#+clozure
-(progn
-  (defun reify-source-note (source-note)
-    (when source-note
-      (with-accessors ((source ccl::source-note-source) (filename ccl:source-note-filename)
-                       (start-pos ccl:source-note-start-pos) (end-pos ccl:source-note-end-pos)) source-note
+;;;
+;;; To support an implementation, three functions must be implemented:
+;;; reify-deferred-warnings unreify-deferred-warnings reset-deferred-warnings
+;;; See their respective docstrings.
+(with-upgradability ()
+  (defun reify-simple-sexp (sexp)
+    (etypecase sexp
+      (symbol (reify-symbol sexp))
+      ((or number character simple-string pathname) sexp)
+      (cons (cons (reify-simple-sexp (car sexp)) (reify-simple-sexp (cdr sexp))))))
+  (defun unreify-simple-sexp (sexp)
+    (etypecase sexp
+      ((or symbol number character simple-string pathname) sexp)
+      (cons (cons (unreify-simple-sexp (car sexp)) (unreify-simple-sexp (cdr sexp))))
+      ((simple-vector 2) (unreify-symbol sexp))))
+
+  #+clozure
+  (progn
+    (defun reify-source-note (source-note)
+      (when source-note
+        (with-accessors ((source ccl::source-note-source) (filename ccl:source-note-filename)
+                         (start-pos ccl:source-note-start-pos) (end-pos ccl:source-note-end-pos)) source-note
           (declare (ignorable source))
           (list :filename filename :start-pos start-pos :end-pos end-pos
                 #|:source (reify-source-note source)|#))))
-  (defun unreify-source-note (source-note)
-    (when source-note
-      (destructuring-bind (&key filename start-pos end-pos source) source-note
-        (ccl::make-source-note :filename filename :start-pos start-pos :end-pos end-pos
-                               :source (unreify-source-note source)))))
-  (defun reify-deferred-warning (deferred-warning)
-    (with-accessors ((warning-type ccl::compiler-warning-warning-type)
-                     (args ccl::compiler-warning-args)
-                     (source-note ccl:compiler-warning-source-note)
-                     (function-name ccl:compiler-warning-function-name)) deferred-warning
-      (list :warning-type warning-type :function-name (reify-simple-sexp function-name)
-            :source-note (reify-source-note source-note) :args (reify-simple-sexp args))))
-  (defun unreify-deferred-warning (reified-deferred-warning)
-    (destructuring-bind (&key warning-type function-name source-note args)
-        reified-deferred-warning
-      (make-condition (or (cdr (ccl::assq warning-type ccl::*compiler-whining-conditions*))
-                          'ccl::compiler-warning)
-                      :function-name (unreify-simple-sexp function-name)
-                      :source-note (unreify-source-note source-note)
-                      :warning-type warning-type
-                      :args (unreify-simple-sexp args)))))
-
-#+sbcl
-(defun reify-undefined-warning (warning)
-  ;; Extracting undefined-warnings from the compilation-unit
-  ;; To be passed through the above reify/unreify link, it must be a "simple-sexp"
-  (list*
-   (sb-c::undefined-warning-kind warning)
-   (sb-c::undefined-warning-name warning)
-   (sb-c::undefined-warning-count warning)
-   (mapcar
-    #'(lambda (frob)
-        ;; the lexenv slot can be ignored for reporting purposes
-        `(:enclosing-source ,(sb-c::compiler-error-context-enclosing-source frob)
-          :source ,(sb-c::compiler-error-context-source frob)
-          :original-source ,(sb-c::compiler-error-context-original-source frob)
-          :context ,(sb-c::compiler-error-context-context frob)
-          :file-name ,(sb-c::compiler-error-context-file-name frob) ; a pathname
-          :file-position ,(sb-c::compiler-error-context-file-position frob) ; an integer
-          :original-source-path ,(sb-c::compiler-error-context-original-source-path frob)))
-    (sb-c::undefined-warning-warnings warning))))
+    (defun unreify-source-note (source-note)
+      (when source-note
+        (destructuring-bind (&key filename start-pos end-pos source) source-note
+          (ccl::make-source-note :filename filename :start-pos start-pos :end-pos end-pos
+                                 :source (unreify-source-note source)))))
+    (defun reify-function-name (function-name)
+      (reify-simple-sexp
+       (if-let (setfed (gethash function-name ccl::%setf-function-name-inverses%))
+         `(setf ,setfed)
+         function-name)))
+    (defun unreify-function-name (function-name)
+      (let ((name (unreify-simple-sexp function-name)))
+        (if (and (consp name) (eq (first name) 'setf))
+            (let ((setfed (second name)))
+              (gethash setfed ccl::%setf-function-names%))
+            name)))
+    (defun reify-deferred-warning (deferred-warning)
+      (with-accessors ((warning-type ccl::compiler-warning-warning-type)
+                       (args ccl::compiler-warning-args)
+                       (source-note ccl:compiler-warning-source-note)
+                       (function-name ccl:compiler-warning-function-name)) deferred-warning
+        (list :warning-type warning-type :function-name (reify-function-name function-name)
+              :source-note (reify-source-note source-note)
+              :args (destructuring-bind (fun . formals) args
+                      (cons (reify-function-name fun) (reify-simple-sexp formals))))))
+    (defun unreify-deferred-warning (reified-deferred-warning)
+      (destructuring-bind (&key warning-type function-name source-note args)
+          reified-deferred-warning
+        (make-condition (or (cdr (ccl::assq warning-type ccl::*compiler-whining-conditions*))
+                            'ccl::compiler-warning)
+                        :function-name (unreify-function-name function-name)
+                        :source-note (unreify-source-note source-note)
+                        :warning-type warning-type
+                        :args (destructuring-bind (fun . formals) args
+                                (cons (unreify-function-name fun) (unreify-simple-sexp formals)))))))
+  #+(or cmu scl)
+  (defun reify-undefined-warning (warning)
+    ;; Extracting undefined-warnings from the compilation-unit
+    ;; To be passed through the above reify/unreify link, it must be a "simple-sexp"
+    (list*
+     (c::undefined-warning-kind warning)
+     (c::undefined-warning-name warning)
+     (c::undefined-warning-count warning)
+     (mapcar
+      #'(lambda (frob)
+          ;; the lexenv slot can be ignored for reporting purposes
+          `(:enclosing-source ,(c::compiler-error-context-enclosing-source frob)
+            :source ,(c::compiler-error-context-source frob)
+            :original-source ,(c::compiler-error-context-original-source frob)
+            :context ,(c::compiler-error-context-context frob)
+            :file-name ,(c::compiler-error-context-file-name frob) ; a pathname
+            :file-position ,(c::compiler-error-context-file-position frob) ; an integer
+            :original-source-path ,(c::compiler-error-context-original-source-path frob)))
+      (c::undefined-warning-warnings warning))))
+
+  #+sbcl
+  (defun reify-undefined-warning (warning)
+    ;; Extracting undefined-warnings from the compilation-unit
+    ;; To be passed through the above reify/unreify link, it must be a "simple-sexp"
+    (list*
+     (sb-c::undefined-warning-kind warning)
+     (sb-c::undefined-warning-name warning)
+     (sb-c::undefined-warning-count warning)
+     (mapcar
+      #'(lambda (frob)
+          ;; the lexenv slot can be ignored for reporting purposes
+          `(:enclosing-source ,(sb-c::compiler-error-context-enclosing-source frob)
+            :source ,(sb-c::compiler-error-context-source frob)
+            :original-source ,(sb-c::compiler-error-context-original-source frob)
+            :context ,(sb-c::compiler-error-context-context frob)
+            :file-name ,(sb-c::compiler-error-context-file-name frob) ; a pathname
+            :file-position ,(sb-c::compiler-error-context-file-position frob) ; an integer
+            :original-source-path ,(sb-c::compiler-error-context-original-source-path frob)))
+      (sb-c::undefined-warning-warnings warning))))
 
-(defun reify-deferred-warnings ()
-  "return a portable S-expression, portably readable and writeable in any Common Lisp implementation
+  (defun reify-deferred-warnings ()
+    "return a portable S-expression, portably readable and writeable in any Common Lisp implementation
 using READ within a WITH-SAFE-IO-SYNTAX, that represents the warnings currently deferred by
 WITH-COMPILATION-UNIT. One of three functions required for deferred-warnings support in ASDF."
-  #+clozure
-  (mapcar 'reify-deferred-warning
-          (if-let (dw ccl::*outstanding-deferred-warnings*)
-            (let ((mdw (ccl::ensure-merged-deferred-warnings dw)))
-              (ccl::deferred-warnings.warnings mdw))))
-  #+sbcl
-  (when sb-c::*in-compilation-unit*
-    ;; Try to send nothing through the pipe if nothing needs to be accumulated
-    `(,@(when sb-c::*undefined-warnings*
-          `((sb-c::*undefined-warnings*
-             ,@(mapcar #'reify-undefined-warning sb-c::*undefined-warnings*))))
-      ,@(loop :for what :in '(sb-c::*aborted-compilation-unit-count*
-                              sb-c::*compiler-error-count*
-                              sb-c::*compiler-warning-count*
-                              sb-c::*compiler-style-warning-count*
-                              sb-c::*compiler-note-count*)
-              :for value = (symbol-value what)
-              :when (plusp value)
-                :collect `(,what . ,value)))))
+    #+allegro
+    (reify-simple-sexp
+     (list :functions-defined excl::.functions-defined.
+           :functions-called excl::.functions-called.))
+    #+clozure
+    (mapcar 'reify-deferred-warning
+            (if-let (dw ccl::*outstanding-deferred-warnings*)
+              (let ((mdw (ccl::ensure-merged-deferred-warnings dw)))
+                (ccl::deferred-warnings.warnings mdw))))
+    #+(or cmu scl)
+    (when lisp::*in-compilation-unit*
+      ;; Try to send nothing through the pipe if nothing needs to be accumulated
+      `(,@(when c::*undefined-warnings*
+            `((c::*undefined-warnings*
+               ,@(mapcar #'reify-undefined-warning c::*undefined-warnings*))))
+        ,@(loop :for what :in '(c::*compiler-error-count*
+                                c::*compiler-warning-count*
+                                c::*compiler-note-count*)
+                :for value = (symbol-value what)
+                :when (plusp value)
+                  :collect `(,what . ,value))))
+    #+sbcl
+    (when sb-c::*in-compilation-unit*
+      ;; Try to send nothing through the pipe if nothing needs to be accumulated
+      `(,@(when sb-c::*undefined-warnings*
+            `((sb-c::*undefined-warnings*
+               ,@(mapcar #'reify-undefined-warning sb-c::*undefined-warnings*))))
+        ,@(loop :for what :in '(sb-c::*aborted-compilation-unit-count*
+                                sb-c::*compiler-error-count*
+                                sb-c::*compiler-warning-count*
+                                sb-c::*compiler-style-warning-count*
+                                sb-c::*compiler-note-count*)
+                :for value = (symbol-value what)
+                :when (plusp value)
+                  :collect `(,what . ,value)))))
 
-(defun unreify-deferred-warnings (reified-deferred-warnings)
-  "given a S-expression created by REIFY-DEFERRED-WARNINGS, reinstantiate the corresponding
+  (defun unreify-deferred-warnings (reified-deferred-warnings)
+    "given a S-expression created by REIFY-DEFERRED-WARNINGS, reinstantiate the corresponding
 deferred warnings as to be handled at the end of the current WITH-COMPILATION-UNIT.
 Handle any warning that has been resolved already,
 such as an undefined function that has been defined since.
 One of three functions required for deferred-warnings support in ASDF."
-  (declare (ignorable reified-deferred-warnings))
-  #+clozure
-  (let ((dw (or ccl::*outstanding-deferred-warnings*
-                (setf ccl::*outstanding-deferred-warnings* (ccl::%defer-warnings t)))))
-    (appendf (ccl::deferred-warnings.warnings dw)
-             (mapcar 'unreify-deferred-warning reified-deferred-warnings)))
-  #+sbcl
-  (dolist (item reified-deferred-warnings)
-    ;; Each item is (symbol . adjustment) where the adjustment depends on the symbol.
-    ;; For *undefined-warnings*, the adjustment is a list of initargs.
-    ;; For everything else, it's an integer.
-    (destructuring-bind (symbol . adjustment) item
-      (case symbol
-        ((sb-c::*undefined-warnings*)
-         (setf sb-c::*undefined-warnings*
-               (nconc (mapcan
-                       #'(lambda (stuff)
-                           (destructuring-bind (kind name count . rest) stuff
-                             (unless (case kind (:function (fboundp name)))
-                               (list
-                                (sb-c::make-undefined-warning
-                                 :name name
-                                 :kind kind
-                                 :count count
-                                 :warnings
-                                 (mapcar #'(lambda (x)
-                                             (apply #'sb-c::make-compiler-error-context x))
-                                         rest))))))
-                       adjustment)
-                      sb-c::*undefined-warnings*)))
-        (otherwise
-         (set symbol (+ (symbol-value symbol) adjustment)))))))
+    (declare (ignorable reified-deferred-warnings))
+    #+allegro
+    (destructuring-bind (&key functions-defined functions-called)
+        (unreify-simple-sexp reified-deferred-warnings)
+      (setf excl::.functions-defined.
+            (append functions-defined excl::.functions-defined.)
+            excl::.functions-called.
+            (append functions-called excl::.functions-called.)))
+    #+clozure
+    (let ((dw (or ccl::*outstanding-deferred-warnings*
+                  (setf ccl::*outstanding-deferred-warnings* (ccl::%defer-warnings t)))))
+      (appendf (ccl::deferred-warnings.warnings dw)
+               (mapcar 'unreify-deferred-warning reified-deferred-warnings)))
+    #+(or cmu scl)
+    (dolist (item reified-deferred-warnings)
+      ;; Each item is (symbol . adjustment) where the adjustment depends on the symbol.
+      ;; For *undefined-warnings*, the adjustment is a list of initargs.
+      ;; For everything else, it's an integer.
+      (destructuring-bind (symbol . adjustment) item
+        (case symbol
+          ((c::*undefined-warnings*)
+           (setf c::*undefined-warnings*
+                 (nconc (mapcan
+                         #'(lambda (stuff)
+                             (destructuring-bind (kind name count . rest) stuff
+                               (unless (case kind (:function (fboundp name)))
+                                 (list
+                                  (c::make-undefined-warning
+                                   :name name
+                                   :kind kind
+                                   :count count
+                                   :warnings
+                                   (mapcar #'(lambda (x)
+                                               (apply #'c::make-compiler-error-context x))
+                                           rest))))))
+                         adjustment)
+                        c::*undefined-warnings*)))
+          (otherwise
+           (set symbol (+ (symbol-value symbol) adjustment))))))
+    #+sbcl
+    (dolist (item reified-deferred-warnings)
+      ;; Each item is (symbol . adjustment) where the adjustment depends on the symbol.
+      ;; For *undefined-warnings*, the adjustment is a list of initargs.
+      ;; For everything else, it's an integer.
+      (destructuring-bind (symbol . adjustment) item
+        (case symbol
+          ((sb-c::*undefined-warnings*)
+           (setf sb-c::*undefined-warnings*
+                 (nconc (mapcan
+                         #'(lambda (stuff)
+                             (destructuring-bind (kind name count . rest) stuff
+                               (unless (case kind (:function (fboundp name)))
+                                 (list
+                                  (sb-c::make-undefined-warning
+                                   :name name
+                                   :kind kind
+                                   :count count
+                                   :warnings
+                                   (mapcar #'(lambda (x)
+                                               (apply #'sb-c::make-compiler-error-context x))
+                                           rest))))))
+                         adjustment)
+                        sb-c::*undefined-warnings*)))
+          (otherwise
+           (set symbol (+ (symbol-value symbol) adjustment)))))))
 
-(defun reset-deferred-warnings ()
-  "Reset the set of deferred warnings to be handled at the end of the current WITH-COMPILATION-UNIT.
+  (defun reset-deferred-warnings ()
+    "Reset the set of deferred warnings to be handled at the end of the current WITH-COMPILATION-UNIT.
 One of three functions required for deferred-warnings support in ASDF."
-  #+clozure
-  (if-let (dw ccl::*outstanding-deferred-warnings*)
-    (let ((mdw (ccl::ensure-merged-deferred-warnings dw)))
-      (setf (ccl::deferred-warnings.warnings mdw) nil)))
-  #+sbcl
-  (when sb-c::*in-compilation-unit*
-    (setf sb-c::*undefined-warnings* nil
-          sb-c::*aborted-compilation-unit-count* 0
-          sb-c::*compiler-error-count* 0
-          sb-c::*compiler-warning-count* 0
-          sb-c::*compiler-style-warning-count* 0
-          sb-c::*compiler-note-count* 0)))
+    #+allegro
+    (setf excl::.functions-defined. nil
+          excl::.functions-called. nil)
+    #+clozure
+    (if-let (dw ccl::*outstanding-deferred-warnings*)
+      (let ((mdw (ccl::ensure-merged-deferred-warnings dw)))
+        (setf (ccl::deferred-warnings.warnings mdw) nil)))
+    #+(or cmu scl)
+    (when lisp::*in-compilation-unit*
+      (setf c::*undefined-warnings* nil
+            c::*compiler-error-count* 0
+            c::*compiler-warning-count* 0
+            c::*compiler-note-count* 0))
+    #+sbcl
+    (when sb-c::*in-compilation-unit*
+      (setf sb-c::*undefined-warnings* nil
+            sb-c::*aborted-compilation-unit-count* 0
+            sb-c::*compiler-error-count* 0
+            sb-c::*compiler-warning-count* 0
+            sb-c::*compiler-style-warning-count* 0
+            sb-c::*compiler-note-count* 0)))
 
-(defun* save-deferred-warnings (warnings-file)
-  "Save forward reference conditions so they may be issued at a latter time,
+  (defun save-deferred-warnings (warnings-file)
+    "Save forward reference conditions so they may be issued at a latter time,
 possibly in a different process."
-  (with-open-file (s warnings-file :direction :output :if-exists :supersede)
-    (with-safe-io-syntax ()
-      (write (reify-deferred-warnings) :stream s :pretty t :readably t)
-      (terpri s)))
-  (reset-deferred-warnings))
-
-(defun* warnings-file-type (&optional implementation-type)
-  (case (or implementation-type *implementation-type*)
-    (:sbcl "sbcl-warnings")
-    ((:clozure :ccl) "ccl-warnings")))
-
-(defvar *warnings-file-type* (warnings-file-type)
-  "Type for warnings files")
-
-(defun* warnings-file-p (file &optional implementation-type)
-  (if-let (type (if implementation-type
-                    (warnings-file-type implementation-type)
-                    *warnings-file-type*))
-    (equal (pathname-type file) type)))
-
-(defun* check-deferred-warnings (files &optional context-format context-arguments)
-  (let ((file-errors nil)
-        (failure-p nil)
-        (warnings-p nil))
-    (handler-bind
-        ((warning #'(lambda (c)
-                      (setf warnings-p t)
-                      (unless (typep c 'style-warning)
-                        (setf failure-p t)))))
-      (with-compilation-unit (:override t)
-        (reset-deferred-warnings)
-        (dolist (file files)
-          (unreify-deferred-warnings
-           (handler-case (safe-read-file-form file)
-             (error (c)
-               (delete-file-if-exists file)
-               (push c file-errors)
-               nil))))))
-    (dolist (error file-errors) (error error))
-    (check-lisp-compile-warnings
-     (or failure-p warnings-p) failure-p context-format context-arguments)))
-
-
-;;;; Deferred warnings
-#|
-Mini-guide to adding support for deferred warnings on an implementation.
-
-First, look at what such a warning looks like:
-
-(describe
- (handler-case
-     (and (eval '(lambda () (some-undefined-function))) nil)
-   (t (c) c)))
-
-Then you can grep for the condition type in your compiler sources
-and see how to catch those that have been deferred,
-and/or read, clear and restore the deferred list.
-
-ccl::
-undefined-function-reference
-verify-deferred-warning
-report-deferred-warnings
-
-|#
-
-(defun* call-with-saved-deferred-warnings (thunk warnings-file)
-  (if warnings-file
-      (with-compilation-unit (:override t)
-        (let (#+sbcl (sb-c::*undefined-warnings* nil))
-          (multiple-value-prog1
-              (with-muffled-compiler-conditions ()
-                (funcall thunk))
-            (save-deferred-warnings warnings-file)
-            (reset-deferred-warnings))))
-      (funcall thunk)))
+    (with-open-file (s warnings-file :direction :output :if-exists :supersede
+                       :element-type *default-stream-element-type*
+                       :external-format *utf-8-external-format*)
+      (with-safe-io-syntax ()
+        (write (reify-deferred-warnings) :stream s :pretty t :readably t)
+        (terpri s))))
+
+  (defun warnings-file-type (&optional implementation-type)
+    (case (or implementation-type *implementation-type*)
+      ((:acl :allegro) "allegro-warnings")
+      ;;((:clisp) "clisp-warnings")
+      ((:cmu :cmucl) "cmucl-warnings")
+      ((:sbcl) "sbcl-warnings")
+      ((:clozure :ccl) "ccl-warnings")
+      ((:scl) "scl-warnings")))
+
+  (defvar *warnings-file-type* (warnings-file-type)
+    "Type for warnings files")
+
+  (defun warnings-file-p (file &optional implementation-type)
+    (if-let (type (if implementation-type
+                      (warnings-file-type implementation-type)
+                      *warnings-file-type*))
+      (equal (pathname-type file) type)))
+
+  (defun check-deferred-warnings (files &optional context-format context-arguments)
+    (let ((file-errors nil)
+          (failure-p nil)
+          (warnings-p nil))
+      (handler-bind
+          ((warning #'(lambda (c)
+                        (setf warnings-p t)
+                        (unless (typep c 'style-warning)
+                          (setf failure-p t)))))
+        (with-compilation-unit (:override t)
+          (reset-deferred-warnings)
+          (dolist (file files)
+            (unreify-deferred-warnings
+             (handler-case (safe-read-file-form file)
+               (error (c)
+                 (delete-file-if-exists file)
+                 (push c file-errors)
+                 nil))))))
+      (dolist (error file-errors) (error error))
+      (check-lisp-compile-warnings
+       (or failure-p warnings-p) failure-p context-format context-arguments)))
+
+  #|
+  Mini-guide to adding support for deferred warnings on an implementation.
+
+  First, look at what such a warning looks like:
+
+  (describe
+  (handler-case
+  (and (eval '(lambda () (some-undefined-function))) nil)
+  (t (c) c)))
+
+  Then you can grep for the condition type in your compiler sources
+  and see how to catch those that have been deferred,
+  and/or read, clear and restore the deferred list.
+
+  Also look at
+  (macroexpand-1 '(with-compilation-unit () foo))
+  |#
+
+  (defun call-with-saved-deferred-warnings (thunk warnings-file)
+    (if warnings-file
+        (with-compilation-unit (:override t)
+          (unwind-protect
+               (let (#+sbcl (sb-c::*undefined-warnings* nil))
+                 (multiple-value-prog1
+                     (funcall thunk)
+                   (save-deferred-warnings warnings-file)))
+            (reset-deferred-warnings)))
+        (funcall thunk)))
 
-(defmacro with-saved-deferred-warnings ((warnings-file) &body body)
-  "If WARNINGS-FILE is not nil, records the deferred-warnings around the BODY
+  (defmacro with-saved-deferred-warnings ((warnings-file) &body body)
+    "If WARNINGS-FILE is not nil, records the deferred-warnings around the BODY
 and saves those warnings to the given file for latter use,
 possibly in a different process. Otherwise just run the BODY."
-  `(call-with-saved-deferred-warnings #'(lambda () , at body) ,warnings-file))
+    `(call-with-saved-deferred-warnings #'(lambda () , at body) ,warnings-file)))
 
 
 ;;; from ASDF
-
-(defun* current-lisp-file-pathname ()
-  (or *compile-file-pathname* *load-pathname*))
-
-(defun* load-pathname ()
-  *load-pathname*)
-
-(defun* lispize-pathname (input-file)
-  (make-pathname :type "lisp" :defaults input-file))
-
-(defun* compile-file-type (&rest keys)
-  "pathname TYPE for lisp FASt Loading files"
-  (declare (ignorable keys))
-  #-(or ecl mkcl) (load-time-value (pathname-type (compile-file-pathname "foo.lisp")))
-  #+(or ecl mkcl) (pathname-type (apply 'compile-file-pathname "foo" keys)))
-
-(defun* call-around-hook (hook function)
-  (call-function (or hook 'funcall) function))
-
-(defun* compile-file-pathname* (input-file &rest keys &key output-file &allow-other-keys)
-  (let* ((keys
-           (remove-plist-keys `(#+(and allegro (not (version>= 8 2))) :external-format
-                            ,@(unless output-file '(:output-file))) keys)))
-    (if (absolute-pathname-p output-file)
-        ;; what cfp should be doing, w/ mp* instead of mp
-        (let* ((type (pathname-type (apply 'compile-file-type keys)))
-               (defaults (make-pathname
-                          :type type :defaults (merge-pathnames* input-file))))
-          (merge-pathnames* output-file defaults))
-        (funcall *output-translation-function*
-                 (apply 'compile-file-pathname input-file keys)))))
-
-(defun* (compile-file*) (input-file &rest keys
-                                    &key compile-check output-file warnings-file
-                                    #+clisp lib-file #+(or ecl mkcl) object-file
-                                    &allow-other-keys)
-  "This function provides a portable wrapper around COMPILE-FILE.
+(with-upgradability ()
+  (defun current-lisp-file-pathname ()
+    (or *compile-file-pathname* *load-pathname*))
+
+  (defun load-pathname ()
+    *load-pathname*)
+
+  (defun lispize-pathname (input-file)
+    (make-pathname :type "lisp" :defaults input-file))
+
+  (defun compile-file-type (&rest keys)
+    "pathname TYPE for lisp FASt Loading files"
+    (declare (ignorable keys))
+    #-(or ecl mkcl) (load-time-value (pathname-type (compile-file-pathname "foo.lisp")))
+    #+(or ecl mkcl) (pathname-type (apply 'compile-file-pathname "foo" keys)))
+
+  (defun call-around-hook (hook function)
+    (call-function (or hook 'funcall) function))
+
+  (defun compile-file-pathname* (input-file &rest keys &key output-file &allow-other-keys)
+    (let* ((keys
+             (remove-plist-keys `(#+(and allegro (not (version>= 8 2))) :external-format
+                                    ,@(unless output-file '(:output-file))) keys)))
+      (if (absolute-pathname-p output-file)
+          ;; what cfp should be doing, w/ mp* instead of mp
+          (let* ((type (pathname-type (apply 'compile-file-type keys)))
+                 (defaults (make-pathname
+                            :type type :defaults (merge-pathnames* input-file))))
+            (merge-pathnames* output-file defaults))
+          (funcall *output-translation-function*
+                   (apply 'compile-file-pathname input-file keys)))))
+
+  (defun* (compile-file*) (input-file &rest keys
+                                      &key compile-check output-file warnings-file
+                                      #+clisp lib-file #+(or ecl mkcl) object-file
+                                      &allow-other-keys)
+    "This function provides a portable wrapper around COMPILE-FILE.
 It ensures that the OUTPUT-FILE value is only returned and
 the file only actually created if the compilation was successful,
 even though your implementation may not do that, and including
@@ -4367,111 +4603,113 @@
 On ECL or MKCL, it creates both the linkable object and loadable fasl files.
 On implementations that erroneously do not recognize standard keyword arguments,
 it will filter them appropriately."
-  #+ecl (when (and object-file (equal (compile-file-type) (pathname object-file)))
-          (format t "Whoa, some funky ASDF upgrade switched ~S calling convention for ~S and ~S~%"
-                  'compile-file* output-file object-file)
-          (rotatef output-file object-file))
-  (let* ((keywords (remove-plist-keys
-                    `(:output-file :compile-check :warnings-file
-                      #+clisp :lib-file #+(or ecl mkcl) :object-file
-                      #+gcl2.6 ,@'(:external-format :print :verbose)) keys))
-         (output-file
-           (or output-file
-               (apply 'compile-file-pathname* input-file :output-file output-file keywords)))
-         #+ecl
-         (object-file
-           (unless (use-ecl-byte-compiler-p)
+    #+ecl (when (and object-file (equal (compile-file-type) (pathname object-file)))
+            (format t "Whoa, some funky ASDF upgrade switched ~S calling convention for ~S and ~S~%"
+                    'compile-file* output-file object-file)
+            (rotatef output-file object-file))
+    (let* ((keywords (remove-plist-keys
+                      `(:output-file :compile-check :warnings-file
+                                     #+clisp :lib-file #+(or ecl mkcl) :object-file
+                                     #+gcl2.6 ,@'(:external-format :print :verbose)) keys))
+           (output-file
+             (or output-file
+                 (apply 'compile-file-pathname* input-file :output-file output-file keywords)))
+           #+ecl
+           (object-file
+             (unless (use-ecl-byte-compiler-p)
+               (or object-file
+                   (compile-file-pathname output-file :type :object))))
+           #+mkcl
+           (object-file
              (or object-file
-                 (compile-file-pathname output-file :type :object))))
-         #+mkcl
-         (object-file
-           (or object-file
-               (compile-file-pathname output-file :fasl-p nil)))
-         (tmp-file (tmpize-pathname output-file))
-         #+clisp
-         (tmp-lib (make-pathname :type "lib" :defaults tmp-file)))
-    (multiple-value-bind (output-truename warnings-p failure-p)
-        (with-saved-deferred-warnings (warnings-file)
-          (or #-(or ecl mkcl) (apply 'compile-file input-file :output-file tmp-file keywords)
-              #+ecl (apply 'compile-file input-file :output-file
-                           (if object-file
-                               (list* object-file :system-p t keywords)
-                               (list* tmp-file keywords)))
-              #+mkcl (apply 'compile-file input-file
-                            :output-file object-file :fasl-p nil keywords)))
-      (cond
-        ((and output-truename
-              (flet ((check-flag (flag behaviour)
-                       (or (not flag) (member behaviour '(:success :warn :ignore)))))
-                (and (check-flag failure-p *compile-file-failure-behaviour*)
-                     (check-flag warnings-p *compile-file-warnings-behaviour*)))
-              (progn
-                #+(or ecl mkcl)
-                (when (and #+ecl object-file)
-                  (setf output-truename
-                        (compiler::build-fasl
-                         tmp-file #+ecl :lisp-files #+mkcl :lisp-object-files
-                                  (list object-file))))
-                (or (not compile-check)
-                    (apply compile-check input-file :output-file tmp-file keywords))))
-         (delete-file-if-exists output-file)
-         (when output-truename
-           #+clisp (when lib-file (rename-file-overwriting-target tmp-lib lib-file))
-           (rename-file-overwriting-target output-truename output-file)
-           (setf output-truename (truename output-file)))
-         #+clisp (delete-file-if-exists tmp-lib))
-        (t ;; error or failed check
-         (delete-file-if-exists output-truename)
-         (setf output-truename nil)))
-      (values output-truename warnings-p failure-p))))
-
-(defun* load* (x &rest keys &key &allow-other-keys)
-  (etypecase x
-    ((or pathname string #-(or allegro clozure gcl2.6 genera) stream)
-     (apply 'load x
-            #-gcl2.6 keys #+gcl2.6 (remove-plist-key :external-format keys)))
-    ;; GCL 2.6, Genera can't load from a string-input-stream
-    ;; ClozureCL 1.6 can only load from file input stream
-    ;; Allegro 5, I don't remember but it must have been broken when I tested.
-    #+(or allegro clozure gcl2.6 genera)
-    (stream ;; make do this way
-     (let ((*package* *package*)
-           (*readtable* *readtable*)
-           (*load-pathname* nil)
-           (*load-truename* nil))
-       (eval-input x)))))
-
-(defun* load-from-string (string)
-  "Portably read and evaluate forms from a STRING."
-  (with-input-from-string (s string) (load* s)))
+                 (compile-file-pathname output-file :fasl-p nil)))
+           (tmp-file (tmpize-pathname output-file))
+           #+clisp
+           (tmp-lib (make-pathname :type "lib" :defaults tmp-file)))
+      (multiple-value-bind (output-truename warnings-p failure-p)
+          (with-saved-deferred-warnings (warnings-file)
+            (with-muffled-compiler-conditions ()
+              (or #-(or ecl mkcl) (apply 'compile-file input-file :output-file tmp-file keywords)
+                  #+ecl (apply 'compile-file input-file :output-file
+                               (if object-file
+                                   (list* object-file :system-p t keywords)
+                                   (list* tmp-file keywords)))
+                  #+mkcl (apply 'compile-file input-file
+                                :output-file object-file :fasl-p nil keywords))))
+        (cond
+          ((and output-truename
+                (flet ((check-flag (flag behaviour)
+                         (or (not flag) (member behaviour '(:success :warn :ignore)))))
+                  (and (check-flag failure-p *compile-file-failure-behaviour*)
+                       (check-flag warnings-p *compile-file-warnings-behaviour*)))
+                (progn
+                  #+(or ecl mkcl)
+                  (when (and #+ecl object-file)
+                    (setf output-truename
+                          (compiler::build-fasl
+                           tmp-file #+ecl :lisp-files #+mkcl :lisp-object-files
+                                    (list object-file))))
+                  (or (not compile-check)
+                      (apply compile-check input-file :output-file tmp-file keywords))))
+           (delete-file-if-exists output-file)
+           (when output-truename
+             #+clisp (when lib-file (rename-file-overwriting-target tmp-lib lib-file))
+             (rename-file-overwriting-target output-truename output-file)
+             (setf output-truename (truename output-file)))
+           #+clisp (delete-file-if-exists tmp-lib))
+          (t ;; error or failed check
+           (delete-file-if-exists output-truename)
+           (setf output-truename nil)))
+        (values output-truename warnings-p failure-p))))
+
+  (defun load* (x &rest keys &key &allow-other-keys)
+    (etypecase x
+      ((or pathname string #-(or allegro clozure gcl2.6 genera) stream)
+       (apply 'load x
+              #-gcl2.6 keys #+gcl2.6 (remove-plist-key :external-format keys)))
+      ;; GCL 2.6, Genera can't load from a string-input-stream
+      ;; ClozureCL 1.6 can only load from file input stream
+      ;; Allegro 5, I don't remember but it must have been broken when I tested.
+      #+(or allegro clozure gcl2.6 genera)
+      (stream ;; make do this way
+       (let ((*package* *package*)
+             (*readtable* *readtable*)
+             (*load-pathname* nil)
+             (*load-truename* nil))
+         (eval-input x)))))
+
+  (defun load-from-string (string)
+    "Portably read and evaluate forms from a STRING."
+    (with-input-from-string (s string) (load* s))))
 
 ;;; Links FASLs together
-(defun* combine-fasls (inputs output)
-  #-(or allegro clisp clozure cmu lispworks sbcl scl xcl)
-  (error "~A does not support ~S~%inputs ~S~%output  ~S"
-         (implementation-type) 'combine-fasls inputs output)
-  #+clozure (ccl:fasl-concatenate output inputs :if-exists :supersede)
-  #+(or allegro clisp cmu sbcl scl xcl) (concatenate-files inputs output)
-  #+lispworks
-  (let (fasls)
-    (unwind-protect
-         (progn
-           (loop :for i :in inputs
-                 :for n :from 1
-                 :for f = (add-pathname-suffix
-                           output (format nil "-FASL~D" n))
-                 :do #-lispworks-personal-edition (lispworks:copy-file i f)
-                     #+lispworks-personal-edition (concatenate-files (list i) f)
-                     (push f fasls))
-           (ignore-errors (lispworks:delete-system :fasls-to-concatenate))
-           (eval `(scm:defsystem :fasls-to-concatenate
-                    (:default-pathname ,(pathname-directory-pathname output))
-                    :members
-                    ,(loop :for f :in (reverse fasls)
-                           :collect `(,(namestring f) :load-only t))))
-           (scm:concatenate-system output :fasls-to-concatenate))
-      (loop :for f :in fasls :do (ignore-errors (delete-file f)))
-      (ignore-errors (lispworks:delete-system :fasls-to-concatenate)))))
+(with-upgradability ()
+  (defun combine-fasls (inputs output)
+    #-(or allegro clisp clozure cmu lispworks sbcl scl xcl)
+    (error "~A does not support ~S~%inputs ~S~%output  ~S"
+           (implementation-type) 'combine-fasls inputs output)
+    #+clozure (ccl:fasl-concatenate output inputs :if-exists :supersede)
+    #+(or allegro clisp cmu sbcl scl xcl) (concatenate-files inputs output)
+    #+lispworks
+    (let (fasls)
+      (unwind-protect
+           (progn
+             (loop :for i :in inputs
+                   :for n :from 1
+                   :for f = (add-pathname-suffix
+                             output (format nil "-FASL~D" n))
+                   :do #-lispworks-personal-edition (lispworks:copy-file i f)
+                   #+lispworks-personal-edition (concatenate-files (list i) f)
+                                                (push f fasls))
+             (ignore-errors (lispworks:delete-system :fasls-to-concatenate))
+             (eval `(scm:defsystem :fasls-to-concatenate
+                      (:default-pathname ,(pathname-directory-pathname output))
+                      :members
+                      ,(loop :for f :in (reverse fasls)
+                             :collect `(,(namestring f) :load-only t))))
+             (scm:concatenate-system output :fasls-to-concatenate))
+        (loop :for f :in fasls :do (ignore-errors (delete-file f)))
+        (ignore-errors (lispworks:delete-system :fasls-to-concatenate))))))
 
 ;;;; ---------------------------------------------------------------------------
 ;;;; Generic support for configuration files
@@ -4479,7 +4717,7 @@
 (asdf/package:define-package :asdf/configuration
   (:recycle :asdf/configuration :asdf)
   (:use :asdf/common-lisp :asdf/utility
-   :asdf/pathname :asdf/stream :asdf/os :asdf/image)
+   :asdf/os :asdf/pathname :asdf/filesystem :asdf/stream :asdf/image)
   (:export
    #:get-folder-path
    #:user-configuration-directories #:system-configuration-directories
@@ -4490,277 +4728,286 @@
    #:report-invalid-form #:invalid-configuration #:*ignored-configuration-form*
    #:*clear-configuration-hook* #:clear-configuration #:register-clear-configuration-hook
    #:resolve-location #:location-designator-p #:location-function-p #:*here-directory*
-   #:resolve-relative-location #:resolve-absolute-location))
+   #:resolve-relative-location #:resolve-absolute-location #:upgrade-configuration))
 (in-package :asdf/configuration)
 
-(define-condition invalid-configuration ()
-  ((form :reader condition-form :initarg :form)
-   (location :reader condition-location :initarg :location)
-   (format :reader condition-format :initarg :format)
-   (arguments :reader condition-arguments :initarg :arguments :initform nil))
-  (:report (lambda (c s)
+(with-upgradability ()
+  (define-condition invalid-configuration ()
+    ((form :reader condition-form :initarg :form)
+     (location :reader condition-location :initarg :location)
+     (format :reader condition-format :initarg :format)
+     (arguments :reader condition-arguments :initarg :arguments :initform nil))
+    (:report (lambda (c s)
                (format s (compatfmt "~@<~? (will be skipped)~@:>")
                        (condition-format c)
                        (list* (condition-form c) (condition-location c)
                               (condition-arguments c))))))
 
-(defun* get-folder-path (folder)
-  (or ;; this semi-portably implements a subset of the functionality of lispworks' sys:get-folder-path
-   #+(and lispworks mswindows) (sys:get-folder-path folder)
-   ;; read-windows-registry HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders\AppData
-   (ecase folder
-    (:local-appdata (getenv-absolute-directory "LOCALAPPDATA"))
-    (:appdata (getenv-absolute-directory "APPDATA"))
-    (:common-appdata (or (getenv-absolute-directory "ALLUSERSAPPDATA")
-                         (subpathname* (getenv-absolute-directory "ALLUSERSPROFILE") "Application Data/"))))))
-
-(defun* user-configuration-directories ()
-  (let ((dirs
-         `(,@(when (os-unix-p)
-               (cons
-                (subpathname* (getenv-absolute-directory "XDG_CONFIG_HOME") "common-lisp/")
-                (loop :for dir :in (getenv-absolute-directories "XDG_CONFIG_DIRS")
-                  :collect (subpathname* dir "common-lisp/"))))
-           ,@(when (os-windows-p)
-               `(,(subpathname* (get-folder-path :local-appdata) "common-lisp/config/")
-                 ,(subpathname* (get-folder-path :appdata) "common-lisp/config/")))
-           ,(subpathname (user-homedir-pathname) ".config/common-lisp/"))))
-    (remove-duplicates (remove-if-not #'absolute-pathname-p dirs)
-                       :from-end t :test 'equal)))
+  (defun get-folder-path (folder)
+    (or ;; this semi-portably implements a subset of the functionality of lispworks' sys:get-folder-path
+        #+(and lispworks mswindows) (sys:get-folder-path folder)
+        ;; read-windows-registry HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders\AppData
+        (ecase folder
+          (:local-appdata (getenv-absolute-directory "LOCALAPPDATA"))
+          (:appdata (getenv-absolute-directory "APPDATA"))
+          (:common-appdata (or (getenv-absolute-directory "ALLUSERSAPPDATA")
+                               (subpathname* (getenv-absolute-directory "ALLUSERSPROFILE") "Application Data/"))))))
+
+  (defun user-configuration-directories ()
+    (let ((dirs
+            `(,@(when (os-unix-p)
+                  (cons
+                   (subpathname* (getenv-absolute-directory "XDG_CONFIG_HOME") "common-lisp/")
+                   (loop :for dir :in (getenv-absolute-directories "XDG_CONFIG_DIRS")
+                         :collect (subpathname* dir "common-lisp/"))))
+              ,@(when (os-windows-p)
+                  `(,(subpathname* (get-folder-path :local-appdata) "common-lisp/config/")
+                    ,(subpathname* (get-folder-path :appdata) "common-lisp/config/")))
+              ,(subpathname (user-homedir-pathname) ".config/common-lisp/"))))
+      (remove-duplicates (remove-if-not #'absolute-pathname-p dirs)
+                         :from-end t :test 'equal)))
 
-(defun* system-configuration-directories ()
-  (cond
-    ((os-unix-p) '(#p"/etc/common-lisp/"))
-    ((os-windows-p)
-     (if-let (it (subpathname* (get-folder-path :common-appdata) "common-lisp/config/"))
-       (list it)))))
-
-(defun* in-first-directory (dirs x &key (direction :input))
-  (loop :with fun = (ecase direction
-                      ((nil :input :probe) 'probe-file*)
-                      ((:output :io) 'identity))
-    :for dir :in dirs
-    :thereis (and dir (funcall fun (merge-pathnames* x (ensure-directory-pathname dir))))))
-
-(defun* in-user-configuration-directory (x &key (direction :input))
-  (in-first-directory (user-configuration-directories) x :direction direction))
-(defun* in-system-configuration-directory (x &key (direction :input))
-  (in-first-directory (system-configuration-directories) x :direction direction))
-
-(defun* configuration-inheritance-directive-p (x)
-  (let ((kw '(:inherit-configuration :ignore-inherited-configuration)))
-    (or (member x kw)
-        (and (length=n-p x 1) (member (car x) kw)))))
-
-(defun* report-invalid-form (reporter &rest args)
-  (etypecase reporter
-    (null
-     (apply 'error 'invalid-configuration args))
-    (function
-     (apply reporter args))
-    ((or symbol string)
-     (apply 'error reporter args))
-    (cons
-     (apply 'apply (append reporter args)))))
-
-(defvar *ignored-configuration-form* nil)
-
-(defun* validate-configuration-form (form tag directive-validator
-                                    &key location invalid-form-reporter)
-  (unless (and (consp form) (eq (car form) tag))
-    (setf *ignored-configuration-form* t)
-    (report-invalid-form invalid-form-reporter :form form :location location)
-    (return-from validate-configuration-form nil))
-  (loop :with inherit = 0 :with ignore-invalid-p = nil :with x = (list tag)
-    :for directive :in (cdr form)
-    :when (cond
-            ((configuration-inheritance-directive-p directive)
-             (incf inherit) t)
-            ((eq directive :ignore-invalid-entries)
-             (setf ignore-invalid-p t) t)
-            ((funcall directive-validator directive)
-             t)
-            (ignore-invalid-p
-             nil)
-            (t
-             (setf *ignored-configuration-form* t)
-             (report-invalid-form invalid-form-reporter :form directive :location location)
-             nil))
-    :do (push directive x)
-    :finally
-    (unless (= inherit 1)
-      (report-invalid-form invalid-form-reporter
-             :arguments (list (compatfmt "~@<One and only one of ~S or ~S is required.~@:>")
-                              :inherit-configuration :ignore-inherited-configuration)))
-    (return (nreverse x))))
-
-(defun* validate-configuration-file (file validator &key description)
-  (let ((forms (read-file-forms file)))
-    (unless (length=n-p forms 1)
-      (error (compatfmt "~@<One and only one form allowed for ~A. Got: ~3i~_~S~@:>~%")
-             description forms))
-    (funcall validator (car forms) :location file)))
+  (defun system-configuration-directories ()
+    (cond
+      ((os-unix-p) '(#p"/etc/common-lisp/"))
+      ((os-windows-p)
+       (if-let (it (subpathname* (get-folder-path :common-appdata) "common-lisp/config/"))
+         (list it)))))
+
+  (defun in-first-directory (dirs x &key (direction :input))
+    (loop :with fun = (ecase direction
+                        ((nil :input :probe) 'probe-file*)
+                        ((:output :io) 'identity))
+          :for dir :in dirs
+          :thereis (and dir (funcall fun (merge-pathnames* x (ensure-directory-pathname dir))))))
+
+  (defun in-user-configuration-directory (x &key (direction :input))
+    (in-first-directory (user-configuration-directories) x :direction direction))
+  (defun in-system-configuration-directory (x &key (direction :input))
+    (in-first-directory (system-configuration-directories) x :direction direction))
+
+  (defun configuration-inheritance-directive-p (x)
+    (let ((kw '(:inherit-configuration :ignore-inherited-configuration)))
+      (or (member x kw)
+          (and (length=n-p x 1) (member (car x) kw)))))
+
+  (defun report-invalid-form (reporter &rest args)
+    (etypecase reporter
+      (null
+       (apply 'error 'invalid-configuration args))
+      (function
+       (apply reporter args))
+      ((or symbol string)
+       (apply 'error reporter args))
+      (cons
+       (apply 'apply (append reporter args)))))
+
+  (defvar *ignored-configuration-form* nil)
+
+  (defun validate-configuration-form (form tag directive-validator
+                                            &key location invalid-form-reporter)
+    (unless (and (consp form) (eq (car form) tag))
+      (setf *ignored-configuration-form* t)
+      (report-invalid-form invalid-form-reporter :form form :location location)
+      (return-from validate-configuration-form nil))
+    (loop :with inherit = 0 :with ignore-invalid-p = nil :with x = (list tag)
+          :for directive :in (cdr form)
+          :when (cond
+                  ((configuration-inheritance-directive-p directive)
+                   (incf inherit) t)
+                  ((eq directive :ignore-invalid-entries)
+                   (setf ignore-invalid-p t) t)
+                  ((funcall directive-validator directive)
+                   t)
+                  (ignore-invalid-p
+                   nil)
+                  (t
+                   (setf *ignored-configuration-form* t)
+                   (report-invalid-form invalid-form-reporter :form directive :location location)
+                   nil))
+            :do (push directive x)
+          :finally
+             (unless (= inherit 1)
+               (report-invalid-form invalid-form-reporter
+                                    :arguments (list (compatfmt "~@<One and only one of ~S or ~S is required.~@:>")
+                                                     :inherit-configuration :ignore-inherited-configuration)))
+             (return (nreverse x))))
+
+  (defun validate-configuration-file (file validator &key description)
+    (let ((forms (read-file-forms file)))
+      (unless (length=n-p forms 1)
+        (error (compatfmt "~@<One and only one form allowed for ~A. Got: ~3i~_~S~@:>~%")
+               description forms))
+      (funcall validator (car forms) :location file)))
 
-(defun* validate-configuration-directory (directory tag validator &key invalid-form-reporter)
-  "Map the VALIDATOR across the .conf files in DIRECTORY, the TAG will
+  (defun validate-configuration-directory (directory tag validator &key invalid-form-reporter)
+    "Map the VALIDATOR across the .conf files in DIRECTORY, the TAG will
 be applied to the results to yield a configuration form.  Current
 values of TAG include :source-registry and :output-translations."
-  (let ((files (sort (ignore-errors
-                       (remove-if
-                        'hidden-pathname-p
-                        (directory* (make-pathname :name *wild* :type "conf" :defaults directory))))
-                     #'string< :key #'namestring)))
-    `(,tag
-      ,@(loop :for file :in files :append
-          (loop :with ignore-invalid-p = nil
-            :for form :in (read-file-forms file)
-            :when (eq form :ignore-invalid-entries)
-              :do (setf ignore-invalid-p t)
-            :else
-              :when (funcall validator form)
-                :collect form
-              :else
-                :when ignore-invalid-p
-                  :do (setf *ignored-configuration-form* t)
-                :else
-                  :do (report-invalid-form invalid-form-reporter :form form :location file)))
-      :inherit-configuration)))
-
-(defun* resolve-relative-location (x &key ensure-directory wilden)
-  (ensure-pathname
-   (etypecase x
-     (pathname x)
-     (string (parse-unix-namestring
-              x :ensure-directory ensure-directory))
-     (cons
-      (if (null (cdr x))
-          (resolve-relative-location
-           (car x) :ensure-directory ensure-directory :wilden wilden)
-          (let* ((car (resolve-relative-location
-                       (car x) :ensure-directory t :wilden nil)))
-            (merge-pathnames*
-             (resolve-relative-location
-              (cdr x) :ensure-directory ensure-directory :wilden wilden)
-             car))))
-     ((eql :*/) *wild-directory*)
-     ((eql :**/) *wild-inferiors*)
-     ((eql :*.*.*) *wild-file*)
-     ((eql :implementation)
-      (parse-unix-namestring
-       (implementation-identifier) :ensure-directory t))
-     ((eql :implementation-type)
-      (parse-unix-namestring
-       (string-downcase (implementation-type)) :ensure-directory t))
-     ((eql :hostname)
-      (parse-unix-namestring (hostname) :ensure-directory t)))
-  :wilden (and wilden (not (pathnamep x)) (not (member x '(:*/ :**/ :*.*.*))))
-  :want-relative t))
+    (let ((files (sort (ignore-errors
+                        (remove-if
+                         'hidden-pathname-p
+                         (directory* (make-pathname :name *wild* :type "conf" :defaults directory))))
+                       #'string< :key #'namestring)))
+      `(,tag
+        ,@(loop :for file :in files :append
+                                    (loop :with ignore-invalid-p = nil
+                                          :for form :in (read-file-forms file)
+                                          :when (eq form :ignore-invalid-entries)
+                                            :do (setf ignore-invalid-p t)
+                                          :else
+                                            :when (funcall validator form)
+                                              :collect form
+                                          :else
+                                            :when ignore-invalid-p
+                                              :do (setf *ignored-configuration-form* t)
+                                          :else
+                                            :do (report-invalid-form invalid-form-reporter :form form :location file)))
+        :inherit-configuration)))
+
+  (defun resolve-relative-location (x &key ensure-directory wilden)
+    (ensure-pathname
+     (etypecase x
+       (pathname x)
+       (string (parse-unix-namestring
+                x :ensure-directory ensure-directory))
+       (cons
+        (if (null (cdr x))
+            (resolve-relative-location
+             (car x) :ensure-directory ensure-directory :wilden wilden)
+            (let* ((car (resolve-relative-location
+                         (car x) :ensure-directory t :wilden nil)))
+              (merge-pathnames*
+               (resolve-relative-location
+                (cdr x) :ensure-directory ensure-directory :wilden wilden)
+               car))))
+       ((eql :*/) *wild-directory*)
+       ((eql :**/) *wild-inferiors*)
+       ((eql :*.*.*) *wild-file*)
+       ((eql :implementation)
+        (parse-unix-namestring
+         (implementation-identifier) :ensure-directory t))
+       ((eql :implementation-type)
+        (parse-unix-namestring
+         (string-downcase (implementation-type)) :ensure-directory t))
+       ((eql :hostname)
+        (parse-unix-namestring (hostname) :ensure-directory t)))
+     :wilden (and wilden (not (pathnamep x)) (not (member x '(:*/ :**/ :*.*.*))))
+     :want-relative t))
 
-(defvar *here-directory* nil
-  "This special variable is bound to the currect directory during calls to
+  (defvar *here-directory* nil
+    "This special variable is bound to the currect directory during calls to
 PROCESS-SOURCE-REGISTRY in order that we be able to interpret the :here
 directive.")
 
-(defvar *user-cache* nil
-  "A specification as per RESOLVE-LOCATION of where the user keeps his FASL cache")
+  (defvar *user-cache* nil
+    "A specification as per RESOLVE-LOCATION of where the user keeps his FASL cache")
 
-(defun compute-user-cache ()
-  (setf *user-cache*
-        (flet ((try (x &rest sub) (and x `(,x , at sub))))
-          (or
-           (try (getenv-absolute-directory "XDG_CACHE_HOME") "common-lisp" :implementation)
-           (when (os-windows-p)
-             (try (or (get-folder-path :local-appdata)
-                      (get-folder-path :appdata))
-                  "common-lisp" "cache" :implementation))
-           '(:home ".cache" "common-lisp" :implementation)))))
-(register-image-restore-hook 'compute-user-cache)
-
-(defun* resolve-absolute-location (x &key ensure-directory wilden)
-  (ensure-pathname
-   (etypecase x
-     (pathname x)
-     (string
-      (let ((p #-mcl (parse-namestring x)
-               #+mcl (probe-posix x)))
-        #+mcl (unless p (error "POSIX pathname ~S does not exist" x))
-        (if ensure-directory (ensure-directory-pathname p) p)))
-     (cons
-      (return-from resolve-absolute-location
-        (if (null (cdr x))
-            (resolve-absolute-location
-             (car x) :ensure-directory ensure-directory :wilden wilden)
-            (merge-pathnames*
-             (resolve-relative-location
-              (cdr x) :ensure-directory ensure-directory :wilden wilden)
-             (resolve-absolute-location
-              (car x) :ensure-directory t :wilden nil)))))
-     ((eql :root)
-      ;; special magic! we return a relative pathname,
-      ;; but what it means to the output-translations is
-      ;; "relative to the root of the source pathname's host and device".
-      (return-from resolve-absolute-location
-        (let ((p (make-pathname* :directory '(:relative))))
-          (if wilden (wilden p) p))))
-     ((eql :home) (user-homedir-pathname))
-     ((eql :here) (resolve-absolute-location
-                   *here-directory* :ensure-directory t :wilden nil))
-     ((eql :user-cache) (resolve-absolute-location
-                         *user-cache* :ensure-directory t :wilden nil)))
-   :wilden (and wilden (not (pathnamep x)))
-   :resolve-symlinks *resolve-symlinks*
-   :want-absolute t))
-
-;; Try to override declaration in previous versions of ASDF.
-(declaim (ftype (function (t &key (:directory boolean) (:wilden boolean)
-                             (:ensure-directory boolean)) t) resolve-location))
-
-(defun* (resolve-location) (x &key ensure-directory wilden directory)
-  ;; :directory backward compatibility, until 2014-01-16: accept directory as well as ensure-directory
-  (loop* :with dirp = (or directory ensure-directory)
-         :with (first . rest) = (if (atom x) (list x) x)
-         :with path = (resolve-absolute-location
-                       first :ensure-directory (and (or dirp rest) t)
-                             :wilden (and wilden (null rest)))
-         :for (element . morep) :on rest
-         :for dir = (and (or morep dirp) t)
-         :for wild = (and wilden (not morep))
-         :for sub = (merge-pathnames*
-                     (resolve-relative-location
-                      element :ensure-directory dir :wilden wild)
-                     path)
-         :do (setf path (if (absolute-pathname-p sub) (resolve-symlinks* sub) sub))
-         :finally (return path)))
-
-(defun* location-designator-p (x)
-  (flet ((absolute-component-p (c)
-           (typep c '(or string pathname
-                      (member :root :home :here :user-cache))))
-         (relative-component-p (c)
-           (typep c '(or string pathname
-                      (member :*/ :**/ :*.*.* :implementation :implementation-type)))))
-    (or (typep x 'boolean)
-        (absolute-component-p x)
-        (and (consp x) (absolute-component-p (first x)) (every #'relative-component-p (rest x))))))
-
-(defun* location-function-p (x)
-  (and
-   (length=n-p x 2)
-   (eq (car x) :function)
-   (or (symbolp (cadr x))
-       (and (consp (cadr x))
-            (eq (caadr x) 'lambda)
-            (length=n-p (cadadr x) 2)))))
-
-(defvar *clear-configuration-hook* '())
+  (defun compute-user-cache ()
+    (setf *user-cache*
+          (flet ((try (x &rest sub) (and x `(,x , at sub))))
+            (or
+             (try (getenv-absolute-directory "XDG_CACHE_HOME") "common-lisp" :implementation)
+             (when (os-windows-p)
+               (try (or (get-folder-path :local-appdata)
+                        (get-folder-path :appdata))
+                    "common-lisp" "cache" :implementation))
+             '(:home ".cache" "common-lisp" :implementation)))))
+  (register-image-restore-hook 'compute-user-cache)
+
+  (defun resolve-absolute-location (x &key ensure-directory wilden)
+    (ensure-pathname
+     (etypecase x
+       (pathname x)
+       (string
+        (let ((p #-mcl (parse-namestring x)
+                 #+mcl (probe-posix x)))
+          #+mcl (unless p (error "POSIX pathname ~S does not exist" x))
+          (if ensure-directory (ensure-directory-pathname p) p)))
+       (cons
+        (return-from resolve-absolute-location
+          (if (null (cdr x))
+              (resolve-absolute-location
+               (car x) :ensure-directory ensure-directory :wilden wilden)
+              (merge-pathnames*
+               (resolve-relative-location
+                (cdr x) :ensure-directory ensure-directory :wilden wilden)
+               (resolve-absolute-location
+                (car x) :ensure-directory t :wilden nil)))))
+       ((eql :root)
+        ;; special magic! we return a relative pathname,
+        ;; but what it means to the output-translations is
+        ;; "relative to the root of the source pathname's host and device".
+        (return-from resolve-absolute-location
+          (let ((p (make-pathname* :directory '(:relative))))
+            (if wilden (wilden p) p))))
+       ((eql :home) (user-homedir-pathname))
+       ((eql :here) (resolve-absolute-location
+                     *here-directory* :ensure-directory t :wilden nil))
+       ((eql :user-cache) (resolve-absolute-location
+                           *user-cache* :ensure-directory t :wilden nil)))
+     :wilden (and wilden (not (pathnamep x)))
+     :resolve-symlinks *resolve-symlinks*
+     :want-absolute t))
+
+  ;; Try to override declaration in previous versions of ASDF.
+  (declaim (ftype (function (t &key (:directory boolean) (:wilden boolean)
+                               (:ensure-directory boolean)) t) resolve-location))
+
+  (defun* (resolve-location) (x &key ensure-directory wilden directory)
+    ;; :directory backward compatibility, until 2014-01-16: accept directory as well as ensure-directory
+    (loop* :with dirp = (or directory ensure-directory)
+           :with (first . rest) = (if (atom x) (list x) x)
+           :with path = (resolve-absolute-location
+                         first :ensure-directory (and (or dirp rest) t)
+                               :wilden (and wilden (null rest)))
+           :for (element . morep) :on rest
+           :for dir = (and (or morep dirp) t)
+           :for wild = (and wilden (not morep))
+           :for sub = (merge-pathnames*
+                       (resolve-relative-location
+                        element :ensure-directory dir :wilden wild)
+                       path)
+           :do (setf path (if (absolute-pathname-p sub) (resolve-symlinks* sub) sub))
+           :finally (return path)))
+
+  (defun location-designator-p (x)
+    (flet ((absolute-component-p (c)
+             (typep c '(or string pathname
+                        (member :root :home :here :user-cache))))
+           (relative-component-p (c)
+             (typep c '(or string pathname
+                        (member :*/ :**/ :*.*.* :implementation :implementation-type)))))
+      (or (typep x 'boolean)
+          (absolute-component-p x)
+          (and (consp x) (absolute-component-p (first x)) (every #'relative-component-p (rest x))))))
+
+  (defun location-function-p (x)
+    (and
+     (length=n-p x 2)
+     (eq (car x) :function)
+     (or (symbolp (cadr x))
+         (and (consp (cadr x))
+              (eq (caadr x) 'lambda)
+              (length=n-p (cadadr x) 2)))))
+
+  (defvar *clear-configuration-hook* '())
+
+  (defun register-clear-configuration-hook (hook-function &optional call-now-p)
+    (register-hook-function '*clear-configuration-hook* hook-function call-now-p))
+
+  (defun clear-configuration ()
+    (call-functions *clear-configuration-hook*))
+
+  (register-image-dump-hook 'clear-configuration)
+
+  ;; If a previous version of ASDF failed to read some configuration, try again.
+  (defun upgrade-configuration ()
+    (when *ignored-configuration-form*
+      (clear-configuration)
+      (setf *ignored-configuration-form* nil))))
 
-(defun* register-clear-configuration-hook (hook-function &optional call-now-p)
-  (register-hook-function '*clear-configuration-hook* hook-function call-now-p))
 
-(defun* clear-configuration ()
-  (call-functions *clear-configuration-hook*))
-
-(register-image-dump-hook 'clear-configuration)
 ;;;; -------------------------------------------------------------------------
 ;;; Hacks for backward-compatibility of the driver
 
@@ -4778,42 +5025,43 @@
 
 ;;;; Backward compatibility with various pathname functions.
 
-(defun* coerce-pathname (name &key type defaults)
-  ;; For backward-compatibility only, for people using internals
-  ;; Reported users in quicklisp: hu.dwim.asdf, asdf-utils, xcvb
-  ;; Will be removed after 2014-01-16.
-  ;;(warn "Please don't use ASDF::COERCE-PATHNAME. Use ASDF/PATHNAME:PARSE-UNIX-NAMESTRING.")
-  (parse-unix-namestring name :type type :defaults defaults))
-
-(defun* component-name-to-pathname-components (unix-style-namestring
-                                               &key force-directory force-relative)
-  ;; Will be removed after 2014-01-16.
-  ;; (warn "Please don't use ASDF::COMPONENT-NAME-TO-PATHNAME-COMPONENTS, use SPLIT-UNIX-NAMESTRING-DIRECTORY-COMPONENTS")
-  (multiple-value-bind (relabs path filename file-only)
-      (split-unix-namestring-directory-components
-       unix-style-namestring :ensure-directory force-directory)
-    (declare (ignore file-only))
-    (when (and force-relative (not (eq relabs :relative)))
-      (error (compatfmt "~@<Absolute pathname designator not allowed: ~3i~_~S~@:>")
-             unix-style-namestring))
-    (values relabs path filename)))
+(with-upgradability ()
+  (defun coerce-pathname (name &key type defaults)
+    ;; For backward-compatibility only, for people using internals
+    ;; Reported users in quicklisp: hu.dwim.asdf, asdf-utils, xcvb
+    ;; Will be removed after 2014-01-16.
+    ;;(warn "Please don't use ASDF::COERCE-PATHNAME. Use ASDF/PATHNAME:PARSE-UNIX-NAMESTRING.")
+    (parse-unix-namestring name :type type :defaults defaults))
+
+  (defun component-name-to-pathname-components (unix-style-namestring
+                                                 &key force-directory force-relative)
+    ;; Will be removed after 2014-01-16.
+    ;; (warn "Please don't use ASDF::COMPONENT-NAME-TO-PATHNAME-COMPONENTS, use SPLIT-UNIX-NAMESTRING-DIRECTORY-COMPONENTS")
+    (multiple-value-bind (relabs path filename file-only)
+        (split-unix-namestring-directory-components
+         unix-style-namestring :ensure-directory force-directory)
+      (declare (ignore file-only))
+      (when (and force-relative (not (eq relabs :relative)))
+        (error (compatfmt "~@<Absolute pathname designator not allowed: ~3i~_~S~@:>")
+               unix-style-namestring))
+      (values relabs path filename)))
 
-#+(or ecl mkcl)
-(defun* compile-file-keeping-object (&rest args) (apply #'compile-file* args))
+  #+(or ecl mkcl)
+  (defun compile-file-keeping-object (&rest args) (apply #'compile-file* args)))
 ;;;; ---------------------------------------------------------------------------
 ;;;; Re-export all the functionality in asdf/driver
 
 (asdf/package:define-package :asdf/driver
-  (:nicknames :d :asdf-driver :asdf-utils)
+  (:nicknames :asdf-driver :asdf-utils)
   (:use :asdf/common-lisp :asdf/package :asdf/utility
-   :asdf/pathname :asdf/stream :asdf/os :asdf/image
+    :asdf/os :asdf/pathname :asdf/stream :asdf/filesystem :asdf/image
    :asdf/run-program :asdf/lisp-build
    :asdf/configuration :asdf/backward-driver)
   (:reexport
    ;; NB: excluding asdf/common-lisp
    ;; which include all of CL with compatibility modifications on select platforms.
    :asdf/package :asdf/utility
-   :asdf/pathname :asdf/stream :asdf/os :asdf/image
+    :asdf/os :asdf/pathname :asdf/stream :asdf/filesystem :asdf/image
    :asdf/run-program :asdf/lisp-build
    :asdf/configuration :asdf/backward-driver))
 ;;;; -------------------------------------------------------------------------
@@ -4822,13 +5070,12 @@
 
 (asdf/package:define-package :asdf/upgrade
   (:recycle :asdf/upgrade :asdf)
-  (:use :asdf/common-lisp :asdf/package :asdf/utility)
+  (:use :asdf/common-lisp :asdf/driver)
   (:export
-   #:upgrade-asdf #:asdf-upgrade-error #:when-upgrade
-   #:*asdf-upgrade-already-attempted*
+   #:asdf-version #:*previous-asdf-versions* #:*asdf-version*
+   #:asdf-message #:*verbose-out*
+   #:upgrading-p #:when-upgrading #:upgrade-asdf #:asdf-upgrade-error
    #:*post-upgrade-cleanup-hook* #:*post-upgrade-restart-hook* #:cleanup-upgraded-asdf
-   #:asdf-version #:*upgraded-p* #:*asdf-version*
-   #:asdf-message #:*asdf-verbose* #:*verbose-out*
    ;; There will be no symbol left behind!
    #:intern*)
   (:import-from :asdf/package #:intern* #:find-symbol*))
@@ -4836,40 +5083,66 @@
 
 ;;; Special magic to detect if this is an upgrade
 
-(eval-when (:load-toplevel :compile-toplevel :execute)
+(with-upgradability ()
+  (defun asdf-version ()
+    "Exported interface to the version of ASDF currently installed. A string.
+You can compare this string with e.g.: (ASDF:VERSION-SATISFIES (ASDF:ASDF-VERSION) \"3.4.5.67\")."
+    (when (find-package :asdf)
+      (or (symbol-value (find-symbol (string :*asdf-version*) :asdf))
+          (let* ((revsym (find-symbol (string :*asdf-revision*) :asdf))
+                 (rev (and revsym (boundp revsym) (symbol-value revsym))))
+            (etypecase rev
+              (string rev)
+              (cons (format nil "~{~D~^.~}" rev))
+              (null "1.0"))))))
   (defvar *asdf-version* nil)
-  (defvar *upgraded-p* nil)
-  (defvar *asdf-verbose* nil) ; was t from 2.000 to 2.014.12.
+  (defvar *previous-asdf-versions* nil)
   (defvar *verbose-out* nil)
-  (defun* asdf-message (format-string &rest format-args)
-    (apply 'format *verbose-out* format-string format-args)))
-
-(eval-when (:load-toplevel :compile-toplevel :execute)
+  (defun asdf-message (format-string &rest format-args)
+    (when *verbose-out* (apply 'format *verbose-out* format-string format-args)))
+  (defvar *post-upgrade-cleanup-hook* ())
+  (defvar *post-upgrade-restart-hook* ())
+  (defun upgrading-p ()
+    (and *previous-asdf-versions* (not (equal *asdf-version* (first *previous-asdf-versions*)))))
+  (defmacro when-upgrading ((&key (upgrading-p '(upgrading-p)) when) &body body)
+    `(with-upgradability ()
+       (when (and ,upgrading-p ,@(when when `(,when)))
+         (handler-bind ((style-warning #'muffle-warning))
+           (eval '(progn , at body))))))
   (let* (;; For bug reporting sanity, please always bump this version when you modify this file.
-         ;; Please also modify asdf.asd to reflect this change. make bump-version
+         ;; Please also modify asdf.asd to reflect this change. make bump-version v=3.4.5.67.8
          ;; can help you do these changes in synch (look at the source for documentation).
          ;; Relying on its automation, the version is now redundantly present on top of this file.
-         ;; "2.345" would be an official release
-         ;; "2.345.6" would be a development version in the official upstream
-         ;; "2.345.0.7" would be your seventh local modification of official release 2.345
-         ;; "2.345.6.7" would be your seventh local modification of development version 2.345.6
-         (asdf-version "2.26.158.1")
-         (existing-asdf (find-class (find-symbol* :component :asdf nil) nil))
-         (existing-version *asdf-version*)
-         (already-there (equal asdf-version existing-version))
-         (redefined-functions ;; gf signature and/or semantics changed incompatibly. Oops.
-           '(#:component-relative-pathname #:component-parent-pathname ;; component
-             #:source-file-type
-             #:find-system #:system-source-file #:system-relative-pathname ;; system
+         ;; "3.4" would be the general branch for major version 3, minor version 4.
+         ;; "3.4.5" would be an official release in the 3.4 branch.
+         ;; "3.4.5.67" would be a development version in the official upstream of 3.4.5.
+         ;; "3.4.5.0.8" would be your eighth local modification of official release 3.4.5
+         ;; "3.4.5.67.8" would be your eighth local modification of development version 3.4.5.67
+         (asdf-version "2.29")
+         (existing-version (asdf-version)))
+    (setf *asdf-version* asdf-version)
+    (when (and existing-version (not (equal asdf-version existing-version)))
+      (push existing-version *previous-asdf-versions*)
+      (when (or *load-verbose* *verbose-out*)
+        (format *trace-output*
+                (compatfmt "~&~@<; ~@;Upgrading ASDF ~@[from version ~A ~]to version ~A~@:>~%")
+                existing-version asdf-version)))))
+
+(when-upgrading ()
+  (let ((redefined-functions ;; gf signature and/or semantics changed incompatibly. Oops.
+          '(#:component-relative-pathname #:component-parent-pathname ;; component
+            #:source-file-type
+            #:find-system #:system-source-file #:system-relative-pathname ;; system
              #:find-component ;; find-component
              #:explain #:perform #:perform-with-restarts #:input-files #:output-files ;; action
              #:component-depends-on #:component-self-dependencies #:operation-done-p
              #:traverse ;; plan
              #:operate  ;; operate
+             #:parse-component-form ;; defsystem
              #:apply-output-translations ;; output-translations
              #:process-output-translations-directive
              #:inherit-source-registry #:process-source-registry ;; source-registry
-             #:process-source-registry-directive 
+             #:process-source-registry-directive
              #:trivial-system-p ;; bundle
              ;; NB: it's too late to do anything about asdf-driver functions!
              ))
@@ -4879,96 +5152,62 @@
              #:resolve-relative-location-component #:resolve-absolute-location-component
              #:output-files-for-system-and-operation))) ; obsolete ASDF-BINARY-LOCATION function
     (declare (ignorable redefined-functions uninterned-symbols))
-    (setf *asdf-version* asdf-version)
-    (when (and existing-asdf (not already-there))
-      (push existing-version *upgraded-p*)
-      (when *asdf-verbose*
-        (format *trace-output*
-                (compatfmt "~&~@<; ~@;Upgrading ASDF ~@[from version ~A ~]to version ~A~@:>~%")
-                existing-version asdf-version))
-      (loop :for name :in (append #-(or clisp ecl) redefined-functions)
-              :for sym = (find-symbol* name :asdf nil) :do
-                (when sym
-                  ;;(format t "Undefining ~S~%" sym);XXX
-                  (fmakunbound sym)))
-        (loop :with asdf = (find-package :asdf)
-              :for name :in (append #+(or clisp ecl) redefined-functions uninterned-symbols) ;XXX
-              :for sym = (find-symbol* name :asdf nil)
-              :for base-pkg = (and sym (symbol-package sym)) :do
-                (when sym
-                  ;;(format t "frobbing symbol ~S~%" sym);XXX
-                  (cond
-                    ((or (eq base-pkg asdf) (not base-pkg))
-                     (unintern* sym asdf)
-                     (intern* sym asdf))
-                    (t
-                     (unintern* sym base-pkg)
-                     (let ((new (intern* sym base-pkg)))
-                       (shadowing-import new asdf))))))
-        ;; Note that this massive package destruction makes it impossible
-        ;; to use asdf/driver on top of an old ASDF on these implementations
-        #+(or xcl)
-        (let ((p (find-package :asdf)))
-          (when p
-            (do-symbols (s p) (when (home-package-p s p) (nuke-symbol s)))
-            (rename-package-away p :prefix (format nil "~A-~A" :asdf (or existing-version :1.x))
-                         :index 0 :separator "-"))))))
-
-
-;;; Upgrade interface
-
-(defun* asdf-upgrade-error ()
-  ;; Important notice for whom it concerns. The crux of the matter is that
-  ;; TRAVERSE can be completely refactored, and so after the find-system returns, it's too late.
-  (error "When a system transitively depends on ASDF, it must :defsystem-depends-on (:asdf)~%~
-          Otherwise, when you upgrade ASDF, you must do it before you operate on any system.~%"))
-
-(defmacro when-upgrade ((&key (upgraded-p '*upgraded-p*) when) &body body)
-  `(eval-when (:compile-toplevel :load-toplevel :execute)
-     (when (and ,upgraded-p ,@(when when `(,when)))
-       (handler-bind ((style-warning #'muffle-warning))
-         (eval '(progn , at body))))))
-
-(defun* asdf-version ()
-  "Exported interface to the version of ASDF currently installed. A string.
-You can compare this string with e.g.:
-(ASDF:VERSION-SATISFIES (ASDF:ASDF-VERSION) \"2.345.67\")."
-  *asdf-version*)
+    (loop :for name :in (append #-(or ecl) redefined-functions)
+          :for sym = (find-symbol* name :asdf nil) :do
+            (when sym
+              (fmakunbound sym)))
+    (loop :with asdf = (find-package :asdf)
+          :for name :in (append #+(or ecl) redefined-functions uninterned-symbols) ;XXX
+          :for sym = (find-symbol* name :asdf nil)
+          :for base-pkg = (and sym (symbol-package sym)) :do
+            (when sym
+              (cond
+                ((or (eq base-pkg asdf) (not base-pkg))
+                 (unintern* sym asdf)
+                 (intern* sym asdf))
+                (t
+                 (unintern* sym base-pkg)
+                 (let ((new (intern* sym base-pkg)))
+                   (shadowing-import new asdf))))))))
 
 
 ;;; Self-upgrade functions
 
-(defvar *post-upgrade-cleanup-hook* ())
-(defvar *post-upgrade-restart-hook* ())
-
-(defun* cleanup-upgraded-asdf (old-version)
-  (let ((new-version (asdf-version)))
-    (unless (equal old-version new-version)
-      (cond
-        ((version-compatible-p new-version old-version)
-         (asdf-message (compatfmt "~&~@<; ~@;Upgraded ASDF from version ~A to version ~A~@:>~%")
-                       old-version new-version))
-        ((version-compatible-p old-version new-version)
-         (warn (compatfmt "~&~@<; ~@;Downgraded ASDF from version ~A to version ~A~@:>~%")
-               old-version new-version))
-        (t
-         (asdf-message (compatfmt "~&~@<; ~@;Changed ASDF from version ~A to incompatible version ~A~@:>~%")
-                       old-version new-version)))
-      (dolist (h (reverse *post-upgrade-cleanup-hook*))
-        (funcall (ensure-function h)))
-      (dolist (h *post-upgrade-restart-hook*)
-        (funcall (ensure-function h)))
-      t)))
+(with-upgradability ()
+  (defun asdf-upgrade-error ()
+    ;; Important notice for whom it concerns. The crux of the matter is that
+    ;; TRAVERSE can be completely refactored, and so after the find-system returns, it's too late.
+    (error "When a system transitively depends on ASDF, it must :defsystem-depends-on (:asdf)~%~
+          Otherwise, when you upgrade from ASDF 2, you must do it before you operate on any system.~%"))
+
+  (defun cleanup-upgraded-asdf (&optional (old-version (first *previous-asdf-versions*)))
+    (let ((new-version (asdf-version)))
+      (unless (equal old-version new-version)
+        (push new-version *previous-asdf-versions*)
+        (when old-version
+          (cond
+            ((version-compatible-p new-version old-version)
+             (asdf-message (compatfmt "~&~@<; ~@;Upgraded ASDF from version ~A to version ~A~@:>~%")
+                           old-version new-version))
+            ((version-compatible-p old-version new-version)
+             (warn (compatfmt "~&~@<; ~@;Downgraded ASDF from version ~A to version ~A~@:>~%")
+                   old-version new-version))
+            (t
+             (asdf-message (compatfmt "~&~@<; ~@;Changed ASDF from version ~A to incompatible version ~A~@:>~%")
+                           old-version new-version)))
+          (call-functions (reverse *post-upgrade-cleanup-hook*))
+          t))))
 
-(defun* upgrade-asdf ()
-  "Try to upgrade of ASDF. If a different version was used, return T.
+  (defun upgrade-asdf ()
+    "Try to upgrade of ASDF. If a different version was used, return T.
    We need do that before we operate on anything that may possibly depend on ASDF."
-  (let ((version (asdf-version))
-        (*load-print* nil)
-        (*compile-print* nil))
-    (handler-bind (((or style-warning warning) #'muffle-warning))
-      (symbol-call :asdf :load-system :asdf :verbose nil))
-    (cleanup-upgraded-asdf version)))
+    (let ((*load-print* nil)
+          (*compile-print* nil))
+      (handler-bind (((or style-warning warning) #'muffle-warning))
+        (symbol-call :asdf :load-system :asdf :verbose nil))))
+
+  (register-hook-function '*post-upgrade-cleanup-hook* 'upgrade-configuration))
+
 ;;;; -------------------------------------------------------------------------
 ;;;; Components
 
@@ -5005,130 +5244,142 @@
    #:author #:maintainer #:licence #:source-file #:defsystem-depends-on
    #:sibling-dependencies #:if-feature #:in-order-to #:inline-methods
    #:relative-pathname #:absolute-pathname #:operation-times #:around-compile
-   #:%encoding #:properties #:parent))
+   #:%encoding #:properties #:component-properties #:parent))
 (in-package :asdf/component)
 
-(defgeneric* component-name (component)
-  (:documentation "Name of the COMPONENT, unique relative to its parent"))
-(defgeneric* component-system (component)
-  (:documentation "Find the top-level system containing COMPONENT"))
-(defgeneric* component-pathname (component)
-  (:documentation "Extracts the pathname applicable for a particular component."))
-(defgeneric* (component-relative-pathname) (component)
-  (:documentation "Returns a pathname for the component argument intended to be
+(with-upgradability ()
+  (defgeneric component-name (component)
+    (:documentation "Name of the COMPONENT, unique relative to its parent"))
+  (defgeneric component-system (component)
+    (:documentation "Find the top-level system containing COMPONENT"))
+  (defgeneric component-pathname (component)
+    (:documentation "Extracts the pathname applicable for a particular component."))
+  (defgeneric (component-relative-pathname) (component)
+    (:documentation "Returns a pathname for the component argument intended to be
 interpreted relative to the pathname of that component's parent.
 Despite the function's name, the return value may be an absolute
 pathname, because an absolute pathname may be interpreted relative to
 another pathname in a degenerate way."))
-(defgeneric* component-external-format (component))
-(defgeneric* component-encoding (component))
-(defgeneric* version-satisfies (component version))
-
-;;; Backward compatible way of computing the FILE-TYPE of a component.
-;;; TODO: find users, have them stop using that.
-(defgeneric* (source-file-type) (component system))
+  (defgeneric component-external-format (component))
+  (defgeneric component-encoding (component))
+  (defgeneric version-satisfies (component version))
+  (defgeneric component-version (component))
+  (defgeneric (setf component-version) (new-version component))
+  (defgeneric component-parent (component))
+  (defmethod component-parent ((component null)) (declare (ignorable component)) nil)
+
+  ;; Backward compatible way of computing the FILE-TYPE of a component.
+  ;; TODO: find users, have them stop using that, remove it for ASDF4.
+  (defgeneric (source-file-type) (component system)))
 
-(when-upgrade (:when (find-class 'component nil))
+(when-upgrading (:when (find-class 'component nil))
   (defmethod reinitialize-instance :after ((c component) &rest initargs &key)
     (declare (ignorable c initargs)) (values)))
 
-(defclass component ()
-  ((name :accessor component-name :initarg :name :type string :documentation
-         "Component name: designator for a string composed of portable pathname characters")
-   ;; We might want to constrain version with
-   ;; :type (and string (satisfies parse-version))
-   ;; but we cannot until we fix all systems that don't use it correctly!
-   (version :accessor component-version :initarg :version)
-   (description :accessor component-description :initarg :description)
-   (long-description :accessor component-long-description :initarg :long-description)
-   (sibling-dependencies :accessor component-sibling-dependencies :initform nil)
-   (if-feature :accessor component-if-feature :initform nil :initarg :if-feature)
-   ;; In the ASDF object model, dependencies exist between *actions*
-   ;; (an action is a pair of operation and component).
-   ;; Dependencies are represented as alists of operations
-   ;; to dependencies (other actions) in each component.
-   ;; Up until ASDF 2.26.9, there used to be two kinds of dependencies:
-   ;; in-order-to and do-first, each stored in its own slot. Now there is only in-order-to.
-   ;; in-order-to used to represent things that modify the filesystem (such as compiling a fasl)
-   ;; and do-first things that modify the current image (such as loading a fasl).
-   ;; These are now unified because we now correctly propagate timestamps between dependencies.
-   ;; Happily, no one seems to have used do-first too much, but the name in-order-to remains.
-   ;; The names are bad, but they have been the official API since Dan Barlow's ASDF 1.52!
-   ;; LispWorks's defsystem has caused-by and requires for in-order-to and do-first respectively.
-   ;; Maybe rename the slots in ASDF? But that's not very backward-compatible.
-   ;; See our ASDF 2 paper for more complete explanations.
-   (in-order-to :initform nil :initarg :in-order-to
-                :accessor component-in-order-to)
-   ;; methods defined using the "inline" style inside a defsystem form:
-   ;; need to store them somewhere so we can delete them when the system
-   ;; is re-evaluated
-   (inline-methods :accessor component-inline-methods :initform nil) ;; OBSOLETE! DELETE THIS IF NO ONE USES.
-   ;; no direct accessor for pathname, we do this as a method to allow
-   ;; it to default in funky ways if not supplied
-   (relative-pathname :initarg :pathname)
-   ;; the absolute-pathname is computed based on relative-pathname...
-   (absolute-pathname)
-   (operation-times :initform (make-hash-table)
-                    :accessor component-operation-times)
-   (around-compile :initarg :around-compile)
-   (properties) ;; Only for backward-compatibility during upgrades from ASDF2. DO NOT USE.
-   (%encoding :accessor %component-encoding :initform nil :initarg :encoding)
-   ;; For backward-compatibility, this slot is part of component rather than child-component. ASDF4: don't.
-   (parent :initarg :parent :initform nil :reader component-parent)
-   (build-operation
-    :initarg :build-operation :initform nil :reader component-build-operation)))
-
-(defun* component-find-path (component)
-  (check-type component (or null component))
-  (reverse
-   (loop :for c = component :then (component-parent c)
-         :while c :collect (component-name c))))
-
-(defmethod print-object ((c component) stream)
-  (print-unreadable-object (c stream :type t :identity nil)
-    (format stream "~{~S~^ ~}" (component-find-path c))))
-
-(defmethod component-system ((component component))
-  (if-let (system (component-parent component))
-    (component-system system)
-    component))
+(with-upgradability ()
+  (defclass component ()
+    ((name :accessor component-name :initarg :name :type string :documentation
+           "Component name: designator for a string composed of portable pathname characters")
+     ;; We might want to constrain version with
+     ;; :type (and string (satisfies parse-version))
+     ;; but we cannot until we fix all systems that don't use it correctly!
+     (version :accessor component-version :initarg :version :initform nil)
+     (description :accessor component-description :initarg :description :initform nil)
+     (long-description :accessor component-long-description :initarg :long-description :initform nil)
+     (sibling-dependencies :accessor component-sibling-dependencies :initform nil)
+     (if-feature :accessor component-if-feature :initform nil :initarg :if-feature)
+     ;; In the ASDF object model, dependencies exist between *actions*,
+     ;; where an action is a pair of an operation and a component.
+     ;; Dependencies are represented as alists of operations
+     ;; to a list where each entry is a pair of an operation and a list of component specifiers.
+     ;; Up until ASDF 2.26.9, there used to be two kinds of dependencies:
+     ;; in-order-to and do-first, each stored in its own slot. Now there is only in-order-to.
+     ;; in-order-to used to represent things that modify the filesystem (such as compiling a fasl)
+     ;; and do-first things that modify the current image (such as loading a fasl).
+     ;; These are now unified because we now correctly propagate timestamps between dependencies.
+     ;; Happily, no one seems to have used do-first too much (especially since until ASDF 2.017,
+     ;; anything you specified was overridden by ASDF itself anyway), but the name in-order-to remains.
+     ;; The names are bad, but they have been the official API since Dan Barlow's ASDF 1.52!
+     ;; LispWorks's defsystem has caused-by and requires for in-order-to and do-first respectively.
+     ;; Maybe rename the slots in ASDF? But that's not very backward-compatible.
+     ;; See our ASDF 2 paper for more complete explanations.
+     (in-order-to :initform nil :initarg :in-order-to
+                  :accessor component-in-order-to)
+     ;; methods defined using the "inline" style inside a defsystem form:
+     ;; need to store them somewhere so we can delete them when the system
+     ;; is re-evaluated.
+     (inline-methods :accessor component-inline-methods :initform nil) ;; OBSOLETE! DELETE THIS IF NO ONE USES.
+     ;; ASDF4: rename it from relative-pathname to specified-pathname. It need not be relative.
+     ;; There is no initform and no direct accessor for this specified pathname,
+     ;; so we only access the information through appropriate methods, after it has been processed.
+     ;; Unhappily, some braindead systems directly access the slot. Make them stop before ASDF4.
+     (relative-pathname :initarg :pathname)
+     ;; The absolute-pathname is computed based on relative-pathname and parent pathname.
+     ;; The slot is but a cache used by component-pathname.
+     (absolute-pathname)
+     (operation-times :initform (make-hash-table)
+                      :accessor component-operation-times)
+     (around-compile :initarg :around-compile)
+     ;; Properties are for backward-compatibility with ASDF2 only. DO NOT USE!
+     (properties :accessor component-properties :initarg :properties
+                 :initform nil)
+     (%encoding :accessor %component-encoding :initform nil :initarg :encoding)
+     ;; For backward-compatibility, this slot is part of component rather than of child-component. ASDF4: stop it.
+     (parent :initarg :parent :initform nil :reader component-parent)
+     (build-operation
+      :initarg :build-operation :initform nil :reader component-build-operation)))
+
+  (defun component-find-path (component)
+    (check-type component (or null component))
+    (reverse
+     (loop :for c = component :then (component-parent c)
+           :while c :collect (component-name c))))
+
+  (defmethod print-object ((c component) stream)
+    (print-unreadable-object (c stream :type t :identity nil)
+      (format stream "~{~S~^ ~}" (component-find-path c))))
+
+  (defmethod component-system ((component component))
+    (if-let (system (component-parent component))
+      (component-system system)
+      component)))
 
 
 ;;;; Component hierarchy within a system
 ;; The tree typically but not necessarily follows the filesystem hierarchy.
+(with-upgradability ()
+  (defclass child-component (component) ())
 
-(defclass child-component (component) ())
+  (defclass file-component (child-component)
+    ((type :accessor file-type :initarg :type))) ; no default
+  (defclass source-file (file-component)
+    ((type :initform nil))) ;; NB: many systems have come to rely on this default.
+  (defclass c-source-file (source-file)
+    ((type :initform "c")))
+  (defclass java-source-file (source-file)
+    ((type :initform "java")))
+  (defclass static-file (source-file)
+    ((type :initform nil)))
+  (defclass doc-file (static-file) ())
+  (defclass html-file (doc-file)
+    ((type :initform "html")))
+
+  (defclass parent-component (component)
+    ((children
+      :initform nil
+      :initarg :components
+      :reader module-components ; backward-compatibility
+      :accessor component-children)
+     (children-by-name
+      :reader module-components-by-name ; backward-compatibility
+      :accessor component-children-by-name)
+     (default-component-class
+      :initform nil
+      :initarg :default-component-class
+      :accessor module-default-component-class))))
 
-(defclass file-component (child-component)
-  ((type :accessor file-type :initarg :type))) ; no default
-(defclass source-file (file-component)
-  ((type :initform nil))) ;; NB: many systems have come to rely on this default.
-(defclass c-source-file (source-file)
-  ((type :initform "c")))
-(defclass java-source-file (source-file)
-  ((type :initform "java")))
-(defclass static-file (source-file)
-  ((type :initform nil)))
-(defclass doc-file (static-file) ())
-(defclass html-file (doc-file)
-  ((type :initform "html")))
-
-(defclass parent-component (component)
-  ((children
-    :initform nil
-    :initarg :components
-    :reader module-components ; backward-compatibility
-    :accessor component-children)
-   (children-by-name
-    :reader module-components-by-name ; backward-compatibility
-    :accessor component-children-by-name)
-   (default-component-class
-    :initform nil
-    :initarg :default-component-class
-    :accessor module-default-component-class)))
-
-(eval-when (:compile-toplevel :load-toplevel :execute)
-  (defun* compute-children-by-name (parent &key only-if-needed-p)
+(with-upgradability ()
+  (defun compute-children-by-name (parent &key only-if-needed-p)
     (unless (and only-if-needed-p (slot-boundp parent 'children-by-name))
       (let ((hash (make-hash-table :test 'equal)))
         (setf (component-children-by-name parent) hash)
@@ -5139,7 +5390,7 @@
                   (setf (gethash name hash) c))
         hash))))
 
-(when-upgrade (:when (find-class 'module nil))
+(when-upgrading (:when (find-class 'module nil))
   (defmethod reinitialize-instance :after ((m module) &rest initargs &key)
     (declare (ignorable m initargs)) (values))
   (defmethod update-instance-for-redefined-class :after
@@ -5152,96 +5403,98 @@
                 (getf plist 'components)))
       (compute-children-by-name m))))
 
-(defclass module (child-component parent-component)
-  ())
+(with-upgradability ()
+  (defclass module (child-component parent-component)
+    (#+clisp (components)))) ;; backward compatibility during upgrade only
 
 
 ;;;; component pathnames
-
-(defgeneric* (component-parent-pathname) (component))
-(defmethod component-parent-pathname (component)
-  (component-pathname (component-parent component)))
-
-(defmethod component-pathname ((component component))
-  (if (slot-boundp component 'absolute-pathname)
-      (slot-value component 'absolute-pathname)
-      (let ((pathname
-             (merge-pathnames*
-              (component-relative-pathname component)
-              (pathname-directory-pathname (component-parent-pathname component)))))
-        (unless (or (null pathname) (absolute-pathname-p pathname))
-          (error (compatfmt "~@<Invalid relative pathname ~S for component ~S~@:>")
-                 pathname (component-find-path component)))
-        (setf (slot-value component 'absolute-pathname) pathname)
-        pathname)))
-
-(defmethod component-relative-pathname ((component component))
-  ;; source-file-type is backward-compatibility with ASDF1;
-  ;; we ought to be able to extract this from the component alone with COMPONENT-TYPE.
-  ;; TODO: track who uses it, and have them not use it anymore.
-  (parse-unix-namestring
-   (or (and (slot-boundp component 'relative-pathname)
-            (slot-value component 'relative-pathname))
-       (component-name component))
-   :want-relative t
-   :type (source-file-type component (component-system component))
-   :defaults (component-parent-pathname component)))
-
-(defmethod source-file-type ((component parent-component) system)
-  (declare (ignorable component system))
-  :directory)
-
-(defmethod source-file-type ((component file-component) system)
-  (declare (ignorable system))
-  (file-type component))
+(with-upgradability ()
+  (defgeneric* (component-parent-pathname) (component))
+  (defmethod component-parent-pathname (component)
+    (component-pathname (component-parent component)))
+
+  (defmethod component-pathname ((component component))
+    (if (slot-boundp component 'absolute-pathname)
+        (slot-value component 'absolute-pathname)
+        (let ((pathname
+                (merge-pathnames*
+                 (component-relative-pathname component)
+                 (pathname-directory-pathname (component-parent-pathname component)))))
+          (unless (or (null pathname) (absolute-pathname-p pathname))
+            (error (compatfmt "~@<Invalid relative pathname ~S for component ~S~@:>")
+                   pathname (component-find-path component)))
+          (setf (slot-value component 'absolute-pathname) pathname)
+          pathname)))
+
+  (defmethod component-relative-pathname ((component component))
+    ;; source-file-type is backward-compatibility with ASDF1;
+    ;; we ought to be able to extract this from the component alone with COMPONENT-TYPE.
+    ;; TODO: track who uses it, and have them not use it anymore.
+    (parse-unix-namestring
+     (or (and (slot-boundp component 'relative-pathname)
+              (slot-value component 'relative-pathname))
+         (component-name component))
+     :want-relative t
+     :type (source-file-type component (component-system component))
+     :defaults (component-parent-pathname component)))
+
+  (defmethod source-file-type ((component parent-component) system)
+    (declare (ignorable component system))
+    :directory)
+
+  (defmethod source-file-type ((component file-component) system)
+    (declare (ignorable system))
+    (file-type component)))
 
 
 ;;;; Encodings
+(with-upgradability ()
+  (defmethod component-encoding ((c component))
+    (or (loop :for x = c :then (component-parent x)
+              :while x :thereis (%component-encoding x))
+        (detect-encoding (component-pathname c))))
 
-(defmethod component-encoding ((c component))
-  (or (loop :for x = c :then (component-parent x)
-        :while x :thereis (%component-encoding x))
-      (detect-encoding (component-pathname c))))
-
-(defmethod component-external-format ((c component))
-  (encoding-external-format (component-encoding c)))
+  (defmethod component-external-format ((c component))
+    (encoding-external-format (component-encoding c))))
 
 
 ;;;; around-compile-hook
-
-(defgeneric* around-compile-hook (component))
-(defmethod around-compile-hook ((c component))
-  (cond
-    ((slot-boundp c 'around-compile)
-     (slot-value c 'around-compile))
-    ((component-parent c)
-     (around-compile-hook (component-parent c)))))
+(with-upgradability ()
+  (defgeneric around-compile-hook (component))
+  (defmethod around-compile-hook ((c component))
+    (cond
+      ((slot-boundp c 'around-compile)
+       (slot-value c 'around-compile))
+      ((component-parent c)
+       (around-compile-hook (component-parent c))))))
 
 
 ;;;; version-satisfies
+(with-upgradability ()
+  (defmethod version-satisfies ((c component) version)
+    (unless (and version (slot-boundp c 'version))
+      (when version
+        (warn "Requested version ~S but component ~S has no version" version c))
+      (return-from version-satisfies t))
+    (version-satisfies (component-version c) version))
 
-(defmethod version-satisfies ((c component) version)
-  (unless (and version (slot-boundp c 'version))
-    (when version
-      (warn "Requested version ~S but component ~S has no version" version c))
-    (return-from version-satisfies t))
-  (version-satisfies (component-version c) version))
-
-(defmethod version-satisfies ((cver string) version)
-  (version-compatible-p cver version))
+  (defmethod version-satisfies ((cver string) version)
+    (version-compatible-p cver version)))
 
 
 ;;; all sub-components (of a given type)
+(with-upgradability ()
+  (defun sub-components (component &key (type t))
+    (while-collecting (c)
+      (labels ((recurse (x)
+                 (when (if-let (it (component-if-feature x)) (featurep it) t)
+                   (when (typep x type)
+                     (c x))
+                   (when (typep x 'parent-component)
+                     (map () #'recurse (component-children x))))))
+        (recurse component)))))
 
-(defun* sub-components (component &key (type t))
-  (while-collecting (c)
-    (labels ((recurse (x)
-               (when (if-let (it (component-if-feature x)) (featurep it) t)
-                 (when (typep x type)
-                   (c x))
-                 (when (typep x 'parent-component)
-                   (map () #'recurse (component-children x))))))
-      (recurse component))))
 ;;;; -------------------------------------------------------------------------
 ;;;; Systems
 
@@ -5257,83 +5510,102 @@
    #:system-defsystem-depends-on
    #:component-build-pathname #:build-pathname
    #:component-entry-point #:entry-point
+   #:homepage #:system-homepage
+   #:bug-tracker #:system-bug-tracker
+   #:mailto #:system-mailto
+   #:long-name #:system-long-name
+   #:source-control #:system-source-control
    #:find-system #:builtin-system-p)) ;; forward-reference, defined in find-system
 (in-package :asdf/system)
 
-(defgeneric* (find-system) (system &optional error-p))
-(defgeneric* (system-source-file) (system)
-  (:documentation "Return the source file in which system is defined."))
-(defgeneric* component-build-pathname (component))
-
-(defgeneric* component-entry-point (component))
-(defmethod component-entry-point ((c component))
-  (declare (ignorable c))
-  nil)
+(with-upgradability ()
+  (defgeneric* (find-system) (system &optional error-p))
+  (defgeneric* (system-source-file) (system)
+    (:documentation "Return the source file in which system is defined."))
+  (defgeneric component-build-pathname (component))
+
+  (defgeneric component-entry-point (component))
+  (defmethod component-entry-point ((c component))
+    (declare (ignorable c))
+    nil))
 
 
 ;;;; The system class
 
-(defclass proto-system () ; slots to keep when resetting a system
-  ;; To preserve identity for all objects, we'd need keep the components slots
-  ;; but also to modify parse-component-form to reset the recycled objects.
-  ((name) (source-file) #|(children) (children-by-names)|#))
-
-(defclass system (module proto-system)
-  ;; Backward-compatibility: inherit from module. ASDF4: only inherit from parent-component.
-  (;; {,long-}description is now inherited from component, but we add the legacy accessors
-   (description :accessor system-description)
-   (long-description :accessor system-long-description)
-   (author :accessor system-author :initarg :author)
-   (maintainer :accessor system-maintainer :initarg :maintainer)
-   (licence :accessor system-licence :initarg :licence
-            :accessor system-license :initarg :license)
-   (builtin-system-p :accessor builtin-system-p :initform nil :initarg :builtin-system-p)
-   (build-pathname
-    :initform nil :initarg :build-pathname :accessor component-build-pathname)
-   (entry-point
-    :initform nil :initarg :entry-point :accessor component-entry-point)
-   (source-file :initform nil :initarg :source-file :accessor system-source-file)
-   (defsystem-depends-on :reader system-defsystem-depends-on :initarg :defsystem-depends-on)))
-
-(defun* reset-system (system &rest keys &key &allow-other-keys)
-  (change-class (change-class system 'proto-system) 'system)
-  (apply 'reinitialize-instance system keys))
+(with-upgradability ()
+  (defclass proto-system () ; slots to keep when resetting a system
+    ;; To preserve identity for all objects, we'd need keep the components slots
+    ;; but also to modify parse-component-form to reset the recycled objects.
+    ((name) (source-file) #|(children) (children-by-names)|#))
+
+  (defclass system (module proto-system)
+    ;; Backward-compatibility: inherit from module. ASDF4: only inherit from parent-component.
+    (;; {,long-}description is now inherited from component, but we add the legacy accessors
+     (description :accessor system-description)
+     (long-description :accessor system-long-description)
+     (author :accessor system-author :initarg :author :initform nil)
+     (maintainer :accessor system-maintainer :initarg :maintainer :initform nil)
+     (licence :accessor system-licence :initarg :licence
+              :accessor system-license :initarg :license :initform nil)
+     (homepage :accessor system-homepage :initarg :homepage :initform nil)
+     (bug-tracker :accessor system-bug-tracker :initarg :bug-tracker :initform nil)
+     (mailto :accessor system-mailto :initarg :mailto :initform nil)
+     (long-name :accessor system-long-name :initarg :long-name :initform nil)
+     ;; Conventions for this slot aren't clear yet as of ASDF 2.27, but whenever they are, they will be enforced.
+     ;; I'm introducing the slot before the conventions are set for maximum compatibility.
+     (source-control :accessor system-source-control :initarg :source-control :initform nil)
+     (builtin-system-p :accessor builtin-system-p :initform nil :initarg :builtin-system-p)
+     (build-pathname
+      :initform nil :initarg :build-pathname :accessor component-build-pathname)
+     (entry-point
+      :initform nil :initarg :entry-point :accessor component-entry-point)
+     (source-file :initform nil :initarg :source-file :accessor system-source-file)
+     (defsystem-depends-on :reader system-defsystem-depends-on :initarg :defsystem-depends-on)))
+
+  (defun reset-system (system &rest keys &key &allow-other-keys)
+    (change-class (change-class system 'proto-system) 'system)
+    (apply 'reinitialize-instance system keys)))
 
 
 ;;;; Pathnames
 
-(defmethod system-source-file ((system-name string))
-  (system-source-file (find-system system-name)))
-(defmethod system-source-file ((system-name symbol))
-  (system-source-file (find-system system-name)))
+(with-upgradability ()
+  (defmethod system-source-file ((system-name string))
+    (system-source-file (find-system system-name)))
+  (defmethod system-source-file ((system-name symbol))
+    (system-source-file (find-system system-name)))
 
-(defun* system-source-directory (system-designator)
-  "Return a pathname object corresponding to the directory
+  (defun system-source-directory (system-designator)
+    "Return a pathname object corresponding to the directory
 in which the system specification (.asd file) is located."
-  (pathname-directory-pathname (system-source-file system-designator)))
+    (pathname-directory-pathname (system-source-file system-designator)))
 
-(defun* (system-relative-pathname) (system name &key type)
-  (subpathname (system-source-directory system) name :type type))
+  (defun (system-relative-pathname) (system name &key type)
+    (subpathname (system-source-directory system) name :type type))
+
+  (defmethod component-pathname ((system system))
+    (let ((pathname (or (call-next-method) (system-source-directory system))))
+      (unless (and (slot-boundp system 'relative-pathname) ;; backward-compatibility with ASDF1-age
+                   (slot-value system 'relative-pathname)) ;; systems that directly access this slot.
+        (setf (slot-value system 'relative-pathname) pathname))
+      pathname))
+
+  (defmethod component-relative-pathname ((system system))
+    (parse-unix-namestring
+     (and (slot-boundp system 'relative-pathname)
+          (slot-value system 'relative-pathname))
+     :want-relative t
+     :type :directory
+     :ensure-absolute t
+     :defaults (system-source-directory system)))
+
+  (defmethod component-parent-pathname ((system system))
+    (system-source-directory system))
+
+  (defmethod component-build-pathname ((c component))
+    (declare (ignorable c))
+    nil))
 
-(defmethod component-pathname ((system system))
-  (or (call-next-method)
-      (system-source-directory system)))
-
-(defmethod component-relative-pathname ((system system))
-  (parse-unix-namestring
-   (and (slot-boundp system 'relative-pathname)
-        (slot-value system 'relative-pathname))
-   :want-relative t
-   :type :directory
-   :ensure-absolute t
-   :defaults (system-source-directory system)))
-
-(defmethod component-parent-pathname ((system system))
-  (system-source-directory system))
-
-(defmethod component-build-pathname ((c component))
-  (declare (ignorable c))
-  nil)
 ;;;; -------------------------------------------------------------------------
 ;;;; Stamp cache
 
@@ -5349,42 +5621,45 @@
 ;; * fewer accesses to the filesystem
 ;; * the ability to test with fake timestamps, without touching files
 
-(defvar *asdf-cache* nil)
+(with-upgradability ()
+  (defvar *asdf-cache* nil)
 
-(defun set-asdf-cache-entry (key value-list)
-  (apply 'values
-         (if *asdf-cache*
-             (setf (gethash key *asdf-cache*) value-list)
-             value-list)))
-
-(defun consult-asdf-cache (key thunk)
-  (if *asdf-cache*
-      (multiple-value-bind (results foundp) (gethash key *asdf-cache*)
-        (if foundp
-            (apply 'values results)
-            (set-asdf-cache-entry key (multiple-value-list (funcall thunk)))))
-      (funcall thunk)))
+  (defun set-asdf-cache-entry (key value-list)
+    (apply 'values
+           (if *asdf-cache*
+               (setf (gethash key *asdf-cache*) value-list)
+               value-list)))
+
+  (defun consult-asdf-cache (key thunk)
+    (if *asdf-cache*
+        (multiple-value-bind (results foundp) (gethash key *asdf-cache*)
+          (if foundp
+              (apply 'values results)
+              (set-asdf-cache-entry key (multiple-value-list (funcall thunk)))))
+        (funcall thunk)))
+
+  (defmacro do-asdf-cache (key &body body)
+    `(consult-asdf-cache ,key #'(lambda () , at body)))
+
+  (defun call-with-asdf-cache (thunk &key override)
+    (if (and *asdf-cache* (not override))
+        (funcall thunk)
+        (let ((*asdf-cache* (make-hash-table :test 'equal)))
+          (funcall thunk))))
+
+  (defmacro with-asdf-cache ((&key override) &body body)
+    `(call-with-asdf-cache #'(lambda () , at body) :override ,override))
 
-(defmacro do-asdf-cache (key &body body)
-  `(consult-asdf-cache ,key #'(lambda () , at body)))
+  (defun compute-file-stamp (file)
+    (safe-file-write-date file))
 
-(defun call-with-asdf-cache (thunk &key override)
-  (if (and *asdf-cache* (not override))
-      (funcall thunk)
-      (let ((*asdf-cache* (make-hash-table :test 'equal)))
-        (funcall thunk))))
-
-(defmacro with-asdf-cache ((&key override) &body body)
-  `(call-with-asdf-cache #'(lambda () , at body) :override ,override))
+  (defun register-file-stamp (file &optional (stamp (compute-file-stamp file)))
+    (set-asdf-cache-entry `(get-file-stamp ,file) (list stamp)))
 
-(defun compute-file-stamp (file)
-  (safe-file-write-date file))
+  (defun get-file-stamp (file)
+    (do-asdf-cache `(get-file-stamp ,file) (compute-file-stamp file))))
 
-(defun register-file-stamp (file &optional (stamp (compute-file-stamp file)))
-  (set-asdf-cache-entry `(get-file-stamp ,file) (list stamp)))
 
-(defun get-file-stamp (file)
-  (do-asdf-cache `(get-file-stamp ,file) (compute-file-stamp file)))
 ;;;; -------------------------------------------------------------------------
 ;;;; Finding systems
 
@@ -5405,128 +5680,137 @@
    #:find-system-if-being-defined #:*systems-being-defined*
    #:contrib-sysdef-search #:sysdef-find-asdf ;; backward compatibility symbols, functions removed
    #:system-find-preloaded-system #:register-preloaded-system #:*preloaded-systems*
-   #:make-defined-systems-table #:*defined-systems*
+   #:clear-defined-systems #:*defined-systems*
    ;; defined in source-registry, but specially mentioned here:
    #:initialize-source-registry #:sysdef-source-registry-search))
 (in-package :asdf/find-system)
 
-(declaim (ftype (function (&optional t) t) initialize-source-registry)) ; forward reference
+(with-upgradability ()
+  (declaim (ftype (function (&optional t) t) initialize-source-registry)) ; forward reference
 
-(define-condition system-definition-error (error) ()
-  ;; [this use of :report should be redundant, but unfortunately it's not.
-  ;; cmucl's lisp::output-instance prefers the kernel:slot-class-print-function
-  ;; over print-object; this is always conditions::%print-condition for
-  ;; condition objects, which in turn does inheritance of :report options at
-  ;; run-time.  fortunately, inheritance means we only need this kludge here in
-  ;; order to fix all conditions that build on it.  -- rgr, 28-Jul-02.]
-  #+cmu (:report print-object))
-
-(define-condition missing-component (system-definition-error)
-  ((requires :initform "(unnamed)" :reader missing-requires :initarg :requires)
-   (parent :initform nil :reader missing-parent :initarg :parent)))
-
-(define-condition formatted-system-definition-error (system-definition-error)
-  ((format-control :initarg :format-control :reader format-control)
-   (format-arguments :initarg :format-arguments :reader format-arguments))
-  (:report (lambda (c s)
+  (define-condition system-definition-error (error) ()
+    ;; [this use of :report should be redundant, but unfortunately it's not.
+    ;; cmucl's lisp::output-instance prefers the kernel:slot-class-print-function
+    ;; over print-object; this is always conditions::%print-condition for
+    ;; condition objects, which in turn does inheritance of :report options at
+    ;; run-time.  fortunately, inheritance means we only need this kludge here in
+    ;; order to fix all conditions that build on it.  -- rgr, 28-Jul-02.]
+    #+cmu (:report print-object))
+
+  (define-condition missing-component (system-definition-error)
+    ((requires :initform "(unnamed)" :reader missing-requires :initarg :requires)
+     (parent :initform nil :reader missing-parent :initarg :parent)))
+
+  (define-condition formatted-system-definition-error (system-definition-error)
+    ((format-control :initarg :format-control :reader format-control)
+     (format-arguments :initarg :format-arguments :reader format-arguments))
+    (:report (lambda (c s)
                (apply 'format s (format-control c) (format-arguments c)))))
 
-(define-condition load-system-definition-error (system-definition-error)
-  ((name :initarg :name :reader error-name)
-   (pathname :initarg :pathname :reader error-pathname)
-   (condition :initarg :condition :reader error-condition))
-  (:report (lambda (c s)
-             (format s (compatfmt "~@<Error while trying to load definition for system ~A from pathname ~A: ~3i~_~A~@:>")
-                     (error-name c) (error-pathname c) (error-condition c)))))
-
-(defun* sysdef-error (format &rest arguments)
-  (error 'formatted-system-definition-error :format-control
-         format :format-arguments arguments))
-
-(defun* make-defined-systems-table ()
-  (make-hash-table :test 'equal))
+  (define-condition load-system-definition-error (system-definition-error)
+    ((name :initarg :name :reader error-name)
+     (pathname :initarg :pathname :reader error-pathname)
+     (condition :initarg :condition :reader error-condition))
+    (:report (lambda (c s)
+               (format s (compatfmt "~@<Error while trying to load definition for system ~A from pathname ~A: ~3i~_~A~@:>")
+                       (error-name c) (error-pathname c) (error-condition c)))))
+
+  (defun sysdef-error (format &rest arguments)
+    (error 'formatted-system-definition-error :format-control
+           format :format-arguments arguments))
+
+  (defun coerce-name (name)
+    (typecase name
+      (component (component-name name))
+      (symbol (string-downcase (symbol-name name)))
+      (string name)
+      (t (sysdef-error (compatfmt "~@<Invalid component designator: ~3i~_~A~@:>") name))))
+
+  (defun primary-system-name (name)
+    ;; When a system name has slashes, the file with defsystem is named by
+    ;; the first of the slash-separated components.
+    (first (split-string (coerce-name name) :separator "/")))
 
-(defvar *defined-systems* (make-defined-systems-table)
-  "This is a hash table whose keys are strings, being the
+  (defvar *defined-systems* (make-hash-table :test 'equal)
+    "This is a hash table whose keys are strings, being the
 names of the systems, and whose values are pairs, the first
 element of which is a universal-time indicating when the
 system definition was last updated, and the second element
 of which is a system object.")
 
-(defun* coerce-name (name)
-  (typecase name
-    (component (component-name name))
-    (symbol (string-downcase (symbol-name name)))
-    (string name)
-    (t (sysdef-error (compatfmt "~@<Invalid component designator: ~3i~_~A~@:>") name))))
-
-(defun* primary-system-name (name)
-  ;; When a system name has slashes, the file with defsystem is named by
-  ;; the first of the slash-separated components.
-  (first (split-string (coerce-name name) :separator "/")))
-
-(defun* system-registered-p (name)
-  (gethash (coerce-name name) *defined-systems*))
-
-(defun* registered-systems ()
-  (loop :for registered :being :the :hash-values :of *defined-systems*
-    :collect (coerce-name (cdr registered))))
-
-(defun* register-system (system)
-  (check-type system system)
-  (let ((name (component-name system)))
-    (check-type name string)
-    (asdf-message (compatfmt "~&~@<; ~@;Registering ~3i~_~A~@:>~%") system)
-    (unless (eq system (cdr (gethash name *defined-systems*)))
-      (setf (gethash name *defined-systems*)
-            (cons (if-let (file (ignore-errors (system-source-file system)))
-                    (get-file-stamp file))
-                  system)))))
+  (defun system-registered-p (name)
+    (gethash (coerce-name name) *defined-systems*))
+
+  (defun registered-systems ()
+    (loop :for registered :being :the :hash-values :of *defined-systems*
+          :collect (coerce-name (cdr registered))))
+
+  (defun register-system (system)
+    (check-type system system)
+    (let ((name (component-name system)))
+      (check-type name string)
+      (asdf-message (compatfmt "~&~@<; ~@;Registering ~3i~_~A~@:>~%") system)
+      (unless (eq system (cdr (gethash name *defined-systems*)))
+        (setf (gethash name *defined-systems*)
+              (cons (if-let (file (ignore-errors (system-source-file system)))
+                      (get-file-stamp file))
+                    system)))))
+
+  (defun clear-defined-systems ()
+    ;; Invalidate all systems but ASDF itself, if registered.
+    (let ((asdf (cdr (system-registered-p :asdf))))
+      (setf *defined-systems* (make-hash-table :test 'equal))
+      (when asdf
+        (setf (component-version asdf) *asdf-version*)
+        (register-system asdf)))
+    (values))
 
-(defun* clear-system (name)
-  "Clear the entry for a system in the database of systems previously loaded.
+  (register-hook-function '*post-upgrade-cleanup-hook* 'clear-defined-systems nil)
+
+  (defun clear-system (name)
+    "Clear the entry for a system in the database of systems previously loaded.
 Note that this does NOT in any way cause the code of the system to be unloaded."
-  ;; There is no "unload" operation in Common Lisp, and
-  ;; a general such operation cannot be portably written,
-  ;; considering how much CL relies on side-effects to global data structures.
-  (remhash (coerce-name name) *defined-systems*))
+    ;; There is no "unload" operation in Common Lisp, and
+    ;; a general such operation cannot be portably written,
+    ;; considering how much CL relies on side-effects to global data structures.
+    (remhash (coerce-name name) *defined-systems*))
 
-(defun* map-systems (fn)
-  "Apply FN to each defined system.
+  (defun map-systems (fn)
+    "Apply FN to each defined system.
 
 FN should be a function of one argument. It will be
 called with an object of type asdf:system."
-  (loop :for registered :being :the :hash-values :of *defined-systems*
-     :do (funcall fn (cdr registered))))
+    (loop :for registered :being :the :hash-values :of *defined-systems*
+          :do (funcall fn (cdr registered)))))
 
 ;;; for the sake of keeping things reasonably neat, we adopt a
 ;;; convention that functions in this list are prefixed SYSDEF-
+(with-upgradability ()
+  (defvar *system-definition-search-functions* '())
 
-(defvar *system-definition-search-functions* '())
-
-(defun cleanup-system-definition-search-functions ()
-  (setf *system-definition-search-functions*
-        (append
-         ;; Remove known-incompatible sysdef functions from old versions of asdf.
-         (remove-if #'(lambda (x) (member x '(contrib-sysdef-search sysdef-find-asdf)))
-                    *system-definition-search-functions*)
-         ;; Tuck our defaults at the end of the list if they were absent.
-         ;; This is imperfect, in case they were removed on purpose,
-         ;; but then it will be the responsibility of whoever does that
-         ;; to upgrade asdf before he does such a thing rather than after.
-         (remove-if #'(lambda (x) (member x *system-definition-search-functions*))
-                    '(sysdef-central-registry-search
-                      sysdef-source-registry-search
-                      sysdef-find-preloaded-systems)))))
-(cleanup-system-definition-search-functions)
-
-(defun* search-for-system-definition (system)
-  (some (let ((name (coerce-name system))) #'(lambda (x) (funcall x name)))
-        (cons 'find-system-if-being-defined
-              *system-definition-search-functions*)))
+  (defun cleanup-system-definition-search-functions ()
+    (setf *system-definition-search-functions*
+          (append
+           ;; Remove known-incompatible sysdef functions from old versions of asdf.
+           (remove-if #'(lambda (x) (member x '(contrib-sysdef-search sysdef-find-asdf)))
+                      *system-definition-search-functions*)
+           ;; Tuck our defaults at the end of the list if they were absent.
+           ;; This is imperfect, in case they were removed on purpose,
+           ;; but then it will be the responsibility of whoever does that
+           ;; to upgrade asdf before he does such a thing rather than after.
+           (remove-if #'(lambda (x) (member x *system-definition-search-functions*))
+                      '(sysdef-central-registry-search
+                        sysdef-source-registry-search
+                        sysdef-find-preloaded-systems)))))
+  (cleanup-system-definition-search-functions)
+
+  (defun search-for-system-definition (system)
+    (some (let ((name (coerce-name system))) #'(lambda (x) (funcall x name)))
+          (cons 'find-system-if-being-defined
+                *system-definition-search-functions*)))
 
-(defvar *central-registry* nil
-"A list of 'system directory designators' ASDF uses to find systems.
+  (defvar *central-registry* nil
+    "A list of 'system directory designators' ASDF uses to find systems.
 
 A 'system directory designator' is a pathname or an expression
 which evaluates to a pathname. For example:
@@ -5540,118 +5824,120 @@
 Going forward, we recommend new users should be using the source-registry.
 ")
 
-(defun* probe-asd (name defaults &key truename)
-  (block nil
-    (when (directory-pathname-p defaults)
-      (if-let (file (probe-file*
-                     (ensure-pathname-absolute
-                      (parse-unix-namestring name :type "asd")
-                      #'(lambda () (ensure-pathname-absolute defaults 'get-pathname-defaults nil))
-                      nil)
-                     :truename truename))
-        (return file))
-      #-(or clisp genera) ; clisp doesn't need it, plain genera doesn't have read-sequence(!)
-      (when (os-windows-p)
-        (let ((shortcut
-               (make-pathname
-                :defaults defaults :case :local
-                :name (strcat name ".asd")
-                :type "lnk")))
-          (when (probe-file* shortcut)
-            (let ((target (parse-windows-shortcut shortcut)))
-              (when target
-                (return (pathname target))))))))))
-
-(defun* sysdef-central-registry-search (system)
-  (let ((name (primary-system-name system))
-        (to-remove nil)
-        (to-replace nil))
+  (defun probe-asd (name defaults &key truename)
     (block nil
-      (unwind-protect
-           (dolist (dir *central-registry*)
-             (let ((defaults (eval dir))
-                   directorized)
-               (when defaults
-                 (cond ((directory-pathname-p defaults)
-                        (let* ((file (probe-asd name defaults :truename *resolve-symlinks*)))
-                          (when file
-                            (return file))))
-                       (t
-                        (restart-case
-                            (let* ((*print-circle* nil)
-                                   (message
-                                    (format nil
-                                            (compatfmt "~@<While searching for system ~S: ~3i~_~S evaluated to ~S which is not an absolute directory.~@:>")
-                                            system dir defaults)))
-                              (error message))
-                          (remove-entry-from-registry ()
-                            :report "Remove entry from *central-registry* and continue"
-                            (push dir to-remove))
-                          (coerce-entry-to-directory ()
-                            :test (lambda (c) (declare (ignore c))
-                                    (and (not (directory-pathname-p defaults))
-                                         (directory-pathname-p
-                                          (setf directorized
-                                                (ensure-directory-pathname defaults)))))
-                            :report (lambda (s)
-                                      (format s (compatfmt "~@<Coerce entry to ~a, replace ~a and continue.~@:>")
-                                              directorized dir))
-                            (push (cons dir directorized) to-replace))))))))
-        ;; cleanup
-        (dolist (dir to-remove)
-          (setf *central-registry* (remove dir *central-registry*)))
-        (dolist (pair to-replace)
-          (let* ((current (car pair))
-                 (new (cdr pair))
-                 (position (position current *central-registry*)))
-            (setf *central-registry*
-                  (append (subseq *central-registry* 0 position)
-                          (list new)
-                          (subseq *central-registry* (1+ position))))))))))
-
-(defmethod find-system ((name null) &optional (error-p t))
-  (declare (ignorable name))
-  (when error-p
-    (sysdef-error (compatfmt "~@<NIL is not a valid system name~@:>"))))
-
-(defmethod find-system (name &optional (error-p t))
-  (find-system (coerce-name name) error-p))
-
-(defvar *systems-being-defined* nil
-  "A hash-table of systems currently being defined keyed by name, or NIL")
-
-(defun* find-system-if-being-defined (name)
-  (when *systems-being-defined*
-    (gethash (coerce-name name) *systems-being-defined*)))
-
-(defun* call-with-system-definitions (thunk)
-  (if *systems-being-defined*
-      (call-with-asdf-cache thunk)
-      (let ((*systems-being-defined* (make-hash-table :test 'equal)))
-        (call-with-asdf-cache thunk))))
-
-(defmacro with-system-definitions ((&optional) &body body)
-  `(call-with-system-definitions #'(lambda () , at body)))
-
-(defun* load-asd (pathname &key name (external-format (encoding-external-format (detect-encoding pathname))))
-  ;; Tries to load system definition with canonical NAME from PATHNAME.
-  (with-system-definitions ()
-    (let ((*package* (find-package :asdf-user))
-          (*default-pathname-defaults*
-            ;; resolve logical-pathnames so they won't wreak havoc in parsing namestrings.
-            (pathname-directory-pathname (translate-logical-pathname pathname))))
-      (handler-bind
-          ((error #'(lambda (condition)
-                      (error 'load-system-definition-error
-                             :name name :pathname pathname
-                             :condition condition))))
-        (asdf-message (compatfmt "~&~@<; ~@;Loading system definition~@[ for ~A~] from ~A~@:>~%")
-                      name pathname)
-        (with-muffled-loader-conditions ()
-          (load* pathname :external-format external-format))))))
+      (when (directory-pathname-p defaults)
+        (if-let (file (probe-file*
+                       (ensure-absolute-pathname
+                        (parse-unix-namestring name :type "asd")
+                        #'(lambda () (ensure-absolute-pathname defaults 'get-pathname-defaults nil))
+                        nil)
+                       :truename truename))
+          (return file))
+        #-(or clisp genera) ; clisp doesn't need it, plain genera doesn't have read-sequence(!)
+        (when (os-windows-p)
+          (let ((shortcut
+                  (make-pathname
+                   :defaults defaults :case :local
+                   :name (strcat name ".asd")
+                   :type "lnk")))
+            (when (probe-file* shortcut)
+              (let ((target (parse-windows-shortcut shortcut)))
+                (when target
+                  (return (pathname target))))))))))
+
+  (defun sysdef-central-registry-search (system)
+    (let ((name (primary-system-name system))
+          (to-remove nil)
+          (to-replace nil))
+      (block nil
+        (unwind-protect
+             (dolist (dir *central-registry*)
+               (let ((defaults (eval dir))
+                     directorized)
+                 (when defaults
+                   (cond ((directory-pathname-p defaults)
+                          (let* ((file (probe-asd name defaults :truename *resolve-symlinks*)))
+                            (when file
+                              (return file))))
+                         (t
+                          (restart-case
+                              (let* ((*print-circle* nil)
+                                     (message
+                                       (format nil
+                                               (compatfmt "~@<While searching for system ~S: ~3i~_~S evaluated to ~S which is not an absolute directory.~@:>")
+                                               system dir defaults)))
+                                (error message))
+                            (remove-entry-from-registry ()
+                              :report "Remove entry from *central-registry* and continue"
+                              (push dir to-remove))
+                            (coerce-entry-to-directory ()
+                              :test (lambda (c) (declare (ignore c))
+                                      (and (not (directory-pathname-p defaults))
+                                           (directory-pathname-p
+                                            (setf directorized
+                                                  (ensure-directory-pathname defaults)))))
+                              :report (lambda (s)
+                                        (format s (compatfmt "~@<Coerce entry to ~a, replace ~a and continue.~@:>")
+                                                directorized dir))
+                              (push (cons dir directorized) to-replace))))))))
+          ;; cleanup
+          (dolist (dir to-remove)
+            (setf *central-registry* (remove dir *central-registry*)))
+          (dolist (pair to-replace)
+            (let* ((current (car pair))
+                   (new (cdr pair))
+                   (position (position current *central-registry*)))
+              (setf *central-registry*
+                    (append (subseq *central-registry* 0 position)
+                            (list new)
+                            (subseq *central-registry* (1+ position))))))))))
+
+  (defmethod find-system ((name null) &optional (error-p t))
+    (declare (ignorable name))
+    (when error-p
+      (sysdef-error (compatfmt "~@<NIL is not a valid system name~@:>"))))
+
+  (defmethod find-system (name &optional (error-p t))
+    (find-system (coerce-name name) error-p))
+
+  (defvar *systems-being-defined* nil
+    "A hash-table of systems currently being defined keyed by name, or NIL")
+
+  (defun find-system-if-being-defined (name)
+    (when *systems-being-defined*
+      (gethash (coerce-name name) *systems-being-defined*)))
+
+  (defun call-with-system-definitions (thunk)
+    (if *systems-being-defined*
+        (call-with-asdf-cache thunk)
+        (let ((*systems-being-defined* (make-hash-table :test 'equal)))
+          (call-with-asdf-cache thunk))))
+
+  (defmacro with-system-definitions ((&optional) &body body)
+    `(call-with-system-definitions #'(lambda () , at body)))
+
+  (defun load-asd (pathname &key name (external-format (encoding-external-format (detect-encoding pathname))))
+    ;; Tries to load system definition with canonical NAME from PATHNAME.
+    (with-system-definitions ()
+      (with-standard-io-syntax
+        (let ((*package* (find-package :asdf-user))
+              (*print-readably* nil)
+              (*default-pathname-defaults*
+                ;; resolve logical-pathnames so they won't wreak havoc in parsing namestrings.
+                (pathname-directory-pathname (translate-logical-pathname pathname))))
+          (handler-bind
+              ((error #'(lambda (condition)
+                          (error 'load-system-definition-error
+                                 :name name :pathname pathname
+                                 :condition condition))))
+            (asdf-message (compatfmt "~&~@<; ~@;Loading system definition~@[ for ~A~] from ~A~@:>~%")
+                          name pathname)
+            (with-muffled-loader-conditions ()
+              (load* pathname :external-format external-format)))))))
 
-(defun* locate-system (name)
-  "Given a system NAME designator, try to locate where to load the system from.
+  (defun locate-system (name)
+    "Given a system NAME designator, try to locate where to load the system from.
 Returns five values: FOUNDP FOUND-SYSTEM PATHNAME PREVIOUS PREVIOUS-TIME
 FOUNDP is true when a system was found,
 either a new unregistered one or a previously registered one.
@@ -5660,71 +5946,73 @@
 either associated with FOUND-SYSTEM, or with the PREVIOUS system.
 PREVIOUS when not null is a previously loaded SYSTEM object of same name.
 PREVIOUS-TIME when not null is the time at which the PREVIOUS system was loaded."
-  (let* ((name (coerce-name name))
-         (in-memory (system-registered-p name)) ; load from disk if absent or newer on disk
-         (previous (cdr in-memory))
-         (previous (and (typep previous 'system) previous))
-         (previous-time (car in-memory))
-         (found (search-for-system-definition name))
-         (found-system (and (typep found 'system) found))
-         (pathname (or (and (typep found '(or pathname string)) (pathname found))
-                       (and found-system (system-source-file found-system))
-                       (and previous (system-source-file previous))))
-         (pathname (ensure-pathname (resolve-symlinks* pathname) :want-absolute t))
-         (foundp (and (or found-system pathname previous) t)))
-    (check-type found (or null pathname system))
-    (values foundp found-system pathname previous previous-time)))
-
-(defmethod find-system ((name string) &optional (error-p t))
-  (with-system-definitions ()
-    (loop
-      (restart-case
-          (multiple-value-bind (foundp found-system pathname previous previous-time)
-              (locate-system name)
-            (assert (eq foundp (and (or found-system pathname previous) t)))
-            (let ((previous-pathname (and previous (system-source-file previous)))
-                  (system (or previous found-system)))
-              (when (and found-system (not previous))
-                (register-system found-system))
-              (when (and system pathname)
-                (setf (system-source-file system) pathname))
-              (when (and pathname
-                         (not (and previous
-                                   (or (pathname-equal pathname previous-pathname)
-                                       (and pathname previous-pathname
-                                            (pathname-equal
-                                             (translate-logical-pathname pathname)
-                                             (translate-logical-pathname previous-pathname))))
-                                   (stamp<= (get-file-stamp pathname) previous-time))))
-                ;; only load when it's a pathname that is different or has newer content
-                (load-asd pathname :name name)))
-            (let ((in-memory (system-registered-p name))) ; try again after loading from disk if needed
-              (return
-                (cond
-                  (in-memory
-                   (when pathname
-                     (setf (car in-memory) (get-file-stamp pathname)))
-                   (cdr in-memory))
-                  (error-p
-                   (error 'missing-component :requires name))))))
-        (reinitialize-source-registry-and-retry ()
-          :report (lambda (s)
-                    (format s (compatfmt "~@<Retry finding system ~A after reinitializing the source-registry.~@:>") name))
-          (initialize-source-registry))))))
-
-(defvar *preloaded-systems* (make-hash-table :test 'equal))
-
-(defun* sysdef-find-preloaded-systems (requested)
-  (let ((name (coerce-name requested)))
-    (multiple-value-bind (keys foundp) (gethash name *preloaded-systems*)
-      (when foundp
-        (apply 'make-instance 'system :name name :source-file (getf keys :source-file) keys)))))
+    (let* ((name (coerce-name name))
+           (in-memory (system-registered-p name)) ; load from disk if absent or newer on disk
+           (previous (cdr in-memory))
+           (previous (and (typep previous 'system) previous))
+           (previous-time (car in-memory))
+           (found (search-for-system-definition name))
+           (found-system (and (typep found 'system) found))
+           (pathname (or (and (typep found '(or pathname string)) (pathname found))
+                         (and found-system (system-source-file found-system))
+                         (and previous (system-source-file previous))))
+           (pathname (ensure-pathname (resolve-symlinks* pathname) :want-absolute t))
+           (foundp (and (or found-system pathname previous) t)))
+      (check-type found (or null pathname system))
+      (values foundp found-system pathname previous previous-time)))
+
+  (defmethod find-system ((name string) &optional (error-p t))
+    (with-system-definitions ()
+      (loop
+        (restart-case
+            (multiple-value-bind (foundp found-system pathname previous previous-time)
+                (locate-system name)
+              (assert (eq foundp (and (or found-system pathname previous) t)))
+              (let ((previous-pathname (and previous (system-source-file previous)))
+                    (system (or previous found-system)))
+                (when (and found-system (not previous))
+                  (register-system found-system))
+                (when (and system pathname)
+                  (setf (system-source-file system) pathname))
+                (when (and pathname
+                           (let ((stamp (get-file-stamp pathname)))
+                             (and stamp
+                                  (not (and previous
+                                            (or (pathname-equal pathname previous-pathname)
+                                                (and pathname previous-pathname
+                                                     (pathname-equal
+                                                      (translate-logical-pathname pathname)
+                                                      (translate-logical-pathname previous-pathname))))
+                                            (stamp<= stamp previous-time))))))
+                  ;; only load when it's a pathname that is different or has newer content
+                  (load-asd pathname :name name)))
+              (let ((in-memory (system-registered-p name))) ; try again after loading from disk if needed
+                (return
+                  (cond
+                    (in-memory
+                     (when pathname
+                       (setf (car in-memory) (get-file-stamp pathname)))
+                     (cdr in-memory))
+                    (error-p
+                     (error 'missing-component :requires name))))))
+          (reinitialize-source-registry-and-retry ()
+            :report (lambda (s)
+                      (format s (compatfmt "~@<Retry finding system ~A after reinitializing the source-registry.~@:>") name))
+            (initialize-source-registry))))))
+
+  (defvar *preloaded-systems* (make-hash-table :test 'equal))
+
+  (defun sysdef-find-preloaded-systems (requested)
+    (let ((name (coerce-name requested)))
+      (multiple-value-bind (keys foundp) (gethash name *preloaded-systems*)
+        (when foundp
+          (apply 'make-instance 'system :name name :source-file (getf keys :source-file) keys)))))
 
-(defun register-preloaded-system (system-name &rest keys)
-  (setf (gethash (coerce-name system-name) *preloaded-systems*) keys))
+  (defun register-preloaded-system (system-name &rest keys)
+    (setf (gethash (coerce-name system-name) *preloaded-systems*) keys))
 
-(register-preloaded-system "asdf")
-(register-preloaded-system "asdf-driver")
+  (register-preloaded-system "asdf" :version *asdf-version*)
+  (register-preloaded-system "asdf-driver" :version *asdf-version*))
 
 ;;;; -------------------------------------------------------------------------
 ;;;; Finding components
@@ -5746,113 +6034,115 @@
 
 ;;;; Missing component conditions
 
-(define-condition missing-component-of-version (missing-component)
-  ((version :initform nil :reader missing-version :initarg :version)))
-
-(define-condition missing-dependency (missing-component)
-  ((required-by :initarg :required-by :reader missing-required-by)))
-
-(defmethod print-object ((c missing-dependency) s)
-  (format s (compatfmt "~@<~A, required by ~A~@:>")
-          (call-next-method c nil) (missing-required-by c)))
-
-(define-condition missing-dependency-of-version (missing-dependency
-                                                 missing-component-of-version)
-  ())
-
-(defmethod print-object ((c missing-component) s)
-  (format s (compatfmt "~@<Component ~S not found~@[ in ~A~]~@:>")
-          (missing-requires c)
-          (when (missing-parent c)
-            (coerce-name (missing-parent c)))))
-
-(defmethod print-object ((c missing-component-of-version) s)
-  (format s (compatfmt "~@<Component ~S does not match version ~A~@[ in ~A~]~@:>")
-          (missing-requires c)
-          (missing-version c)
-          (when (missing-parent c)
-            (coerce-name (missing-parent c)))))
+(with-upgradability ()
+  (define-condition missing-component-of-version (missing-component)
+    ((version :initform nil :reader missing-version :initarg :version)))
+
+  (define-condition missing-dependency (missing-component)
+    ((required-by :initarg :required-by :reader missing-required-by)))
+
+  (defmethod print-object ((c missing-dependency) s)
+    (format s (compatfmt "~@<~A, required by ~A~@:>")
+            (call-next-method c nil) (missing-required-by c)))
+
+  (define-condition missing-dependency-of-version (missing-dependency
+                                                   missing-component-of-version)
+    ())
+
+  (defmethod print-object ((c missing-component) s)
+    (format s (compatfmt "~@<Component ~S not found~@[ in ~A~]~@:>")
+            (missing-requires c)
+            (when (missing-parent c)
+              (coerce-name (missing-parent c)))))
+
+  (defmethod print-object ((c missing-component-of-version) s)
+    (format s (compatfmt "~@<Component ~S does not match version ~A~@[ in ~A~]~@:>")
+            (missing-requires c)
+            (missing-version c)
+            (when (missing-parent c)
+              (coerce-name (missing-parent c))))))
 
 
 ;;;; Finding components
 
-(defgeneric* (find-component) (base path)
-  (:documentation "Find a component by resolving the PATH starting from BASE parent"))
-(defgeneric* resolve-dependency-combination (component combinator arguments))
-
-(defmethod find-component ((base string) path)
-  (let ((s (find-system base nil)))
-    (and s (find-component s path))))
+(with-upgradability ()
+  (defgeneric* (find-component) (base path)
+    (:documentation "Find a component by resolving the PATH starting from BASE parent"))
+  (defgeneric resolve-dependency-combination (component combinator arguments))
+
+  (defmethod find-component ((base string) path)
+    (let ((s (find-system base nil)))
+      (and s (find-component s path))))
 
-(defmethod find-component ((base symbol) path)
-  (cond
-    (base (find-component (coerce-name base) path))
-    (path (find-component path nil))
-    (t    nil)))
-
-(defmethod find-component ((base cons) path)
-  (find-component (car base) (cons (cdr base) path)))
-
-(defmethod find-component ((parent parent-component) (name string))
-  (compute-children-by-name parent :only-if-needed-p t) ;; SBCL may miss the u-i-f-r-c method!!!
-  (values (gethash name (component-children-by-name parent))))
-
-(defmethod find-component (base (name symbol))
-  (if name
-      (find-component base (coerce-name name))
-      base))
-
-(defmethod find-component ((c component) (name cons))
-  (find-component (find-component c (car name)) (cdr name)))
-
-(defmethod find-component (base (actual component))
-  (declare (ignorable base))
-  actual)
-
-(defun* resolve-dependency-name (component name &optional version)
-  (loop
-    (restart-case
-        (return
-          (let ((comp (find-component (component-parent component) name)))
-            (unless comp
-              (error 'missing-dependency
-                     :required-by component
-                     :requires name))
-            (when version
-              (unless (version-satisfies comp version)
-                (error 'missing-dependency-of-version
+  (defmethod find-component ((base symbol) path)
+    (cond
+      (base (find-component (coerce-name base) path))
+      (path (find-component path nil))
+      (t    nil)))
+
+  (defmethod find-component ((base cons) path)
+    (find-component (car base) (cons (cdr base) path)))
+
+  (defmethod find-component ((parent parent-component) (name string))
+    (compute-children-by-name parent :only-if-needed-p t) ;; SBCL may miss the u-i-f-r-c method!!!
+    (values (gethash name (component-children-by-name parent))))
+
+  (defmethod find-component (base (name symbol))
+    (if name
+        (find-component base (coerce-name name))
+        base))
+
+  (defmethod find-component ((c component) (name cons))
+    (find-component (find-component c (car name)) (cdr name)))
+
+  (defmethod find-component (base (actual component))
+    (declare (ignorable base))
+    actual)
+
+  (defun resolve-dependency-name (component name &optional version)
+    (loop
+      (restart-case
+          (return
+            (let ((comp (find-component (component-parent component) name)))
+              (unless comp
+                (error 'missing-dependency
                        :required-by component
-                       :version version
-                       :requires name)))
-            comp))
-      (retry ()
-        :report (lambda (s)
-                  (format s (compatfmt "~@<Retry loading ~3i~_~A.~@:>") name))
-        :test
-        (lambda (c)
-          (or (null c)
-              (and (typep c 'missing-dependency)
-                   (eq (missing-required-by c) component)
-                   (equal (missing-requires c) name))))))))
-
-(defun* resolve-dependency-spec (component dep-spec)
-  (let ((component (find-component () component)))
-    (if (atom dep-spec)
-        (resolve-dependency-name component dep-spec)
-        (resolve-dependency-combination component (car dep-spec) (cdr dep-spec)))))
-
-(defmethod resolve-dependency-combination (component combinator arguments)
-  (error (compatfmt "~@<Bad dependency ~S for ~S~@:>")
-         (cons combinator arguments) component))
-
-(defmethod resolve-dependency-combination (component (combinator (eql :feature)) arguments)
-  (declare (ignorable combinator))
-  (when (featurep (first arguments))
-    (resolve-dependency-spec component (second arguments))))
-
-(defmethod resolve-dependency-combination (component (combinator (eql :version)) arguments)
-  (declare (ignorable combinator)) ;; See https://bugs.launchpad.net/asdf/+bug/527788
-  (resolve-dependency-name component (first arguments) (second arguments)))
+                       :requires name))
+              (when version
+                (unless (version-satisfies comp version)
+                  (error 'missing-dependency-of-version
+                         :required-by component
+                         :version version
+                         :requires name)))
+              comp))
+        (retry ()
+          :report (lambda (s)
+                    (format s (compatfmt "~@<Retry loading ~3i~_~A.~@:>") name))
+          :test
+          (lambda (c)
+            (or (null c)
+                (and (typep c 'missing-dependency)
+                     (eq (missing-required-by c) component)
+                     (equal (missing-requires c) name))))))))
+
+  (defun resolve-dependency-spec (component dep-spec)
+    (let ((component (find-component () component)))
+      (if (atom dep-spec)
+          (resolve-dependency-name component dep-spec)
+          (resolve-dependency-combination component (car dep-spec) (cdr dep-spec)))))
+
+  (defmethod resolve-dependency-combination (component combinator arguments)
+    (error (compatfmt "~@<Bad dependency ~S for ~S~@:>")
+           (cons combinator arguments) component))
+
+  (defmethod resolve-dependency-combination (component (combinator (eql :feature)) arguments)
+    (declare (ignorable combinator))
+    (when (featurep (first arguments))
+      (resolve-dependency-spec component (second arguments))))
+
+  (defmethod resolve-dependency-combination (component (combinator (eql :version)) arguments)
+    (declare (ignorable combinator)) ;; See https://bugs.launchpad.net/asdf/+bug/527788
+    (resolve-dependency-name component (first arguments) (second arguments))))
 
 ;;;; -------------------------------------------------------------------------
 ;;;; Operations
@@ -5871,47 +6161,50 @@
 
 ;;; Operation Classes
 
-(when-upgrade (:when (find-class 'operation nil))
+(when-upgrading (:when (find-class 'operation nil))
   (defmethod shared-initialize :after ((o operation) slot-names &rest initargs &key)
     (declare (ignorable o slot-names initargs)) (values)))
 
-(defclass operation ()
-  ((original-initargs ;; for backward-compat -- used by GBBopen and swank (via operation-forced)
-    :initform nil :initarg :original-initargs :accessor operation-original-initargs)))
-
-(defmethod initialize-instance :after ((o operation) &rest initargs
-                                       &key force force-not system verbose &allow-other-keys)
-  (declare (ignorable force force-not system verbose))
-  (unless (slot-boundp o 'original-initargs)
-    (setf (operation-original-initargs o) initargs)))
-
-(defmethod print-object ((o operation) stream)
-  (print-unreadable-object (o stream :type t :identity nil)
-    (ignore-errors
-      (format stream "~{~S~^ ~}" (operation-original-initargs o)))))
+(with-upgradability ()
+  (defclass operation ()
+    ((original-initargs ;; for backward-compat -- used by GBBopen and swank (via operation-forced)
+      :initform nil :initarg :original-initargs :accessor operation-original-initargs)))
+
+  (defmethod initialize-instance :after ((o operation) &rest initargs
+                                         &key force force-not system verbose &allow-other-keys)
+    (declare (ignorable force force-not system verbose))
+    (unless (slot-boundp o 'original-initargs)
+      (setf (operation-original-initargs o) initargs)))
+
+  (defmethod print-object ((o operation) stream)
+    (print-unreadable-object (o stream :type t :identity nil)
+      (ignore-errors
+       (format stream "~{~S~^ ~}" (operation-original-initargs o))))))
 
 ;;; make-operation, find-operation
 
-(defparameter *operations* (make-hash-table :test 'equal))
-(defun* make-operation (operation-class &rest initargs)
-  (let ((key (cons operation-class initargs)))
-    (multiple-value-bind (operation foundp) (gethash key *operations*)
-    (if foundp operation
-        (setf (gethash key *operations*)
-              (apply 'make-instance operation-class initargs))))))
-
-(defgeneric* find-operation (context spec)
-  (:documentation "Find an operation by resolving the SPEC in the CONTEXT"))
-(defmethod find-operation (context (spec operation))
-  (declare (ignorable context))
-  spec)
-(defmethod find-operation (context (spec symbol))
-  (apply 'make-operation spec (operation-original-initargs context)))
-(defmethod operation-original-initargs ((context symbol))
-  (declare (ignorable context))
-  nil)
+(with-upgradability ()
+  (defparameter *operations* (make-hash-table :test 'equal))
+  (defun make-operation (operation-class &rest initargs)
+    (let ((key (cons operation-class initargs)))
+      (multiple-value-bind (operation foundp) (gethash key *operations*)
+        (if foundp operation
+            (setf (gethash key *operations*)
+                  (apply 'make-instance operation-class initargs))))))
+
+  (defgeneric find-operation (context spec)
+    (:documentation "Find an operation by resolving the SPEC in the CONTEXT"))
+  (defmethod find-operation (context (spec operation))
+    (declare (ignorable context))
+    spec)
+  (defmethod find-operation (context (spec symbol))
+    (apply 'make-operation spec (operation-original-initargs context)))
+  (defmethod operation-original-initargs ((context symbol))
+    (declare (ignorable context))
+    nil)
+
+  (defclass build-op (operation) ()))
 
-(defclass build-op (operation) ())
 
 ;;;; -------------------------------------------------------------------------
 ;;;; Actions
@@ -5921,7 +6214,6 @@
   (:recycle :asdf/action :asdf)
   (:use :asdf/common-lisp :asdf/driver :asdf/upgrade
    :asdf/component :asdf/system #:asdf/cache :asdf/find-system :asdf/find-component :asdf/operation)
-  (:intern #:stamp #:done-p)
   (:export
    #:action #:define-convenience-action-methods
    #:explain #:action-description
@@ -5932,77 +6224,81 @@
    #:component-operation-time #:mark-operation-done #:compute-action-stamp
    #:perform #:perform-with-restarts #:retry #:accept #:feature
    #:traverse-actions #:traverse-sub-actions #:required-components ;; in plan
-   #:action-path #:find-action))
+   #:action-path #:find-action #:stamp #:done-p))
 (in-package :asdf/action)
 
-(deftype action () '(cons operation component)) ;; a step to be performed while building the system
+(eval-when (#-lispworks :compile-toplevel :load-toplevel :execute)
+  (deftype action () '(cons operation component))) ;; a step to be performed while building
 
-(defgeneric* traverse-actions (actions &key &allow-other-keys))
-(defgeneric* traverse-sub-actions (operation component &key &allow-other-keys))
-(defgeneric* required-components (component &key &allow-other-keys))
-
-;;;; Reified representation for storage or debugging. Note: dropping original-initags
-(defun action-path (action)
-  (destructuring-bind (o . c) action (cons (type-of o) (component-find-path c))))
-(defun find-action (path)
-  (destructuring-bind (o . c) path (cons (make-operation o) (find-component () c))))
+(with-upgradability ()
+  (defgeneric traverse-actions (actions &key &allow-other-keys))
+  (defgeneric traverse-sub-actions (operation component &key &allow-other-keys))
+  (defgeneric required-components (component &key &allow-other-keys)))
+
+;;;; Reified representation for storage or debugging. Note: dropping original-initargs
+(with-upgradability ()
+  (defun action-path (action)
+    (destructuring-bind (o . c) action (cons (type-of o) (component-find-path c))))
+  (defun find-action (path)
+    (destructuring-bind (o . c) path (cons (make-operation o) (find-component () c)))))
 
 
 ;;;; Convenience methods
-(defmacro define-convenience-action-methods
-  (function (operation component &optional keyp)
-   &key if-no-operation if-no-component operation-initargs)
-  (let* ((rest (gensym "REST"))
-         (found (gensym "FOUND"))
-         (more-args (when keyp `(&rest ,rest &key &allow-other-keys))))
-    (flet ((next-method (o c)
-             (if keyp
-                 `(apply ',function ,o ,c ,rest)
-                 `(,function ,o ,c))))
-      `(progn
-         (defmethod ,function ((,operation symbol) ,component , at more-args)
-           (if ,operation
-               ,(next-method
-                 (if operation-initargs ;backward-compatibility with ASDF1's operate. Yuck.
-                     `(apply 'make-operation ,operation :original-initargs ,rest ,rest)
-                     `(make-operation ,operation))
-                 `(or (find-component () ,component) ,if-no-component))
-               ,if-no-operation))
-         (defmethod ,function ((,operation operation) ,component , at more-args)
-           (if (typep ,component 'component)
-               (error "No defined method for ~S on ~/asdf-action:format-action/"
-                      ',function (cons ,operation ,component))
-               (let ((,found (find-component () ,component)))
-                 (if ,found
-                     ,(next-method operation found)
-                     ,if-no-component))))))))
+(with-upgradability ()
+  (defmacro define-convenience-action-methods
+      (function (operation component &optional keyp)
+       &key if-no-operation if-no-component operation-initargs)
+    (let* ((rest (gensym "REST"))
+           (found (gensym "FOUND"))
+           (more-args (when keyp `(&rest ,rest &key &allow-other-keys))))
+      (flet ((next-method (o c)
+               (if keyp
+                   `(apply ',function ,o ,c ,rest)
+                   `(,function ,o ,c))))
+        `(progn
+           (defmethod ,function ((,operation symbol) ,component , at more-args)
+             (if ,operation
+                 ,(next-method
+                   (if operation-initargs ;backward-compatibility with ASDF1's operate. Yuck.
+                       `(apply 'make-operation ,operation :original-initargs ,rest ,rest)
+                       `(make-operation ,operation))
+                   `(or (find-component () ,component) ,if-no-component))
+                 ,if-no-operation))
+           (defmethod ,function ((,operation operation) ,component , at more-args)
+             (if (typep ,component 'component)
+                 (error "No defined method for ~S on ~/asdf-action:format-action/"
+                        ',function (cons ,operation ,component))
+                 (let ((,found (find-component () ,component)))
+                   (if ,found
+                       ,(next-method operation found)
+                       ,if-no-component)))))))))
 
 
 ;;;; self-description
-
-(defgeneric* action-description (operation component)
-  (:documentation "returns a phrase that describes performing this operation
+(with-upgradability ()
+  (defgeneric action-description (operation component)
+    (:documentation "returns a phrase that describes performing this operation
 on this component, e.g. \"loading /a/b/c\".
 You can put together sentences using this phrase."))
-(defmethod action-description (operation component)
-  (format nil (compatfmt "~@<~A on ~A~@:>")
-          (type-of operation) component))
-(defgeneric* (explain) (operation component))
-(defmethod explain ((o operation) (c component))
-  (asdf-message (compatfmt "~&~@<; ~@;~A~:>~%") (action-description o c)))
-(define-convenience-action-methods explain (operation component))
-
-(defun* format-action (stream action &optional colon-p at-sign-p)
-  (assert (null colon-p)) (assert (null at-sign-p))
-  (destructuring-bind (operation . component) action
-    (princ (action-description operation component) stream)))
+  (defmethod action-description (operation component)
+    (format nil (compatfmt "~@<~A on ~A~@:>")
+            (type-of operation) component))
+  (defgeneric* (explain) (operation component))
+  (defmethod explain ((o operation) (c component))
+    (asdf-message (compatfmt "~&~@<; ~@;~A~:>~%") (action-description o c)))
+  (define-convenience-action-methods explain (operation component))
+
+  (defun format-action (stream action &optional colon-p at-sign-p)
+    (assert (null colon-p)) (assert (null at-sign-p))
+    (destructuring-bind (operation . component) action
+      (princ (action-description operation component) stream))))
 
 
 ;;;; Dependencies
-
-(defgeneric* component-depends-on (operation component) ;; ASDF4: rename to component-dependencies
-  (:documentation
-   "Returns a list of dependencies needed by the component to perform
+(with-upgradability ()
+  (defgeneric component-depends-on (operation component) ;; ASDF4: rename to component-dependencies
+    (:documentation
+     "Returns a list of dependencies needed by the component to perform
     the operation.  A dependency has one of the following forms:
 
       (<operation> <component>*), where <operation> is a class
@@ -6016,120 +6312,122 @@
     Methods specialized on subclasses of existing component types
     should usually append the results of CALL-NEXT-METHOD to the
     list."))
-(defgeneric* component-self-dependencies (operation component))
-(define-convenience-action-methods component-depends-on (operation component))
-(define-convenience-action-methods component-self-dependencies (operation component))
-
-(defmethod component-depends-on ((o operation) (c component))
-  (cdr (assoc (type-of o) (component-in-order-to c)))) ; User-specified in-order dependencies
-
-(defmethod component-self-dependencies ((o operation) (c component))
-  ;; NB: result in the same format as component-depends-on
-  (loop* :for (o-spec . c-spec) :in (component-depends-on o c)
-         :unless (eq o-spec 'feature) ;; avoid the FEATURE "feature"
+  (defgeneric component-self-dependencies (operation component))
+  (define-convenience-action-methods component-depends-on (operation component))
+  (define-convenience-action-methods component-self-dependencies (operation component))
+
+  (defmethod component-depends-on ((o operation) (c component))
+    (cdr (assoc (type-of o) (component-in-order-to c)))) ; User-specified in-order dependencies
+
+  (defmethod component-self-dependencies ((o operation) (c component))
+    ;; NB: result in the same format as component-depends-on
+    (loop* :for (o-spec . c-spec) :in (component-depends-on o c)
+           :unless (eq o-spec 'feature) ;; avoid the FEATURE "feature"
            :when (find c c-spec :key #'(lambda (dep) (resolve-dependency-spec c dep)))
-             :collect (list o-spec c)))
+           :collect (list o-spec c))))
 
 ;;;; upward-operation, downward-operation
 ;; These together handle actions that propagate along the component hierarchy.
 ;; Downward operations like load-op or compile-op propagate down the hierarchy:
 ;; operation on a parent depends-on operation on its children.
 ;; By default, an operation propagates itself, but it may propagate another one instead.
-(defclass downward-operation (operation)
-  ((downward-operation
-    :initform nil :initarg :downward-operation :reader downward-operation)))
-(defmethod component-depends-on ((o downward-operation) (c parent-component))
-  `((,(or (downward-operation o) o) ,@(component-children c)) ,@(call-next-method)))
-;; Upward operations like prepare-op propagate up the component hierarchy:
-;; operation on a child depends-on operation on its parent.
-;; By default, an operation propagates itself, but it may propagate another one instead.
-(defclass upward-operation (operation)
-  ((upward-operation
-    :initform nil :initarg :downward-operation :reader upward-operation)))
-;; For backward-compatibility reasons, a system inherits from module and is a child-component
-;; so we must guard against this case. ASDF4: remove that.
-(defmethod component-depends-on ((o upward-operation) (c child-component))
-  `(,@(if-let (p (component-parent c))
-        `((,(or (upward-operation o) o) ,p))) ,@(call-next-method)))
-;; Sibling operations propagate to siblings in the component hierarchy:
-;; operation on a child depends-on operation on its parent.
-;; By default, an operation propagates itself, but it may propagate another one instead.
-(defclass sibling-operation (operation)
-  ((sibling-operation
-    :initform nil :initarg :sibling-operation :reader sibling-operation)))
-(defmethod component-depends-on ((o sibling-operation) (c component))
-  `((,(or (sibling-operation o) o)
-     ,@(loop :for dep :in (component-sibling-dependencies c)
-             :collect (resolve-dependency-spec c dep)))
-    ,@(call-next-method)))
+(with-upgradability ()
+  (defclass downward-operation (operation)
+    ((downward-operation
+      :initform nil :initarg :downward-operation :reader downward-operation)))
+  (defmethod component-depends-on ((o downward-operation) (c parent-component))
+    `((,(or (downward-operation o) o) ,@(component-children c)) ,@(call-next-method)))
+  ;; Upward operations like prepare-op propagate up the component hierarchy:
+  ;; operation on a child depends-on operation on its parent.
+  ;; By default, an operation propagates itself, but it may propagate another one instead.
+  (defclass upward-operation (operation)
+    ((upward-operation
+      :initform nil :initarg :downward-operation :reader upward-operation)))
+  ;; For backward-compatibility reasons, a system inherits from module and is a child-component
+  ;; so we must guard against this case. ASDF4: remove that.
+  (defmethod component-depends-on ((o upward-operation) (c child-component))
+    `(,@(if-let (p (component-parent c))
+          `((,(or (upward-operation o) o) ,p))) ,@(call-next-method)))
+  ;; Sibling operations propagate to siblings in the component hierarchy:
+  ;; operation on a child depends-on operation on its parent.
+  ;; By default, an operation propagates itself, but it may propagate another one instead.
+  (defclass sibling-operation (operation)
+    ((sibling-operation
+      :initform nil :initarg :sibling-operation :reader sibling-operation)))
+  (defmethod component-depends-on ((o sibling-operation) (c component))
+    `((,(or (sibling-operation o) o)
+       ,@(loop :for dep :in (component-sibling-dependencies c)
+               :collect (resolve-dependency-spec c dep)))
+      ,@(call-next-method))))
 
 
 ;;;; Inputs, Outputs, and invisible dependencies
-(defgeneric* (output-files) (operation component))
-(defgeneric* (input-files) (operation component))
-(defgeneric* (operation-done-p) (operation component)
-  (:documentation "Returns a boolean, which is NIL if the action is forced to be performed again"))
-(define-convenience-action-methods output-files (operation component))
-(define-convenience-action-methods input-files (operation component))
-(define-convenience-action-methods operation-done-p (operation component))
-
-(defmethod operation-done-p ((o operation) (c component))
-  (declare (ignorable o c))
-  t)
-
-(defmethod output-files :around (operation component)
-  "Translate output files, unless asked not to. Memoize the result."
-  operation component ;; hush genera, not convinced by declare ignorable(!)
-  (do-asdf-cache `(output-files ,operation ,component)
-    (values
-     (multiple-value-bind (pathnames fixedp) (call-next-method)
-       ;; 1- Make sure we have absolute pathnames
-       (let* ((directory (pathname-directory-pathname
-                          (component-pathname (find-component () component))))
-              (absolute-pathnames
-                (loop
-                  :for pathname :in pathnames
-                  :collect (ensure-pathname-absolute pathname directory))))
-         ;; 2- Translate those pathnames as required
-         (if fixedp
-             absolute-pathnames
-             (mapcar *output-translation-function* absolute-pathnames))))
-     t)))
-(defmethod output-files ((o operation) (c component))
-  (declare (ignorable o c))
-  nil)
-(defun* output-file (operation component)
-  "The unique output file of performing OPERATION on COMPONENT"
-  (let ((files (output-files operation component)))
-    (assert (length=n-p files 1))
-    (first files)))
-
-(defmethod input-files :around (operation component)
-  "memoize input files."
-  (do-asdf-cache `(input-files ,operation ,component)
-    (call-next-method)))
-
-(defmethod input-files ((o operation) (c parent-component))
-  (declare (ignorable o c))
-  nil)
-
-(defmethod input-files ((o operation) (c component))
-  (or (loop* :for (dep-o) :in (component-self-dependencies o c)
-             :append (or (output-files dep-o c) (input-files dep-o c)))
-      ;; no non-trivial previous operations needed?
-      ;; I guess we work with the original source file, then
-      (if-let ((pathname (component-pathname c)))
-        (and (file-pathname-p pathname) (list pathname)))))
-
+(with-upgradability ()
+  (defgeneric* (output-files) (operation component))
+  (defgeneric* (input-files) (operation component))
+  (defgeneric* (operation-done-p) (operation component)
+    (:documentation "Returns a boolean, which is NIL if the action is forced to be performed again"))
+  (define-convenience-action-methods output-files (operation component))
+  (define-convenience-action-methods input-files (operation component))
+  (define-convenience-action-methods operation-done-p (operation component))
+
+  (defmethod operation-done-p ((o operation) (c component))
+    (declare (ignorable o c))
+    t)
+
+  (defmethod output-files :around (operation component)
+    "Translate output files, unless asked not to. Memoize the result."
+    operation component ;; hush genera, not convinced by declare ignorable(!)
+    (do-asdf-cache `(output-files ,operation ,component)
+      (values
+       (multiple-value-bind (pathnames fixedp) (call-next-method)
+         ;; 1- Make sure we have absolute pathnames
+         (let* ((directory (pathname-directory-pathname
+                            (component-pathname (find-component () component))))
+                (absolute-pathnames
+                  (loop
+                    :for pathname :in pathnames
+                    :collect (ensure-absolute-pathname pathname directory))))
+           ;; 2- Translate those pathnames as required
+           (if fixedp
+               absolute-pathnames
+               (mapcar *output-translation-function* absolute-pathnames))))
+       t)))
+  (defmethod output-files ((o operation) (c component))
+    (declare (ignorable o c))
+    nil)
+  (defun output-file (operation component)
+    "The unique output file of performing OPERATION on COMPONENT"
+    (let ((files (output-files operation component)))
+      (assert (length=n-p files 1))
+      (first files)))
+
+  (defmethod input-files :around (operation component)
+    "memoize input files."
+    (do-asdf-cache `(input-files ,operation ,component)
+      (call-next-method)))
 
-;;;; Done performing
+  (defmethod input-files ((o operation) (c parent-component))
+    (declare (ignorable o c))
+    nil)
+
+  (defmethod input-files ((o operation) (c component))
+    (or (loop* :for (dep-o) :in (component-self-dependencies o c)
+               :append (or (output-files dep-o c) (input-files dep-o c)))
+        ;; no non-trivial previous operations needed?
+        ;; I guess we work with the original source file, then
+        (if-let ((pathname (component-pathname c)))
+          (and (file-pathname-p pathname) (list pathname))))))
 
-(defgeneric* component-operation-time (operation component)) ;; ASDF4: hide it behind plan-action-stamp
-(define-convenience-action-methods component-operation-time (operation component))
 
-(defgeneric* mark-operation-done (operation component)) ;; ASDF4: hide it behind (setf plan-action-stamp)
-(defgeneric* compute-action-stamp (plan operation component &key just-done)
-  (:documentation "Has this action been successfully done already,
+;;;; Done performing
+(with-upgradability ()
+  (defgeneric component-operation-time (operation component)) ;; ASDF4: hide it behind plan-action-stamp
+  (define-convenience-action-methods component-operation-time (operation component))
+
+  (defgeneric mark-operation-done (operation component)) ;; ASDF4: hide it behind (setf plan-action-stamp)
+  (defgeneric compute-action-stamp (plan operation component &key just-done)
+    (:documentation "Has this action been successfully done already,
 and at what known timestamp has it been done at or will it be done at?
 Takes two keywords JUST-DONE and PLAN:
 JUST-DONE is a boolean that is true if the action was just successfully performed,
@@ -6143,72 +6441,73 @@
 * a boolean DONE-P that indicates whether the action has actually been done,
   and both its output-files and its in-image side-effects are up to date."))
 
-(defclass action-status ()
-  ((stamp
-    :initarg :stamp :reader action-stamp
-    :documentation "STAMP associated with the ACTION if it has been completed already
+  (defclass action-status ()
+    ((stamp
+      :initarg :stamp :reader action-stamp
+      :documentation "STAMP associated with the ACTION if it has been completed already
 in some previous image, or T if it needs to be done.")
-   (done-p
-    :initarg :done-p :reader action-done-p
-    :documentation "a boolean, true iff the action was already done (before any planned action)."))
-  (:documentation "Status of an action"))
-
-(defmethod print-object ((status action-status) stream)
-  (print-unreadable-object (status stream :type t)
-    (with-slots (stamp done-p) status
-      (format stream "~@{~S~^ ~}" :stamp stamp :done-p done-p))))
-
-(defmethod component-operation-time ((o operation) (c component))
-  (gethash (type-of o) (component-operation-times c)))
-
-(defmethod mark-operation-done ((o operation) (c component))
-  (setf (gethash (type-of o) (component-operation-times c))
-        (compute-action-stamp nil o c :just-done t)))
+     (done-p
+      :initarg :done-p :reader action-done-p
+      :documentation "a boolean, true iff the action was already done (before any planned action)."))
+    (:documentation "Status of an action"))
+
+  (defmethod print-object ((status action-status) stream)
+    (print-unreadable-object (status stream :type t)
+      (with-slots (stamp done-p) status
+        (format stream "~@{~S~^ ~}" :stamp stamp :done-p done-p))))
+
+  (defmethod component-operation-time ((o operation) (c component))
+    (gethash (type-of o) (component-operation-times c)))
+
+  (defmethod mark-operation-done ((o operation) (c component))
+    (setf (gethash (type-of o) (component-operation-times c))
+          (compute-action-stamp nil o c :just-done t))))
 
 
 ;;;; Perform
-
-(defgeneric* (perform-with-restarts) (operation component))
-(defgeneric* (perform) (operation component))
-(define-convenience-action-methods perform (operation component))
-
-(defmethod perform :before ((o operation) (c component))
-  (ensure-all-directories-exist (output-files o c)))
-(defmethod perform :after ((o operation) (c component))
-  (mark-operation-done o c))
-(defmethod perform ((o operation) (c parent-component))
-  (declare (ignorable o c))
-  nil)
-(defmethod perform ((o operation) (c source-file))
-  (sysdef-error
-   (compatfmt "~@<Required method PERFORM not implemented for operation ~A, component ~A~@:>")
-   (class-of o) (class-of c)))
-
-(defmethod perform-with-restarts (operation component)
-  ;; TOO verbose, especially as the default. Add your own :before method
-  ;; to perform-with-restart or perform if you want that:
-  #|(when *asdf-verbose* (explain operation component))|#
-  (perform operation component))
-(defmethod perform-with-restarts :around (operation component)
-  (loop
-    (restart-case
-        (return (call-next-method))
-      (retry ()
-        :report
-        (lambda (s)
-          (format s (compatfmt "~@<Retry ~A.~@:>")
-                  (action-description operation component))))
-      (accept ()
-        :report
-        (lambda (s)
-          (format s (compatfmt "~@<Continue, treating ~A as having been successful.~@:>")
-                  (action-description operation component)))
-        (mark-operation-done operation component)
-        (return)))))
+(with-upgradability ()
+  (defgeneric* (perform-with-restarts) (operation component))
+  (defgeneric* (perform) (operation component))
+  (define-convenience-action-methods perform (operation component))
+
+  (defmethod perform :before ((o operation) (c component))
+    (ensure-all-directories-exist (output-files o c)))
+  (defmethod perform :after ((o operation) (c component))
+    (mark-operation-done o c))
+  (defmethod perform ((o operation) (c parent-component))
+    (declare (ignorable o c))
+    nil)
+  (defmethod perform ((o operation) (c source-file))
+    (sysdef-error
+     (compatfmt "~@<Required method PERFORM not implemented for operation ~A, component ~A~@:>")
+     (class-of o) (class-of c)))
+
+  (defmethod perform-with-restarts (operation component)
+    ;; TOO verbose, especially as the default. Add your own :before method
+    ;; to perform-with-restart or perform if you want that:
+    #|(explain operation component)|#
+    (perform operation component))
+  (defmethod perform-with-restarts :around (operation component)
+    (loop
+      (restart-case
+          (return (call-next-method))
+        (retry ()
+          :report
+          (lambda (s)
+            (format s (compatfmt "~@<Retry ~A.~@:>")
+                    (action-description operation component))))
+        (accept ()
+          :report
+          (lambda (s)
+            (format s (compatfmt "~@<Continue, treating ~A as having been successful.~@:>")
+                    (action-description operation component)))
+          (mark-operation-done operation component)
+          (return))))))
 
 ;;; Generic build operation
-(defmethod component-depends-on ((o build-op) (c component))
-  `((,(or (component-build-operation c) 'load-op) ,c)))
+(with-upgradability ()
+  (defmethod component-depends-on ((o build-op) (c component))
+    `((,(or (component-build-operation c) 'load-op) ,c))))
 
 ;;;; -------------------------------------------------------------------------
 ;;;; Actions to build Common Lisp software
@@ -6217,249 +6516,256 @@
   (:recycle :asdf/lisp-action :asdf)
   (:intern #:proclamations #:flags)
   (:use :asdf/common-lisp :asdf/driver :asdf/upgrade
-   :asdf/component :asdf/system :asdf/find-component :asdf/operation :asdf/action)
+   :asdf/cache :asdf/component :asdf/system :asdf/find-component :asdf/operation :asdf/action)
   (:export
    #:try-recompiling
    #:cl-source-file #:cl-source-file.cl #:cl-source-file.lsp
    #:basic-load-op #:basic-compile-op #:compile-op-flags #:compile-op-proclamations
    #:load-op #:prepare-op #:compile-op #:test-op #:load-source-op #:prepare-source-op
    #:call-with-around-compile-hook
-   #:perform-lisp-compilation #:perform-lisp-load-fasl #:perform-lisp-load-source))
+   #:perform-lisp-compilation #:perform-lisp-load-fasl #:perform-lisp-load-source #:flags))
 (in-package :asdf/lisp-action)
 
 
 ;;;; Component classes
-(defclass cl-source-file (source-file)
-  ((type :initform "lisp")))
-(defclass cl-source-file.cl (cl-source-file)
-  ((type :initform "cl")))
-(defclass cl-source-file.lsp (cl-source-file)
-  ((type :initform "lsp")))
+(with-upgradability ()
+  (defclass cl-source-file (source-file)
+    ((type :initform "lisp")))
+  (defclass cl-source-file.cl (cl-source-file)
+    ((type :initform "cl")))
+  (defclass cl-source-file.lsp (cl-source-file)
+    ((type :initform "lsp"))))
 
 
 ;;;; Operation classes
-(defclass basic-load-op (operation) ())
-(defclass basic-compile-op (operation)
-  ((proclamations :initarg :proclamations :accessor compile-op-proclamations :initform nil)
-   (flags :initarg :flags :accessor compile-op-flags
-          :initform nil)))
+(with-upgradability ()
+  (defclass basic-load-op (operation) ())
+  (defclass basic-compile-op (operation)
+    ((proclamations :initarg :proclamations :accessor compile-op-proclamations :initform nil)
+     (flags :initarg :flags :accessor compile-op-flags
+            :initform nil))))
 
 ;;; Our default operations: loading into the current lisp image
-(defclass load-op (basic-load-op downward-operation sibling-operation) ())
-(defclass prepare-op (upward-operation sibling-operation)
-  ((sibling-operation :initform 'load-op :allocation :class)))
-(defclass compile-op (basic-compile-op downward-operation)
-  ((downward-operation :initform 'load-op :allocation :class)))
-
-(defclass load-source-op (basic-load-op downward-operation) ())
-(defclass prepare-source-op (upward-operation sibling-operation)
-  ((sibling-operation :initform 'load-source-op :allocation :class)))
+(with-upgradability ()
+  (defclass load-op (basic-load-op downward-operation sibling-operation) ())
+  (defclass prepare-op (upward-operation sibling-operation)
+    ((sibling-operation :initform 'load-op :allocation :class)))
+  (defclass compile-op (basic-compile-op downward-operation)
+    ((downward-operation :initform 'load-op :allocation :class)))
+
+  (defclass load-source-op (basic-load-op downward-operation) ())
+  (defclass prepare-source-op (upward-operation sibling-operation)
+    ((sibling-operation :initform 'load-source-op :allocation :class)))
 
-(defclass test-op (operation) ())
+  (defclass test-op (operation) ()))
 
 
 ;;;; prepare-op, compile-op and load-op
 
 ;;; prepare-op
-(defmethod action-description ((o prepare-op) (c component))
-  (declare (ignorable o))
-  (format nil (compatfmt "~@<loading dependencies of ~3i~_~A~@:>") c))
-(defmethod perform ((o prepare-op) (c component))
-  (declare (ignorable o c))
-  nil)
-(defmethod input-files ((o prepare-op) (c component))
-  (declare (ignorable o c))
-  nil)
-(defmethod input-files ((o prepare-op) (s system))
-  (declare (ignorable o))
-  (if-let (it (system-source-file s)) (list it)))
+(with-upgradability ()
+  (defmethod action-description ((o prepare-op) (c component))
+    (declare (ignorable o))
+    (format nil (compatfmt "~@<loading dependencies of ~3i~_~A~@:>") c))
+  (defmethod perform ((o prepare-op) (c component))
+    (declare (ignorable o c))
+    nil)
+  (defmethod input-files ((o prepare-op) (c component))
+    (declare (ignorable o c))
+    nil)
+  (defmethod input-files ((o prepare-op) (s system))
+    (declare (ignorable o))
+    (if-let (it (system-source-file s)) (list it))))
 
 ;;; compile-op
-(defmethod action-description ((o compile-op) (c component))
-  (declare (ignorable o))
-  (format nil (compatfmt "~@<compiling ~3i~_~A~@:>") c))
-(defmethod action-description ((o compile-op) (c parent-component))
-  (declare (ignorable o))
-  (format nil (compatfmt "~@<completing compilation for ~3i~_~A~@:>") c))
-(defgeneric* call-with-around-compile-hook (component thunk))
-(defmethod call-with-around-compile-hook ((c component) function)
-  (call-around-hook (around-compile-hook c) function))
-(defun* perform-lisp-compilation (o c)
-  (let (;; Before 2.26.53, that was unfortunately component-pathname. Now,
-        ;; we consult input-files, the first of which should be the one to compile-file
-        (input-file (first (input-files o c)))
-        ;; on some implementations, there are more than one output-file,
-        ;; but the first one should always be the primary fasl that gets loaded.
-        (outputs (output-files o c)))
-    (multiple-value-bind (output warnings-p failure-p)
-        (destructuring-bind
-            (output-file
-             &optional
-               #+clisp lib-file
-               #+(or ecl mkcl) object-file
-               #+(or clozure sbcl) warnings-file) outputs
-          (call-with-around-compile-hook
-           c #'(lambda (&rest flags)
-                 (with-muffled-compiler-conditions ()
-                   (apply 'compile-file* input-file
-                          :output-file output-file
-                          :external-format (component-external-format c)
-                      (append
-                       #+clisp (list :lib-file lib-file)
-                       #+(or ecl mkcl) (list :object-file object-file)
-                       #+(or clozure sbcl) (list :warnings-file warnings-file)
-                       flags (compile-op-flags o)))))))
-      (check-lisp-compile-results output warnings-p failure-p
-                                  "~/asdf-action::format-action/" (list (cons o c))))))
-
-(defun* report-file-p (f)
-  (equal (pathname-type f) "build-report"))
-(defun* perform-lisp-warnings-check (o c)
-  (check-deferred-warnings
-   (remove-if-not #'warnings-file-p (input-files o c))
-   "~/asdf-action::format-action/" (list (cons o c)))
-  (let* ((output (output-files o c))
-         (report (find-if #'report-file-p output)))
-    (when report
-      (with-open-file (s report :direction :output :if-exists :supersede)
-        (format s ":success~%")))))
-(defmethod perform ((o compile-op) (c cl-source-file))
-  (perform-lisp-compilation o c))
-(defmethod output-files ((o compile-op) (c cl-source-file))
-  (declare (ignorable o))
-  (let* ((i (first (input-files o c)))
-         (f (compile-file-pathname
-             i #+mkcl :fasl-p #+mkcl t #+ecl :type #+ecl :fasl)))
-    `(,f ;; the fasl is the primary output, in first position
-      #+clisp
-      ,@`(,(make-pathname :type "lib" :defaults f))
-      #+(or clozure sbcl)
-      ,@(let ((s (component-system c)))
-          (unless (builtin-system-p s) ; includes ASDF itself
-            `(,(make-pathname :type (warnings-file-type) :defaults f))))
-      #+ecl
-      ,@(unless (use-ecl-byte-compiler-p)
-          `(,(compile-file-pathname i :type :object)))
-      #+mkcl
-      ,(compile-file-pathname i :fasl-p nil)))) ;; object file
-(defmethod component-depends-on ((o compile-op) (c component))
-  (declare (ignorable o))
-  `((prepare-op ,c) ,@(call-next-method)))
-(defmethod perform ((o compile-op) (c static-file))
-  (declare (ignorable o c))
-  nil)
-(defmethod output-files ((o compile-op) (c static-file))
-  (declare (ignorable o c))
-  nil)
-(defmethod perform ((o compile-op) (c system))
-  (declare (ignorable o c))
-  #+(or clozure sbcl) (perform-lisp-warnings-check o c))
-#+(or clozure sbcl)
-(defmethod input-files ((o compile-op) (c system))
-  (declare (ignorable o c))
-  (when *warnings-file-type*
-    (unless (builtin-system-p c)
+(with-upgradability ()
+  (defmethod action-description ((o compile-op) (c component))
+    (declare (ignorable o))
+    (format nil (compatfmt "~@<compiling ~3i~_~A~@:>") c))
+  (defmethod action-description ((o compile-op) (c parent-component))
+    (declare (ignorable o))
+    (format nil (compatfmt "~@<completing compilation for ~3i~_~A~@:>") c))
+  (defgeneric call-with-around-compile-hook (component thunk))
+  (defmethod call-with-around-compile-hook ((c component) function)
+    (call-around-hook (around-compile-hook c) function))
+  (defun perform-lisp-compilation (o c)
+    (let (;; Before 2.26.53, that was unfortunately component-pathname. Now,
+          ;; we consult input-files, the first of which should be the one to compile-file
+          (input-file (first (input-files o c)))
+          ;; on some implementations, there are more than one output-file,
+          ;; but the first one should always be the primary fasl that gets loaded.
+          (outputs (output-files o c)))
+      (multiple-value-bind (output warnings-p failure-p)
+          (destructuring-bind
+              (output-file
+               &optional
+                 #+clisp lib-file
+                 #+(or ecl mkcl) object-file
+                 warnings-file) outputs
+            (call-with-around-compile-hook
+             c #'(lambda (&rest flags)
+                   (with-muffled-compiler-conditions ()
+                     (apply 'compile-file* input-file
+                            :output-file output-file
+                            :external-format (component-external-format c)
+                            :warnings-file warnings-file
+                            (append
+                             #+clisp (list :lib-file lib-file)
+                             #+(or ecl mkcl) (list :object-file object-file)
+                             flags (compile-op-flags o)))))))
+        (check-lisp-compile-results output warnings-p failure-p
+                                    "~/asdf-action::format-action/" (list (cons o c))))))
+
+  (defun report-file-p (f)
+    (equal (pathname-type f) "build-report"))
+  (defun perform-lisp-warnings-check (o c)
+    (let* ((expected-warnings-files (remove-if-not #'warnings-file-p (input-files o c)))
+           (actual-warnings-files (loop :for w :in expected-warnings-files
+                                        :when (get-file-stamp w)
+                                          :collect w
+                                        :else :do (warn "Missing warnings file ~S while ~A"
+                                                        w (action-description o c)))))
+      (check-deferred-warnings actual-warnings-files)
+      (let* ((output (output-files o c))
+             (report (find-if #'report-file-p output)))
+        (when report
+          (with-open-file (s report :direction :output :if-exists :supersede)
+            (format s ":success~%"))))))
+  (defmethod perform ((o compile-op) (c cl-source-file))
+    (perform-lisp-compilation o c))
+  (defmethod output-files ((o compile-op) (c cl-source-file))
+    (declare (ignorable o))
+    (let* ((i (first (input-files o c)))
+           (f (compile-file-pathname
+               i #+mkcl :fasl-p #+mkcl t #+ecl :type #+ecl :fasl)))
+      `(,f ;; the fasl is the primary output, in first position
+        #+clisp
+        ,@`(,(make-pathname :type "lib" :defaults f))
+        #+ecl
+        ,@(unless (use-ecl-byte-compiler-p)
+            `(,(compile-file-pathname i :type :object)))
+        #+mkcl
+        ,(compile-file-pathname i :fasl-p nil) ;; object file
+        ,@(when (and *warnings-file-type* (not (builtin-system-p (component-system c))))
+            `(,(make-pathname :type *warnings-file-type* :defaults f))))))
+  (defmethod component-depends-on ((o compile-op) (c component))
+    (declare (ignorable o))
+    `((prepare-op ,c) ,@(call-next-method)))
+  (defmethod perform ((o compile-op) (c static-file))
+    (declare (ignorable o c))
+    nil)
+  (defmethod output-files ((o compile-op) (c static-file))
+    (declare (ignorable o c))
+    nil)
+  (defmethod perform ((o compile-op) (c system))
+    (when (and *warnings-file-type* (not (builtin-system-p c)))
+      (perform-lisp-warnings-check o c)))
+  (defmethod input-files ((o compile-op) (c system))
+    (when (and *warnings-file-type* (not (builtin-system-p c)))
       ;; The most correct way to do it would be to use:
       ;; (traverse-sub-actions o c :other-systems nil :keep-operation 'compile-op :keep-component 'cl-source-file)
       ;; but it's expensive and we don't care too much about file order or ASDF extensions.
       (loop :for sub :in (sub-components c :type 'cl-source-file)
-            :nconc (remove-if-not 'warnings-file-p (output-files o sub))))))
-#+sbcl
-(defmethod output-files ((o compile-op) (c system))
-  (unless (builtin-system-p c)
-    (if-let ((pathname (component-pathname c)))
-      (list (subpathname pathname (component-name c) :type "build-report")))))
+            :nconc (remove-if-not 'warnings-file-p (output-files o sub)))))
+  (defmethod output-files ((o compile-op) (c system))
+    (when (and *warnings-file-type* (not (builtin-system-p c)))
+      (if-let ((pathname (component-pathname c)))
+        (list (subpathname pathname (component-name c) :type "build-report"))))))
 
 ;;; load-op
-(defmethod action-description ((o load-op) (c cl-source-file))
-  (declare (ignorable o))
-  (format nil (compatfmt "~@<loading FASL for ~3i~_~A~@:>") c))
-(defmethod action-description ((o load-op) (c parent-component))
-  (declare (ignorable o))
-  (format nil (compatfmt "~@<completing load for ~3i~_~A~@:>") c))
-(defmethod action-description ((o load-op) component)
-  (declare (ignorable o))
-  (format nil (compatfmt "~@<loading ~3i~_~A~@:>")
-          component))
-(defmethod perform-with-restarts ((o load-op) (c cl-source-file))
-  (loop
-    (restart-case
-        (return (call-next-method))
-      (try-recompiling ()
-        :report (lambda (s)
-                  (format s "Recompile ~a and try loading it again"
-                          (component-name c)))
-        (perform (find-operation o 'compile-op) c)))))
-(defun* perform-lisp-load-fasl (o c)
-  (if-let (fasl (first (input-files o c)))
-    (with-muffled-loader-conditions () (load* fasl))))
-(defmethod perform ((o load-op) (c cl-source-file))
-  (perform-lisp-load-fasl o c))
-(defmethod perform ((o load-op) (c static-file))
-  (declare (ignorable o c))
-  nil)
-(defmethod component-depends-on ((o load-op) (c component))
-  (declare (ignorable o))
-  ;; NB: even though compile-op depends-on on prepare-op,
-  ;; it is not needed-in-image-p, whereas prepare-op is,
-  ;; so better not omit prepare-op and think it will happen.
-  `((prepare-op ,c) (compile-op ,c) ,@(call-next-method)))
+(with-upgradability ()
+  (defmethod action-description ((o load-op) (c cl-source-file))
+    (declare (ignorable o))
+    (format nil (compatfmt "~@<loading FASL for ~3i~_~A~@:>") c))
+  (defmethod action-description ((o load-op) (c parent-component))
+    (declare (ignorable o))
+    (format nil (compatfmt "~@<completing load for ~3i~_~A~@:>") c))
+  (defmethod action-description ((o load-op) component)
+    (declare (ignorable o))
+    (format nil (compatfmt "~@<loading ~3i~_~A~@:>")
+            component))
+  (defmethod perform-with-restarts ((o load-op) (c cl-source-file))
+    (loop
+      (restart-case
+          (return (call-next-method))
+        (try-recompiling ()
+          :report (lambda (s)
+                    (format s "Recompile ~a and try loading it again"
+                            (component-name c)))
+          (perform (find-operation o 'compile-op) c)))))
+  (defun perform-lisp-load-fasl (o c)
+    (if-let (fasl (first (input-files o c)))
+      (with-muffled-loader-conditions () (load* fasl))))
+  (defmethod perform ((o load-op) (c cl-source-file))
+    (perform-lisp-load-fasl o c))
+  (defmethod perform ((o load-op) (c static-file))
+    (declare (ignorable o c))
+    nil)
+  (defmethod component-depends-on ((o load-op) (c component))
+    (declare (ignorable o))
+    ;; NB: even though compile-op depends-on on prepare-op,
+    ;; it is not needed-in-image-p, whereas prepare-op is,
+    ;; so better not omit prepare-op and think it will happen.
+    `((prepare-op ,c) (compile-op ,c) ,@(call-next-method))))
 
 
 ;;;; prepare-source-op, load-source-op
 
 ;;; prepare-source-op
-(defmethod action-description ((o prepare-source-op) (c component))
-  (declare (ignorable o))
-  (format nil (compatfmt "~@<loading source for dependencies of ~3i~_~A~@:>") c))
-(defmethod input-files ((o prepare-source-op) (c component))
-  (declare (ignorable o c))
-  nil)
-(defmethod input-files ((o prepare-source-op) (s system))
-  (declare (ignorable o))
-  (if-let (it (system-source-file s)) (list it)))
-(defmethod perform ((o prepare-source-op) (c component))
-  (declare (ignorable o c))
-  nil)
+(with-upgradability ()
+  (defmethod action-description ((o prepare-source-op) (c component))
+    (declare (ignorable o))
+    (format nil (compatfmt "~@<loading source for dependencies of ~3i~_~A~@:>") c))
+  (defmethod input-files ((o prepare-source-op) (c component))
+    (declare (ignorable o c))
+    nil)
+  (defmethod input-files ((o prepare-source-op) (s system))
+    (declare (ignorable o))
+    (if-let (it (system-source-file s)) (list it)))
+  (defmethod perform ((o prepare-source-op) (c component))
+    (declare (ignorable o c))
+    nil))
 
 ;;; load-source-op
-(defmethod action-description ((o load-source-op) c)
-  (declare (ignorable o))
-  (format nil (compatfmt "~@<Loading source of ~3i~_~A~@:>") c))
-(defmethod action-description ((o load-source-op) (c parent-component))
-  (declare (ignorable o))
-  (format nil (compatfmt "~@<Loaded source of ~3i~_~A~@:>") c))
-(defmethod component-depends-on ((o load-source-op) (c component))
-  (declare (ignorable o))
-  `((prepare-source-op ,c) ,@(call-next-method)))
-(defun* perform-lisp-load-source (o c)
-  (call-with-around-compile-hook
-   c #'(lambda ()
-         (with-muffled-loader-conditions ()
-           (load* (first (input-files o c))
-                  :external-format (component-external-format c))))))
-
-(defmethod perform ((o load-source-op) (c cl-source-file))
-  (perform-lisp-load-source o c))
-(defmethod perform ((o load-source-op) (c static-file))
-  (declare (ignorable o c))
-  nil)
-(defmethod output-files ((o load-source-op) (c component))
-  (declare (ignorable o c))
-  nil)
+(with-upgradability ()
+  (defmethod action-description ((o load-source-op) c)
+    (declare (ignorable o))
+    (format nil (compatfmt "~@<Loading source of ~3i~_~A~@:>") c))
+  (defmethod action-description ((o load-source-op) (c parent-component))
+    (declare (ignorable o))
+    (format nil (compatfmt "~@<Loaded source of ~3i~_~A~@:>") c))
+  (defmethod component-depends-on ((o load-source-op) (c component))
+    (declare (ignorable o))
+    `((prepare-source-op ,c) ,@(call-next-method)))
+  (defun perform-lisp-load-source (o c)
+    (call-with-around-compile-hook
+     c #'(lambda ()
+           (with-muffled-loader-conditions ()
+             (load* (first (input-files o c))
+                    :external-format (component-external-format c))))))
+
+  (defmethod perform ((o load-source-op) (c cl-source-file))
+    (perform-lisp-load-source o c))
+  (defmethod perform ((o load-source-op) (c static-file))
+    (declare (ignorable o c))
+    nil)
+  (defmethod output-files ((o load-source-op) (c component))
+    (declare (ignorable o c))
+    nil))
 
 
 ;;;; test-op
-(defmethod perform ((o test-op) (c component))
-  (declare (ignorable o c))
-  nil)
-(defmethod operation-done-p ((o test-op) (c system))
-  "Testing a system is _never_ done."
-  (declare (ignorable o c))
-  nil)
-(defmethod component-depends-on ((o test-op) (c system))
-  (declare (ignorable o))
-  `((load-op ,c) ,@(call-next-method)))
+(with-upgradability ()
+  (defmethod perform ((o test-op) (c component))
+    (declare (ignorable o c))
+    nil)
+  (defmethod operation-done-p ((o test-op) (c system))
+    "Testing a system is _never_ done."
+    (declare (ignorable o c))
+    nil)
+  (defmethod component-depends-on ((o test-op) (c system))
+    (declare (ignorable o))
+    `((load-op ,c) ,@(call-next-method))))
 
 ;;;; -------------------------------------------------------------------------
 ;;;; Plan
@@ -6469,7 +6775,7 @@
   (:use :asdf/common-lisp :asdf/driver :asdf/upgrade
    :asdf/component :asdf/operation :asdf/system
    :asdf/cache :asdf/find-system :asdf/find-component
-   :asdf/operation :asdf/action)
+   :asdf/operation :asdf/action :asdf/lisp-action)
   (:export
    #:component-operation-time #:mark-operation-done
    #:plan-traversal #:sequential-plan #:*default-plan-class*
@@ -6494,411 +6800,413 @@
 (in-package :asdf/plan)
 
 ;;;; Generic plan traversal class
-
-(defclass plan-traversal ()
-  ((system :initform nil :initarg :system :accessor plan-system)
-   (forced :initform nil :initarg :force :accessor plan-forced)
-   (forced-not :initform nil :initarg :force-not :accessor plan-forced-not)
-   (total-action-count :initform 0 :accessor plan-total-action-count)
-   (planned-action-count :initform 0 :accessor plan-planned-action-count)
-   (planned-output-action-count :initform 0 :accessor plan-planned-output-action-count)
-   (visited-actions :initform (make-hash-table :test 'equal) :accessor plan-visited-actions)
-   (visiting-action-set :initform (make-hash-table :test 'equal) :accessor plan-visiting-action-set)
-   (visiting-action-list :initform () :accessor plan-visiting-action-list)))
+(with-upgradability ()
+  (defclass plan-traversal ()
+    ((system :initform nil :initarg :system :accessor plan-system)
+     (forced :initform nil :initarg :force :accessor plan-forced)
+     (forced-not :initform nil :initarg :force-not :accessor plan-forced-not)
+     (total-action-count :initform 0 :accessor plan-total-action-count)
+     (planned-action-count :initform 0 :accessor plan-planned-action-count)
+     (planned-output-action-count :initform 0 :accessor plan-planned-output-action-count)
+     (visited-actions :initform (make-hash-table :test 'equal) :accessor plan-visited-actions)
+     (visiting-action-set :initform (make-hash-table :test 'equal) :accessor plan-visiting-action-set)
+     (visiting-action-list :initform () :accessor plan-visiting-action-list))))
 
 
 ;;;; Planned action status
-
-(defgeneric* plan-action-status (plan operation component)
-  (:documentation "Returns the ACTION-STATUS associated to
+(with-upgradability ()
+  (defgeneric plan-action-status (plan operation component)
+    (:documentation "Returns the ACTION-STATUS associated to
 the action of OPERATION on COMPONENT in the PLAN"))
 
-(defgeneric* (setf plan-action-status) (new-status plan operation component)
-  (:documentation "Sets the ACTION-STATUS associated to
+  (defgeneric (setf plan-action-status) (new-status plan operation component)
+    (:documentation "Sets the ACTION-STATUS associated to
 the action of OPERATION on COMPONENT in the PLAN"))
 
-(defclass planned-action-status (action-status)
-  ((planned-p
-    :initarg :planned-p :reader action-planned-p
-    :documentation "a boolean, true iff the action was included in the plan.")
-   (index
-    :initarg :index :reader action-index
-    :documentation "an integer, counting all traversed actions in traversal order."))
-  (:documentation "Status of an action in a plan"))
-
-(defmethod print-object ((status planned-action-status) stream)
-  (print-unreadable-object (status stream :type t)
-    (with-slots (stamp done-p planned-p) status
-      (format stream "~@{~S~^ ~}" :stamp stamp :done-p done-p :planned-p planned-p))))
-
-(defmethod action-planned-p (action-status)
-  (declare (ignorable action-status)) ; default method for non planned-action-status objects
-  t)
-
-;; TODO: eliminate NODE-FOR, use CONS.
-;; Supposes cleaner protocol for operation initargs passed to MAKE-OPERATION.
-;; However, see also component-operation-time and mark-operation-done
-(defun* node-for (o c) (cons (type-of o) c))
-
-(defun* action-already-done-p (plan operation component)
-  (action-done-p (plan-action-status plan operation component)))
-
-(defmethod plan-action-status ((plan null) (o operation) (c component))
-  (declare (ignorable plan))
-  (multiple-value-bind (stamp done-p) (component-operation-time o c)
-    (make-instance 'action-status :stamp stamp :done-p done-p)))
-
-(defmethod (setf plan-action-status) (new-status (plan null) (o operation) (c component))
-  (declare (ignorable plan))
-  (let ((to (type-of o))
-        (times (component-operation-times c)))
-    (if (action-done-p new-status)
-        (remhash to times)
-        (setf (gethash to times) (action-stamp new-status))))
-  new-status)
+  (defclass planned-action-status (action-status)
+    ((planned-p
+      :initarg :planned-p :reader action-planned-p
+      :documentation "a boolean, true iff the action was included in the plan.")
+     (index
+      :initarg :index :reader action-index
+      :documentation "an integer, counting all traversed actions in traversal order."))
+    (:documentation "Status of an action in a plan"))
+
+  (defmethod print-object ((status planned-action-status) stream)
+    (print-unreadable-object (status stream :type t :identity nil)
+      (with-slots (stamp done-p planned-p index) status
+        (format stream "~@{~S~^ ~}" :stamp stamp :done-p done-p :planned-p planned-p :index index))))
+
+  (defmethod action-planned-p (action-status)
+    (declare (ignorable action-status)) ; default method for non planned-action-status objects
+    t)
+
+  ;; TODO: eliminate NODE-FOR, use CONS.
+  ;; Supposes cleaner protocol for operation initargs passed to MAKE-OPERATION.
+  ;; However, see also component-operation-time and mark-operation-done
+  (defun node-for (o c) (cons (type-of o) c))
+
+  (defun action-already-done-p (plan operation component)
+    (action-done-p (plan-action-status plan operation component)))
+
+  (defmethod plan-action-status ((plan null) (o operation) (c component))
+    (declare (ignorable plan))
+    (multiple-value-bind (stamp done-p) (component-operation-time o c)
+      (make-instance 'action-status :stamp stamp :done-p done-p)))
+
+  (defmethod (setf plan-action-status) (new-status (plan null) (o operation) (c component))
+    (declare (ignorable plan))
+    (let ((to (type-of o))
+          (times (component-operation-times c)))
+      (if (action-done-p new-status)
+          (remhash to times)
+          (setf (gethash to times) (action-stamp new-status))))
+    new-status))
 
 
 ;;;; forcing
-
-(defgeneric* action-forced-p (plan operation component))
-(defgeneric* action-forced-not-p (plan operation component))
-
-(defun* normalize-forced-systems (x system)
-  (etypecase x
-    ((member nil :all) x)
-    (cons (list-to-hash-set (mapcar #'coerce-name x)))
-    ((eql t) (when system (list-to-hash-set (list (coerce-name system)))))))
-
-(defun* action-override-p (plan operation component override-accessor)
-  (declare (ignorable operation))
-  (let* ((override (funcall override-accessor plan)))
-    (and override
-         (if (typep override 'hash-table)
-             (gethash (coerce-name (component-system (find-component () component))) override)
-             t))))
-
-(defmethod action-forced-p (plan operation component)
-  (and
-   ;; Did the user ask us to re-perform the action?
-   (action-override-p plan operation component 'plan-forced)
-   ;; You really can't force a builtin system and :all doesn't apply to it,
-   ;; except it it's the specifically the system currently being built.
-   (not (let ((system (component-system component)))
-          (and (builtin-system-p system)
-               (not (eq system (plan-system plan))))))))
-
-(defmethod action-forced-not-p (plan operation component)
-  (and
-   ;; Did the user ask us to not re-perform the action?
-   (action-override-p plan operation component 'plan-forced-not)
-   ;; Force takes precedence over force-not
-   (not (action-forced-p plan operation component))))
-
-(defmethod action-forced-p ((plan null) operation component)
-  (declare (ignorable plan operation component))
-  nil)
-
-(defmethod action-forced-not-p ((plan null) operation component)
-  (declare (ignorable plan operation component))
-  nil)
+(with-upgradability ()
+  (defgeneric action-forced-p (plan operation component))
+  (defgeneric action-forced-not-p (plan operation component))
+
+  (defun normalize-forced-systems (x system)
+    (etypecase x
+      ((member nil :all) x)
+      (cons (list-to-hash-set (mapcar #'coerce-name x)))
+      ((eql t) (when system (list-to-hash-set (list (coerce-name system)))))))
+
+  (defun action-override-p (plan operation component override-accessor)
+    (declare (ignorable operation))
+    (let* ((override (funcall override-accessor plan)))
+      (and override
+           (if (typep override 'hash-table)
+               (gethash (coerce-name (component-system (find-component () component))) override)
+               t))))
+
+  (defmethod action-forced-p (plan operation component)
+    (and
+     ;; Did the user ask us to re-perform the action?
+     (action-override-p plan operation component 'plan-forced)
+     ;; You really can't force a builtin system and :all doesn't apply to it,
+     ;; except it it's the specifically the system currently being built.
+     (not (let ((system (component-system component)))
+            (and (builtin-system-p system)
+                 (not (eq system (plan-system plan))))))))
+
+  (defmethod action-forced-not-p (plan operation component)
+    (and
+     ;; Did the user ask us to not re-perform the action?
+     (action-override-p plan operation component 'plan-forced-not)
+     ;; Force takes precedence over force-not
+     (not (action-forced-p plan operation component))))
+
+  (defmethod action-forced-p ((plan null) operation component)
+    (declare (ignorable plan operation component))
+    nil)
+
+  (defmethod action-forced-not-p ((plan null) operation component)
+    (declare (ignorable plan operation component))
+    nil))
 
 
 ;;;; action-valid-p
-
-(defgeneric action-valid-p (plan operation component)
-  (:documentation "Is this action valid to include amongst dependencies?"))
-(defmethod action-valid-p (plan operation (c component))
-  (declare (ignorable plan operation))
-  (if-let (it (component-if-feature c)) (featurep it) t))
-(defmethod action-valid-p (plan (o null) c) (declare (ignorable plan o c)) nil)
-(defmethod action-valid-p (plan o (c null)) (declare (ignorable plan o c)) nil)
-(defmethod action-valid-p ((plan null) operation component)
-  (declare (ignorable plan operation component))
-  (and operation component t))
+(with-upgradability ()
+  (defgeneric action-valid-p (plan operation component)
+    (:documentation "Is this action valid to include amongst dependencies?"))
+  (defmethod action-valid-p (plan operation (c component))
+    (declare (ignorable plan operation))
+    (if-let (it (component-if-feature c)) (featurep it) t))
+  (defmethod action-valid-p (plan (o null) c) (declare (ignorable plan o c)) nil)
+  (defmethod action-valid-p (plan o (c null)) (declare (ignorable plan o c)) nil)
+  (defmethod action-valid-p ((plan null) operation component)
+    (declare (ignorable plan operation component))
+    (and operation component t)))
 
 
 ;;;; Is the action needed in this image?
-
-(defgeneric* needed-in-image-p (operation component)
-  (:documentation "Is the action of OPERATION on COMPONENT needed in the current image to be meaningful,
+(with-upgradability ()
+  (defgeneric needed-in-image-p (operation component)
+    (:documentation "Is the action of OPERATION on COMPONENT needed in the current image to be meaningful,
     or could it just as well have been done in another Lisp image?"))
 
-(defmethod needed-in-image-p ((o operation) (c component))
-  ;; We presume that actions that modify the filesystem don't need be run
-  ;; in the current image if they have already been done in another,
-  ;; and can be run in another process (e.g. a fork),
-  ;; whereas those that don't are meant to side-effect the current image and can't.
-  (not (output-files o c)))
+  (defmethod needed-in-image-p ((o operation) (c component))
+    ;; We presume that actions that modify the filesystem don't need be run
+    ;; in the current image if they have already been done in another,
+    ;; and can be run in another process (e.g. a fork),
+    ;; whereas those that don't are meant to side-effect the current image and can't.
+    (not (output-files o c))))
 
 
 ;;;; Visiting dependencies of an action and computing action stamps
+(with-upgradability ()
+  (defun map-direct-dependencies (operation component fun)
+    (loop* :for (dep-o-spec . dep-c-specs) :in (component-depends-on operation component)
+           :unless (eq dep-o-spec 'feature) ;; avoid the "FEATURE" misfeature
+           :do (loop :with dep-o = (find-operation operation dep-o-spec)
+                     :for dep-c-spec :in dep-c-specs
+                     :for dep-c = (resolve-dependency-spec component dep-c-spec)
+                     :do (funcall fun dep-o dep-c))))
 
-(defun* map-direct-dependencies (operation component fun)
-  (loop* :for (dep-o-spec . dep-c-specs) :in (component-depends-on operation component)
-     :unless (eq dep-o-spec 'feature) ;; avoid the "FEATURE" misfeature
-        :do (loop :with dep-o = (find-operation operation dep-o-spec)
-                  :for dep-c-spec :in dep-c-specs
-                  :for dep-c = (resolve-dependency-spec component dep-c-spec)
-                  :do (funcall fun dep-o dep-c))))
-
-(defun* reduce-direct-dependencies (operation component combinator seed)
-  (map-direct-dependencies
-   operation component
-   #'(lambda (dep-o dep-c)
-       (setf seed (funcall combinator dep-o dep-c seed))))
-  seed)
-
-(defun* direct-dependencies (operation component)
-  (reduce-direct-dependencies operation component #'acons nil))
-
-(defun* visit-dependencies (plan operation component dependency-stamper &aux stamp)
-  (map-direct-dependencies
-   operation component
-   #'(lambda (dep-o dep-c)
-       (when (action-valid-p plan dep-o dep-c)
-         (latest-stamp-f stamp (funcall dependency-stamper dep-o dep-c)))))
-  stamp)
-
-(defmethod compute-action-stamp (plan (o operation) (c component) &key just-done)
-  ;; In a distant future, get-file-stamp and component-operation-time
-  ;; shall also be parametrized by the plan, or by a second model object.
-  (let* ((stamp-lookup #'(lambda (o c)
-                           (if-let (it (plan-action-status plan o c)) (action-stamp it) t)))
-         (out-files (output-files o c))
-         (in-files (input-files o c))
-         ;; Three kinds of actions:
-         (out-op (and out-files t)) ; those that create files on the filesystem
-         ;(image-op (and in-files (null out-files))) ; those that load stuff into the image
-         ;(null-op (and (null out-files) (null in-files))) ; dependency placeholders that do nothing
-         ;; When was the thing last actually done? (Now, or ask.)
-         (op-time (or just-done (component-operation-time o c)))
-         ;; Accumulated timestamp from dependencies (or T if forced or out-of-date)
-         (dep-stamp (visit-dependencies plan o c stamp-lookup))
-         ;; Time stamps from the files at hand, and whether any is missing
-         (out-stamps (mapcar (if just-done 'register-file-stamp 'get-file-stamp) out-files))
-         (in-stamps (mapcar #'get-file-stamp in-files))
-         (missing-in
-           (loop :for f :in in-files :for s :in in-stamps :unless s :collect f))
-         (missing-out
-           (loop :for f :in out-files :for s :in out-stamps :unless s :collect f))
-         (all-present (not (or missing-in missing-out)))
-         ;; Has any input changed since we last generated the files?
-         (earliest-out (stamps-earliest out-stamps))
-         (latest-in (stamps-latest (cons dep-stamp in-stamps)))
-         (up-to-date-p (stamp<= latest-in earliest-out))
-         ;; If everything is up to date, the latest of inputs and outputs is our stamp
-         (done-stamp (stamps-latest (cons latest-in out-stamps))))
-    ;; Warn if some files are missing:
-    ;; either our model is wrong or some other process is messing with our files.
-    (when (and just-done (not all-present))
-      (warn "~A completed without ~:[~*~;~*its input file~:p~2:*~{ ~S~}~*~]~
+  (defun reduce-direct-dependencies (operation component combinator seed)
+    (map-direct-dependencies
+     operation component
+     #'(lambda (dep-o dep-c)
+         (setf seed (funcall combinator dep-o dep-c seed))))
+    seed)
+
+  (defun direct-dependencies (operation component)
+    (reduce-direct-dependencies operation component #'acons nil))
+
+  (defun visit-dependencies (plan operation component dependency-stamper &aux stamp)
+    (map-direct-dependencies
+     operation component
+     #'(lambda (dep-o dep-c)
+         (when (action-valid-p plan dep-o dep-c)
+           (latest-stamp-f stamp (funcall dependency-stamper dep-o dep-c)))))
+    stamp)
+
+  (defmethod compute-action-stamp (plan (o operation) (c component) &key just-done)
+    ;; In a distant future, get-file-stamp and component-operation-time
+    ;; shall also be parametrized by the plan, or by a second model object.
+    (let* ((stamp-lookup #'(lambda (o c)
+                             (if-let (it (plan-action-status plan o c)) (action-stamp it) t)))
+           (out-files (output-files o c))
+           (in-files (input-files o c))
+           ;; Three kinds of actions:
+           (out-op (and out-files t)) ; those that create files on the filesystem
+                                        ;(image-op (and in-files (null out-files))) ; those that load stuff into the image
+                                        ;(null-op (and (null out-files) (null in-files))) ; dependency placeholders that do nothing
+           ;; When was the thing last actually done? (Now, or ask.)
+           (op-time (or just-done (component-operation-time o c)))
+           ;; Accumulated timestamp from dependencies (or T if forced or out-of-date)
+           (dep-stamp (visit-dependencies plan o c stamp-lookup))
+           ;; Time stamps from the files at hand, and whether any is missing
+           (out-stamps (mapcar (if just-done 'register-file-stamp 'get-file-stamp) out-files))
+           (in-stamps (mapcar #'get-file-stamp in-files))
+           (missing-in
+             (loop :for f :in in-files :for s :in in-stamps :unless s :collect f))
+           (missing-out
+             (loop :for f :in out-files :for s :in out-stamps :unless s :collect f))
+           (all-present (not (or missing-in missing-out)))
+           ;; Has any input changed since we last generated the files?
+           (earliest-out (stamps-earliest out-stamps))
+           (latest-in (stamps-latest (cons dep-stamp in-stamps)))
+           (up-to-date-p (stamp<= latest-in earliest-out))
+           ;; If everything is up to date, the latest of inputs and outputs is our stamp
+           (done-stamp (stamps-latest (cons latest-in out-stamps))))
+      ;; Warn if some files are missing:
+      ;; either our model is wrong or some other process is messing with our files.
+      (when (and just-done (not all-present))
+        (warn "~A completed without ~:[~*~;~*its input file~:p~2:*~{ ~S~}~*~]~
              ~:[~; or ~]~:[~*~;~*its output file~:p~2:*~{ ~S~}~*~]"
-            (action-description o c)
-            missing-in (length missing-in) (and missing-in missing-out)
-            missing-out (length missing-out)))
-    ;; Note that we use stamp<= instead of stamp< to play nice with generated files.
-    ;; Any race condition is intrinsic to the limited timestamp resolution.
-    (if (or just-done ;; The done-stamp is valid: if we're just done, or
-            ;; if all filesystem effects are up-to-date and there's no invalidating reason.
-            (and all-present up-to-date-p (operation-done-p o c) (not (action-forced-p plan o c))))
-        (values done-stamp ;; return the hard-earned timestamp
-                (or just-done
-                    (or out-op ;; a file-creating op is done when all files are up to date
-                        ;; a image-effecting a placeholder op is done when it was actually run,
-                        (and op-time (eql op-time done-stamp))))) ;; with the matching stamp
-        ;; done-stamp invalid: return a timestamp in an indefinite future, action not done yet
-        (values t nil))))
+              (action-description o c)
+              missing-in (length missing-in) (and missing-in missing-out)
+              missing-out (length missing-out)))
+      ;; Note that we use stamp<= instead of stamp< to play nice with generated files.
+      ;; Any race condition is intrinsic to the limited timestamp resolution.
+      (if (or just-done ;; The done-stamp is valid: if we're just done, or
+              ;; if all filesystem effects are up-to-date and there's no invalidating reason.
+              (and all-present up-to-date-p (operation-done-p o c) (not (action-forced-p plan o c))))
+          (values done-stamp ;; return the hard-earned timestamp
+                  (or just-done
+                      (or out-op ;; a file-creating op is done when all files are up to date
+                          ;; a image-effecting a placeholder op is done when it was actually run,
+                          (and op-time (eql op-time done-stamp))))) ;; with the matching stamp
+          ;; done-stamp invalid: return a timestamp in an indefinite future, action not done yet
+          (values t nil)))))
 
-;;;; Generic support for plan-traversal
 
-(defgeneric* plan-record-dependency (plan operation component))
+;;;; Generic support for plan-traversal
+(with-upgradability ()
+  (defgeneric plan-record-dependency (plan operation component))
 
-(defgeneric call-while-visiting-action (plan operation component function)
-  (:documentation "Detect circular dependencies"))
+  (defgeneric call-while-visiting-action (plan operation component function)
+    (:documentation "Detect circular dependencies"))
 
-(defmethod initialize-instance :after ((plan plan-traversal)
-                                       &key (force () fp) (force-not () fnp) system
-                                       &allow-other-keys)
-  (with-slots (forced forced-not) plan
-    (when fp (setf forced (normalize-forced-systems force system)))
-    (when fnp (setf forced-not (normalize-forced-systems force-not system)))))
-
-(defmethod (setf plan-action-status) (new-status (plan plan-traversal) (o operation) (c component))
-  (setf (gethash (node-for o c) (plan-visited-actions plan)) new-status))
-
-(defmethod plan-action-status ((plan plan-traversal) (o operation) (c component))
-  (or (and (action-forced-not-p plan o c) (plan-action-status nil o c))
-      (values (gethash (node-for o c) (plan-visited-actions plan)))))
-
-(defmethod action-valid-p ((plan plan-traversal) (o operation) (s system))
-  (and (not (action-forced-not-p plan o s)) (call-next-method)))
-
-(defmethod call-while-visiting-action ((plan plan-traversal) operation component fun)
-  (with-accessors ((action-set plan-visiting-action-set)
-                   (action-list plan-visiting-action-list)) plan
-    (let ((action (cons operation component)))
-      (when (gethash action action-set)
-        (error 'circular-dependency :actions
-               (member action (reverse action-list) :test 'equal)))
-      (setf (gethash action action-set) t)
-      (push action action-list)
-      (unwind-protect
-           (funcall fun)
-        (pop action-list)
-        (setf (gethash action action-set) nil)))))
+  (defmethod initialize-instance :after ((plan plan-traversal)
+                                         &key (force () fp) (force-not () fnp) system
+                                         &allow-other-keys)
+    (with-slots (forced forced-not) plan
+      (when fp (setf forced (normalize-forced-systems force system)))
+      (when fnp (setf forced-not (normalize-forced-systems force-not system)))))
+
+  (defmethod (setf plan-action-status) (new-status (plan plan-traversal) (o operation) (c component))
+    (setf (gethash (node-for o c) (plan-visited-actions plan)) new-status))
+
+  (defmethod plan-action-status ((plan plan-traversal) (o operation) (c component))
+    (or (and (action-forced-not-p plan o c) (plan-action-status nil o c))
+        (values (gethash (node-for o c) (plan-visited-actions plan)))))
+
+  (defmethod action-valid-p ((plan plan-traversal) (o operation) (s system))
+    (and (not (action-forced-not-p plan o s)) (call-next-method)))
+
+  (defmethod call-while-visiting-action ((plan plan-traversal) operation component fun)
+    (with-accessors ((action-set plan-visiting-action-set)
+                     (action-list plan-visiting-action-list)) plan
+      (let ((action (cons operation component)))
+        (when (gethash action action-set)
+          (error 'circular-dependency :actions
+                 (member action (reverse action-list) :test 'equal)))
+        (setf (gethash action action-set) t)
+        (push action action-list)
+        (unwind-protect
+             (funcall fun)
+          (pop action-list)
+          (setf (gethash action action-set) nil))))))
 
 
 ;;;; Actual traversal: traverse-action
+(with-upgradability ()
+  (define-condition circular-dependency (system-definition-error)
+    ((actions :initarg :actions :reader circular-dependency-actions))
+    (:report (lambda (c s)
+               (format s (compatfmt "~@<Circular dependency: ~3i~_~S~@:>")
+                       (circular-dependency-actions c)))))
 
-(define-condition circular-dependency (system-definition-error)
-  ((actions :initarg :actions :reader circular-dependency-actions))
-  (:report (lambda (c s)
-             (format s (compatfmt "~@<Circular dependency: ~3i~_~S~@:>")
-                     (circular-dependency-actions c)))))
-
-(defmacro while-visiting-action ((p o c) &body body)
-  `(call-while-visiting-action ,p ,o ,c #'(lambda () , at body)))
-
-(defgeneric* traverse-action (plan operation component needed-in-image-p))
-
-(defmethod traverse-action (plan operation component needed-in-image-p)
-  (block nil
-    (unless (action-valid-p plan operation component) (return nil))
-    (plan-record-dependency plan operation component)
-    (let* ((aniip (needed-in-image-p operation component))
-           (eniip (and aniip needed-in-image-p))
-           (status (plan-action-status plan operation component)))
-      (when (and status (or (action-done-p status) (action-planned-p status) (not eniip)))
-        ;; Already visited with sufficient need-in-image level: just return the stamp.
-        (return (action-stamp status)))
-      (labels ((visit-action (niip)
-                 (visit-dependencies plan operation component
-                                     #'(lambda (o c) (traverse-action plan o c niip)))
-                 (multiple-value-bind (stamp done-p)
-                     (compute-action-stamp plan operation component)
-                   (let ((add-to-plan-p (or (eql stamp t) (and niip (not done-p)))))
-                     (cond
-                       ((and add-to-plan-p (not niip)) ;; if we need to do it,
-                        (visit-action t)) ;; then we need to do it in the image!
-                       (t
-                        (setf (plan-action-status plan operation component)
-                              (make-instance
-                               'planned-action-status
-                               :stamp stamp
-                               :done-p (and done-p (not add-to-plan-p))
-                               :planned-p add-to-plan-p
-                               :index (if status (action-index status) (incf (plan-total-action-count plan)))))
-                        (when add-to-plan-p
-                          (incf (plan-planned-action-count plan))
-                          (unless aniip
-                            (incf (plan-planned-output-action-count plan))))
-                        stamp))))))
-        (while-visiting-action (plan operation component) ; maintain context, handle circularity.
-          (visit-action eniip))))))
+  (defmacro while-visiting-action ((p o c) &body body)
+    `(call-while-visiting-action ,p ,o ,c #'(lambda () , at body)))
 
+  (defgeneric traverse-action (plan operation component needed-in-image-p))
 
-;;;; Sequential plans (the default)
+  (defmethod traverse-action (plan operation component needed-in-image-p)
+    (block nil
+      (unless (action-valid-p plan operation component) (return nil))
+      (plan-record-dependency plan operation component)
+      (let* ((aniip (needed-in-image-p operation component))
+             (eniip (and aniip needed-in-image-p))
+             (status (plan-action-status plan operation component)))
+        (when (and status (or (action-done-p status) (action-planned-p status) (not eniip)))
+          ;; Already visited with sufficient need-in-image level: just return the stamp.
+          (return (action-stamp status)))
+        (labels ((visit-action (niip)
+                   (visit-dependencies plan operation component
+                                       #'(lambda (o c) (traverse-action plan o c niip)))
+                   (multiple-value-bind (stamp done-p)
+                       (compute-action-stamp plan operation component)
+                     (let ((add-to-plan-p (or (eql stamp t) (and niip (not done-p)))))
+                       (cond
+                         ((and add-to-plan-p (not niip)) ;; if we need to do it,
+                          (visit-action t)) ;; then we need to do it in the image!
+                         (t
+                          (setf (plan-action-status plan operation component)
+                                (make-instance
+                                 'planned-action-status
+                                 :stamp stamp
+                                 :done-p (and done-p (not add-to-plan-p))
+                                 :planned-p add-to-plan-p
+                                 :index (if status (action-index status) (incf (plan-total-action-count plan)))))
+                          (when add-to-plan-p
+                            (incf (plan-planned-action-count plan))
+                            (unless aniip
+                              (incf (plan-planned-output-action-count plan))))
+                          stamp))))))
+          (while-visiting-action (plan operation component) ; maintain context, handle circularity.
+            (visit-action eniip)))))))
 
-(defclass sequential-plan (plan-traversal)
-  ((actions-r :initform nil :accessor plan-actions-r)))
 
-(defgeneric* plan-actions (plan))
-(defmethod plan-actions ((plan sequential-plan))
-  (reverse (plan-actions-r plan)))
-
-(defmethod plan-record-dependency ((plan sequential-plan)
-                                   (operation operation) (component component))
-  (declare (ignorable plan operation component))
-  (values))
-
-(defmethod (setf plan-action-status) :after
-    (new-status (p sequential-plan) (o operation) (c component))
-  (when (action-planned-p new-status)
-    (push (cons o c) (plan-actions-r p))))
+;;;; Sequential plans (the default)
+(with-upgradability ()
+  (defclass sequential-plan (plan-traversal)
+    ((actions-r :initform nil :accessor plan-actions-r)))
+
+  (defgeneric plan-actions (plan))
+  (defmethod plan-actions ((plan sequential-plan))
+    (reverse (plan-actions-r plan)))
+
+  (defmethod plan-record-dependency ((plan sequential-plan)
+                                     (operation operation) (component component))
+    (declare (ignorable plan operation component))
+    (values))
+
+  (defmethod (setf plan-action-status) :after
+      (new-status (p sequential-plan) (o operation) (c component))
+    (when (action-planned-p new-status)
+      (push (cons o c) (plan-actions-r p)))))
 
 
 ;;;; high-level interface: traverse, perform-plan, plan-operates-on-p
-
-(defgeneric* (traverse) (operation component &key &allow-other-keys)
-  (:documentation
-"Generate and return a plan for performing OPERATION on COMPONENT.
+(with-upgradability ()
+  (defgeneric* (traverse) (operation component &key &allow-other-keys)
+    (:documentation
+     "Generate and return a plan for performing OPERATION on COMPONENT.
 
 The plan returned is a list of dotted-pairs. Each pair is the CONS
 of ASDF operation object and a COMPONENT object. The pairs will be
 processed in order by OPERATE."))
-(define-convenience-action-methods traverse (operation component &key))
+  (define-convenience-action-methods traverse (operation component &key))
 
-(defgeneric* perform-plan (plan &key))
-(defgeneric* plan-operates-on-p (plan component))
+  (defgeneric perform-plan (plan &key))
+  (defgeneric plan-operates-on-p (plan component))
 
-(defparameter *default-plan-class* 'sequential-plan)
+  (defparameter *default-plan-class* 'sequential-plan)
 
-(defmethod traverse ((o operation) (c component) &rest keys &key plan-class &allow-other-keys)
-  (let ((plan (apply 'make-instance
-                     (or plan-class *default-plan-class*)
-                     :system (component-system c) (remove-plist-key :plan-class keys))))
-    (traverse-action plan o c t)
-    (plan-actions plan)))
-
-(defmethod perform-plan :around (plan &key)
-  (declare (ignorable plan))
-  (let ((*package* *package*)
-        (*readtable* *readtable*))
-    (with-compilation-unit () ;; backward-compatibility.
-      (call-next-method))))   ;; Going forward, see deferred-warning support in lisp-build.
-
-(defmethod perform-plan ((steps list) &key)
-  (loop* :for (op . component) :in steps :do
-         (perform-with-restarts op component)))
-
-(defmethod plan-operates-on-p ((plan list) (component-path list))
-  (find component-path (mapcar 'cdr plan)
-        :test 'equal :key 'component-find-path))
+  (defmethod traverse ((o operation) (c component) &rest keys &key plan-class &allow-other-keys)
+    (let ((plan (apply 'make-instance
+                       (or plan-class *default-plan-class*)
+                       :system (component-system c) (remove-plist-key :plan-class keys))))
+      (traverse-action plan o c t)
+      (plan-actions plan)))
+
+  (defmethod perform-plan :around (plan &key)
+    (declare (ignorable plan))
+    (let ((*package* *package*)
+          (*readtable* *readtable*))
+      (with-compilation-unit () ;; backward-compatibility.
+        (call-next-method))))   ;; Going forward, see deferred-warning support in lisp-build.
+
+  (defmethod perform-plan ((steps list) &key)
+    (loop* :for (op . component) :in steps :do
+           (perform-with-restarts op component)))
+
+  (defmethod plan-operates-on-p ((plan list) (component-path list))
+    (find component-path (mapcar 'cdr plan)
+          :test 'equal :key 'component-find-path)))
 
 
 ;;;; Incidental traversals 
-
-(defclass filtered-sequential-plan (sequential-plan)
-  ((action-filter :initform t :initarg :action-filter :reader plan-action-filter)
-   (component-type :initform t :initarg :component-type :reader plan-component-type)
-   (keep-operation :initform t :initarg :keep-operation :reader plan-keep-operation)
-   (keep-component :initform t :initarg :keep-component :reader plan-keep-component)))
-
-(defmethod initialize-instance :after ((plan filtered-sequential-plan)
-                                       &key (force () fp) (force-not () fnp)
-                                         other-systems)
-  (declare (ignore force force-not))
-  (with-slots (forced forced-not action-filter system) plan
-    (unless fp (setf forced (normalize-forced-systems (if other-systems :all t) system)))
-    (unless fnp (setf forced-not (normalize-forced-systems (if other-systems nil :all) system)))
-    (setf action-filter (ensure-function action-filter))))
-
-(defmethod action-valid-p ((plan filtered-sequential-plan) o c)
-  (and (funcall (plan-action-filter plan) o c)
-       (typep c (plan-component-type plan))
-       (call-next-method)))
-
-(defmethod traverse-actions (actions &rest keys &key plan-class &allow-other-keys)
-  (let ((plan (apply 'make-instance (or plan-class 'filtered-sequential-plan) keys)))
-    (loop* :for (o . c) :in actions :do
-      (traverse-action plan o c t))
-    (plan-actions plan)))
-
-(defmethod traverse-sub-actions (operation component &rest keys &key &allow-other-keys)
-  (apply 'traverse-actions (direct-dependencies operation component)
-         :system (component-system component) keys))
-
-(defmethod plan-actions ((plan filtered-sequential-plan))
-  (with-slots (keep-operation keep-component) plan
-  (loop* :for (o . c) :in (call-next-method)
-         :when (and (typep o keep-operation)
-                    (typep c keep-component))
-           :collect (cons o c))))
-
-(defmethod required-components (system &rest keys &key (goal-operation 'load-op) &allow-other-keys)
-  (remove-duplicates
-   (mapcar 'cdr (apply 'traverse-sub-actions (make-operation goal-operation) system keys))
-   :from-end t))
+(with-upgradability ()
+  (defclass filtered-sequential-plan (sequential-plan)
+    ((action-filter :initform t :initarg :action-filter :reader plan-action-filter)
+     (component-type :initform t :initarg :component-type :reader plan-component-type)
+     (keep-operation :initform t :initarg :keep-operation :reader plan-keep-operation)
+     (keep-component :initform t :initarg :keep-component :reader plan-keep-component)))
+
+  (defmethod initialize-instance :after ((plan filtered-sequential-plan)
+                                         &key (force () fp) (force-not () fnp)
+                                           other-systems)
+    (declare (ignore force force-not))
+    (with-slots (forced forced-not action-filter system) plan
+      (unless fp (setf forced (normalize-forced-systems (if other-systems :all t) system)))
+      (unless fnp (setf forced-not (normalize-forced-systems (if other-systems nil :all) system)))
+      (setf action-filter (ensure-function action-filter))))
+
+  (defmethod action-valid-p ((plan filtered-sequential-plan) o c)
+    (and (funcall (plan-action-filter plan) o c)
+         (typep c (plan-component-type plan))
+         (call-next-method)))
+
+  (defmethod traverse-actions (actions &rest keys &key plan-class &allow-other-keys)
+    (let ((plan (apply 'make-instance (or plan-class 'filtered-sequential-plan) keys)))
+      (loop* :for (o . c) :in actions :do
+             (traverse-action plan o c t))
+      (plan-actions plan)))
+
+  (define-convenience-action-methods traverse-sub-actions (o c &key))
+  (defmethod traverse-sub-actions ((operation operation) (component component) &rest keys &key &allow-other-keys)
+    (apply 'traverse-actions (direct-dependencies operation component)
+           :system (component-system component) keys))
+
+  (defmethod plan-actions ((plan filtered-sequential-plan))
+    (with-slots (keep-operation keep-component) plan
+      (loop* :for (o . c) :in (call-next-method)
+             :when (and (typep o keep-operation)
+                        (typep c keep-component))
+             :collect (cons o c))))
+
+  (defmethod required-components (system &rest keys &key (goal-operation 'load-op) &allow-other-keys)
+    (remove-duplicates
+     (mapcar 'cdr (apply 'traverse-sub-actions goal-operation system keys))
+     :from-end t)))
 
 ;;;; -------------------------------------------------------------------------
 ;;;; Invoking Operations
@@ -6918,31 +7226,31 @@
    #:upgrade-asdf #:cleanup-upgraded-asdf #:*post-upgrade-hook*))
 (in-package :asdf/operate)
 
-(defgeneric* (operate) (operation component &key &allow-other-keys))
-(define-convenience-action-methods
-    operate (operation component &key)
-    :operation-initargs t ;; backward-compatibility with ASDF1. Yuck.
-    :if-no-component (error 'missing-component :requires component))
-
-(defvar *systems-being-operated* nil
-  "A boolean indicating that some systems are being operated on")
-
-(defmethod operate :around (operation component
-                            &key verbose
-                              (on-warnings *compile-file-warnings-behaviour*)
-                              (on-failure *compile-file-failure-behaviour*) &allow-other-keys)
-  (declare (ignorable operation component))
-  ;; Setup proper bindings around any operate call.
-  (with-system-definitions ()
-    (let* ((*asdf-verbose* verbose)
-           (*verbose-out* (if verbose *standard-output* (make-broadcast-stream)))
-           (*compile-file-warnings-behaviour* on-warnings)
-           (*compile-file-failure-behaviour* on-failure))
-      (call-next-method))))
-
-(defmethod operate ((operation operation) (component component)
-                    &rest args &key version &allow-other-keys)
-  "Operate does three things:
+(with-upgradability ()
+  (defgeneric* (operate) (operation component &key &allow-other-keys))
+  (define-convenience-action-methods
+      operate (operation component &key)
+      :operation-initargs t ;; backward-compatibility with ASDF1. Yuck.
+      :if-no-component (error 'missing-component :requires component))
+
+  (defvar *systems-being-operated* nil
+    "A boolean indicating that some systems are being operated on")
+
+  (defmethod operate :around (operation component
+                              &key verbose
+                                (on-warnings *compile-file-warnings-behaviour*)
+                                (on-failure *compile-file-failure-behaviour*) &allow-other-keys)
+    (declare (ignorable operation component))
+    ;; Setup proper bindings around any operate call.
+    (with-system-definitions ()
+      (let* ((*verbose-out* (and verbose *standard-output*))
+             (*compile-file-warnings-behaviour* on-warnings)
+             (*compile-file-failure-behaviour* on-failure))
+        (call-next-method))))
+
+  (defmethod operate ((operation operation) (component component)
+                      &rest args &key version &allow-other-keys)
+    "Operate does three things:
 
 1. It creates an instance of OPERATION-CLASS using any keyword parameters as initargs.
 2. It finds the  asdf-system specified by SYSTEM (possibly loading it from disk).
@@ -6961,121 +7269,114 @@
   :ALL to force all systems including other systems we depend on to be rebuilt (resp. not).
   (SYSTEM1 SYSTEM2 ... SYSTEMN) to force systems named in a given list
 :FORCE has precedence over :FORCE-NOT; builtin systems cannot be forced."
-  (let* (;; I'd like to remove-plist-keys :force :force-not :verbose,
-         ;; but swank.asd relies on :force (!).
-         (systems-being-operated *systems-being-operated*)
-         (*systems-being-operated* (or systems-being-operated (make-hash-table :test 'equal)))
-         (system (component-system component)))
-    (setf (gethash (coerce-name system) *systems-being-operated*) system)
-    (unless (version-satisfies component version)
-      (error 'missing-component-of-version :requires component :version version))
-    ;; Before we operate on any system, make sure ASDF is up-to-date,
-    ;; for if an upgrade is ever attempted at any later time, there may be BIG trouble.
-    (unless systems-being-operated
-      (let ((operation-name (reify-symbol (type-of operation)))
-            (component-path (component-find-path component)))
-        (when (upgrade-asdf)
-          ;; If we were upgraded, restart OPERATE the hardest of ways, for
-          ;; its function may have been redefined, its symbol uninterned, its package deleted.
-          (return-from operate
-            (apply (find-symbol* 'operate :asdf)
-                   (unreify-symbol operation-name)
-                   component-path args)))))
-    (let ((plan (apply 'traverse operation system args)))
-      (perform-plan plan)
-      (values operation plan))))
-
-(defun* oos (operation component &rest args &key &allow-other-keys)
-  (apply 'operate operation component args))
-
-(setf (documentation 'oos 'function)
-      (format nil "Short for _operate on system_ and an alias for the OPERATE function.~%~%~a"
-              (documentation 'operate 'function)))
+    (let* (;; I'd like to remove-plist-keys :force :force-not :verbose,
+           ;; but swank.asd relies on :force (!).
+           (systems-being-operated *systems-being-operated*)
+           (*systems-being-operated* (or systems-being-operated (make-hash-table :test 'equal)))
+           (system (component-system component)))
+      (setf (gethash (coerce-name system) *systems-being-operated*) system)
+      (unless (version-satisfies component version)
+        (error 'missing-component-of-version :requires component :version version))
+      ;; Before we operate on any system, make sure ASDF is up-to-date,
+      ;; for if an upgrade is ever attempted at any later time, there may be BIG trouble.
+      (unless systems-being-operated
+        (let ((operation-name (reify-symbol (type-of operation)))
+              (component-path (component-find-path component)))
+          (when (upgrade-asdf)
+            ;; If we were upgraded, restart OPERATE the hardest of ways, for
+            ;; its function may have been redefined, its symbol uninterned, its package deleted.
+            (return-from operate
+              (apply (find-symbol* 'operate :asdf)
+                     (unreify-symbol operation-name)
+                     component-path args)))))
+      (let ((plan (apply 'traverse operation system args)))
+        (perform-plan plan)
+        (values operation plan))))
+
+  (defun oos (operation component &rest args &key &allow-other-keys)
+    (apply 'operate operation component args))
+
+  (setf (documentation 'oos 'function)
+        (format nil "Short for _operate on system_ and an alias for the OPERATE function.~%~%~a"
+                (documentation 'operate 'function))))
 
 
 ;;;; Common operations
-
-(defvar *load-system-operation* 'load-op
-  "Operation used by ASDF:LOAD-SYSTEM. By default, ASDF:LOAD-OP.
+(with-upgradability ()
+  (defvar *load-system-operation* 'load-op
+    "Operation used by ASDF:LOAD-SYSTEM. By default, ASDF:LOAD-OP.
 You may override it with e.g. ASDF:LOAD-FASL-OP from asdf-bundle,
 or ASDF:LOAD-SOURCE-OP if your fasl loading is somehow broken.
 
 This may change in the future as we will implement component-based strategy
 for how to load or compile stuff")
 
-(defun* build-system (system &rest keys)
-  "Shorthand for `(operate 'asdf:build-op system)`."
-  (apply 'operate 'build-op system keys)
-  t)
-
-(defun* load-system (system &rest keys &key force force-not verbose version &allow-other-keys)
-  "Shorthand for `(operate 'asdf:load-op system)`. See OPERATE for details."
-  (declare (ignore force force-not verbose version))
-  (apply 'operate *load-system-operation* system keys)
-  t)
-
-(defun* load-systems (&rest systems)
-  "Loading multiple systems at once."
-  (map () 'load-system systems))
-
-(defun* compile-system (system &rest args &key force force-not verbose version &allow-other-keys)
-  "Shorthand for `(asdf:operate 'asdf:compile-op system)`. See OPERATE for details."
-  (declare (ignore force force-not verbose version))
-  (apply 'operate 'compile-op system args)
-  t)
-
-(defun* test-system (system &rest args &key force force-not verbose version &allow-other-keys)
-  "Shorthand for `(asdf:operate 'asdf:test-op system)`. See OPERATE for details."
-  (declare (ignore force force-not verbose version))
-  (apply 'operate 'test-op system args)
-  t)
+  (defun build-system (system &rest keys)
+    "Shorthand for `(operate 'asdf:build-op system)`."
+    (apply 'operate 'build-op system keys)
+    t)
+
+  (defun load-system (system &rest keys &key force force-not verbose version &allow-other-keys)
+    "Shorthand for `(operate 'asdf:load-op system)`. See OPERATE for details."
+    (declare (ignore force force-not verbose version))
+    (apply 'operate *load-system-operation* system keys)
+    t)
+
+  (defun load-systems (&rest systems)
+    "Loading multiple systems at once."
+    (map () 'load-system systems))
+
+  (defun compile-system (system &rest args &key force force-not verbose version &allow-other-keys)
+    "Shorthand for `(asdf:operate 'asdf:compile-op system)`. See OPERATE for details."
+    (declare (ignore force force-not verbose version))
+    (apply 'operate 'compile-op system args)
+    t)
+
+  (defun test-system (system &rest args &key force force-not verbose version &allow-other-keys)
+    "Shorthand for `(asdf:operate 'asdf:test-op system)`. See OPERATE for details."
+    (declare (ignore force force-not verbose version))
+    (apply 'operate 'test-op system args)
+    t))
 
 
 ;;;; Define require-system, to be hooked into CL:REQUIRE when possible,
 ;; i.e. for ABCL, CLISP, ClozureCL, CMUCL, ECL, MKCL and SBCL
+(with-upgradability ()
+  (defun component-loaded-p (c)
+    (action-already-done-p nil (make-instance 'load-op) (find-component c ())))
 
-(defun* component-loaded-p (c)
-  (action-already-done-p nil (make-instance 'load-op) (find-component c ())))
-
-(defun* already-loaded-systems ()
-  (remove-if-not 'component-loaded-p (registered-systems)))
+  (defun already-loaded-systems ()
+    (remove-if-not 'component-loaded-p (registered-systems)))
 
-(defun* require-system (s &rest keys &key &allow-other-keys)
-  (apply 'load-system s :force-not (already-loaded-systems) keys))
+  (defun require-system (s &rest keys &key &allow-other-keys)
+    (apply 'load-system s :force-not (already-loaded-systems) keys))
 
-(defun* module-provide-asdf (name)
-  (handler-bind
-      ((style-warning #'muffle-warning)
-       (missing-component (constantly nil))
-       (error #'(lambda (e)
-                  (format *error-output* (compatfmt "~@<ASDF could not load ~(~A~) because ~A.~@:>~%")
-                          name e))))
-    (let ((*verbose-out* (make-broadcast-stream))
-          (system (find-system (string-downcase name) nil)))
-      (when system
-        (require-system system :verbose nil)
-        t))))
+  (defun module-provide-asdf (name)
+    (handler-bind
+        ((style-warning #'muffle-warning)
+         (missing-component (constantly nil))
+         (error #'(lambda (e)
+                    (format *error-output* (compatfmt "~@<ASDF could not load ~(~A~) because ~A.~@:>~%")
+                            name e))))
+      (let ((*verbose-out* (make-broadcast-stream))
+            (system (find-system (string-downcase name) nil)))
+        (when system
+          (require-system system :verbose nil)
+          t)))))
 
 
 ;;;; Some upgrade magic
+(with-upgradability ()
+  (defun restart-upgraded-asdf ()
+    ;; If we're in the middle of something, restart it.
+    (when *systems-being-defined*
+      (let ((l (loop :for name :being :the :hash-keys :of *systems-being-defined* :collect name)))
+        (clrhash *systems-being-defined*)
+        (dolist (s l) (find-system s nil)))))
+
+  (pushnew 'restart-upgraded-asdf *post-upgrade-restart-hook*))
 
-(defun* reset-asdf-systems ()
-  (let ((asdf (find-system :asdf)))
-    (setf (component-version asdf) (asdf-version))
-    ;; Invalidate all systems but ASDF itself.
-    (setf *defined-systems* (make-defined-systems-table))
-    (register-system asdf)
-    (load-system asdf))) ;; re-load ourselves the right way
-
-(defun* restart-upgraded-asdf ()
-  ;; If we're in the middle of something, restart it.
-  (when *systems-being-defined*
-    (let ((l (loop :for name :being :the :hash-keys :of *systems-being-defined* :collect name)))
-      (clrhash *systems-being-defined*)
-      (dolist (s l) (find-system s nil)))))
 
-(pushnew 'reset-asdf-systems *post-upgrade-cleanup-hook*)
-(pushnew 'restart-upgraded-asdf *post-upgrade-restart-hook*)
 ;;;; ---------------------------------------------------------------------------
 ;;;; asdf-output-translations
 
@@ -7100,295 +7401,297 @@
    ))
 (in-package :asdf/output-translations)
 
-(when-upgrade () (undefine-function '(setf output-translations)))
+(when-upgrading () (undefine-function '(setf output-translations)))
 
-(define-condition invalid-output-translation (invalid-configuration warning)
-  ((format :initform (compatfmt "~@<Invalid asdf output-translation ~S~@[ in ~S~]~@{ ~@?~}~@:>"))))
+(with-upgradability ()
+  (define-condition invalid-output-translation (invalid-configuration warning)
+    ((format :initform (compatfmt "~@<Invalid asdf output-translation ~S~@[ in ~S~]~@{ ~@?~}~@:>"))))
 
-(defvar *output-translations* ()
-  "Either NIL (for uninitialized), or a list of one element,
+  (defvar *output-translations* ()
+    "Either NIL (for uninitialized), or a list of one element,
 said element itself being a sorted list of mappings.
 Each mapping is a pair of a source pathname and destination pathname,
 and the order is by decreasing length of namestring of the source pathname.")
 
-(defun* output-translations ()
-  (car *output-translations*))
+  (defun output-translations ()
+    (car *output-translations*))
 
-(defun* set-output-translations (new-value)
-  (setf *output-translations*
-        (list
-         (stable-sort (copy-list new-value) #'>
-                      :key #'(lambda (x)
-                               (etypecase (car x)
-                                 ((eql t) -1)
-                                 (pathname
-                                  (let ((directory (pathname-directory (car x))))
-                                    (if (listp directory) (length directory) 0))))))))
-  new-value)
-(defsetf output-translations set-output-translations) ; works with gcl 2.6
-
-(defun* output-translations-initialized-p ()
-  (and *output-translations* t))
-
-(defun* clear-output-translations ()
-  "Undoes any initialization of the output translations."
-  (setf *output-translations* '())
-  (values))
-(register-clear-configuration-hook 'clear-output-translations)
-
-(defun* validate-output-translations-directive (directive)
-  (or (member directive '(:enable-user-cache :disable-cache nil))
-      (and (consp directive)
-           (or (and (length=n-p directive 2)
-                    (or (and (eq (first directive) :include)
-                             (typep (second directive) '(or string pathname null)))
-                        (and (location-designator-p (first directive))
-                             (or (location-designator-p (second directive))
-                                 (location-function-p (second directive))))))
-               (and (length=n-p directive 1)
-                    (location-designator-p (first directive)))))))
-
-(defun* validate-output-translations-form (form &key location)
-  (validate-configuration-form
-   form
-   :output-translations
-   'validate-output-translations-directive
-   :location location :invalid-form-reporter 'invalid-output-translation))
-
-(defun* validate-output-translations-file (file)
-  (validate-configuration-file
-   file 'validate-output-translations-form :description "output translations"))
-
-(defun* validate-output-translations-directory (directory)
-  (validate-configuration-directory
-   directory :output-translations 'validate-output-translations-directive
-   :invalid-form-reporter 'invalid-output-translation))
+  (defun set-output-translations (new-value)
+    (setf *output-translations*
+          (list
+           (stable-sort (copy-list new-value) #'>
+                        :key #'(lambda (x)
+                                 (etypecase (car x)
+                                   ((eql t) -1)
+                                   (pathname
+                                    (let ((directory (pathname-directory (car x))))
+                                      (if (listp directory) (length directory) 0))))))))
+    new-value)
+  (defsetf output-translations set-output-translations) ; works with gcl 2.6
+
+  (defun output-translations-initialized-p ()
+    (and *output-translations* t))
+
+  (defun clear-output-translations ()
+    "Undoes any initialization of the output translations."
+    (setf *output-translations* '())
+    (values))
+  (register-clear-configuration-hook 'clear-output-translations)
+
+  (defun validate-output-translations-directive (directive)
+    (or (member directive '(:enable-user-cache :disable-cache nil))
+        (and (consp directive)
+             (or (and (length=n-p directive 2)
+                      (or (and (eq (first directive) :include)
+                               (typep (second directive) '(or string pathname null)))
+                          (and (location-designator-p (first directive))
+                               (or (location-designator-p (second directive))
+                                   (location-function-p (second directive))))))
+                 (and (length=n-p directive 1)
+                      (location-designator-p (first directive)))))))
+
+  (defun validate-output-translations-form (form &key location)
+    (validate-configuration-form
+     form
+     :output-translations
+     'validate-output-translations-directive
+     :location location :invalid-form-reporter 'invalid-output-translation))
+
+  (defun validate-output-translations-file (file)
+    (validate-configuration-file
+     file 'validate-output-translations-form :description "output translations"))
+
+  (defun validate-output-translations-directory (directory)
+    (validate-configuration-directory
+     directory :output-translations 'validate-output-translations-directive
+               :invalid-form-reporter 'invalid-output-translation))
 
-(defun* parse-output-translations-string (string &key location)
-  (cond
-    ((or (null string) (equal string ""))
-     '(:output-translations :inherit-configuration))
-    ((not (stringp string))
-     (error (compatfmt "~@<Environment string isn't: ~3i~_~S~@:>") string))
-    ((eql (char string 0) #\")
-     (parse-output-translations-string (read-from-string string) :location location))
-    ((eql (char string 0) #\()
-     (validate-output-translations-form (read-from-string string) :location location))
-    (t
-     (loop
-      :with inherit = nil
-      :with directives = ()
-      :with start = 0
-      :with end = (length string)
-      :with source = nil
-      :with separator = (inter-directory-separator)
-      :for i = (or (position separator string :start start) end) :do
-      (let ((s (subseq string start i)))
-        (cond
-          (source
-           (push (list source (if (equal "" s) nil s)) directives)
-           (setf source nil))
-          ((equal "" s)
-           (when inherit
-             (error (compatfmt "~@<Only one inherited configuration allowed: ~3i~_~S~@:>")
-                    string))
-           (setf inherit t)
-           (push :inherit-configuration directives))
-          (t
-           (setf source s)))
-        (setf start (1+ i))
-        (when (> start end)
-          (when source
-            (error (compatfmt "~@<Uneven number of components in source to destination mapping: ~3i~_~S~@:>")
-                   string))
-          (unless inherit
-            (push :ignore-inherited-configuration directives))
-          (return `(:output-translations ,@(nreverse directives)))))))))
-
-(defparameter *default-output-translations*
-  '(environment-output-translations
-    user-output-translations-pathname
-    user-output-translations-directory-pathname
-    system-output-translations-pathname
-    system-output-translations-directory-pathname))
+  (defun parse-output-translations-string (string &key location)
+    (cond
+      ((or (null string) (equal string ""))
+       '(:output-translations :inherit-configuration))
+      ((not (stringp string))
+       (error (compatfmt "~@<Environment string isn't: ~3i~_~S~@:>") string))
+      ((eql (char string 0) #\")
+       (parse-output-translations-string (read-from-string string) :location location))
+      ((eql (char string 0) #\()
+       (validate-output-translations-form (read-from-string string) :location location))
+      (t
+       (loop
+         :with inherit = nil
+         :with directives = ()
+         :with start = 0
+         :with end = (length string)
+         :with source = nil
+         :with separator = (inter-directory-separator)
+         :for i = (or (position separator string :start start) end) :do
+           (let ((s (subseq string start i)))
+             (cond
+               (source
+                (push (list source (if (equal "" s) nil s)) directives)
+                (setf source nil))
+               ((equal "" s)
+                (when inherit
+                  (error (compatfmt "~@<Only one inherited configuration allowed: ~3i~_~S~@:>")
+                         string))
+                (setf inherit t)
+                (push :inherit-configuration directives))
+               (t
+                (setf source s)))
+             (setf start (1+ i))
+             (when (> start end)
+               (when source
+                 (error (compatfmt "~@<Uneven number of components in source to destination mapping: ~3i~_~S~@:>")
+                        string))
+               (unless inherit
+                 (push :ignore-inherited-configuration directives))
+               (return `(:output-translations ,@(nreverse directives)))))))))
+
+  (defparameter *default-output-translations*
+    '(environment-output-translations
+      user-output-translations-pathname
+      user-output-translations-directory-pathname
+      system-output-translations-pathname
+      system-output-translations-directory-pathname))
 
-(defun* wrapping-output-translations ()
-  `(:output-translations
+  (defun wrapping-output-translations ()
+    `(:output-translations
     ;; Some implementations have precompiled ASDF systems,
     ;; so we must disable translations for implementation paths.
-    #+(or #|clozure|# ecl mkcl sbcl)
-    ,@(let ((h (resolve-symlinks* (lisp-implementation-directory))))
-        (when h `(((,h ,*wild-path*) ()))))
-    #+mkcl (,(translate-logical-pathname "CONTRIB:") ())
-    ;; All-import, here is where we want user stuff to be:
-    :inherit-configuration
-    ;; These are for convenience, and can be overridden by the user:
-    #+abcl (#p"/___jar___file___root___/**/*.*" (:user-cache #p"**/*.*"))
-    #+abcl (#p"jar:file:/**/*.jar!/**/*.*" (:function translate-jar-pathname))
-    ;; We enable the user cache by default, and here is the place we do:
-    :enable-user-cache))
-
-(defparameter *output-translations-file* (parse-unix-namestring "asdf-output-translations.conf"))
-(defparameter *output-translations-directory* (parse-unix-namestring "asdf-output-translations.conf.d/"))
-
-(defun* user-output-translations-pathname (&key (direction :input))
-  (in-user-configuration-directory *output-translations-file* :direction direction))
-(defun* system-output-translations-pathname (&key (direction :input))
-  (in-system-configuration-directory *output-translations-file* :direction direction))
-(defun* user-output-translations-directory-pathname (&key (direction :input))
-  (in-user-configuration-directory *output-translations-directory* :direction direction))
-(defun* system-output-translations-directory-pathname (&key (direction :input))
-  (in-system-configuration-directory *output-translations-directory* :direction direction))
-(defun* environment-output-translations ()
-  (getenv "ASDF_OUTPUT_TRANSLATIONS"))
-
-(defgeneric* process-output-translations (spec &key inherit collect))
-
-(defun* inherit-output-translations (inherit &key collect)
-  (when inherit
-    (process-output-translations (first inherit) :collect collect :inherit (rest inherit))))
-
-(defun* (process-output-translations-directive) (directive &key inherit collect)
-  (if (atom directive)
-      (ecase directive
-        ((:enable-user-cache)
-         (process-output-translations-directive '(t :user-cache) :collect collect))
-        ((:disable-cache)
-         (process-output-translations-directive '(t t) :collect collect))
-        ((:inherit-configuration)
-         (inherit-output-translations inherit :collect collect))
-        ((:ignore-inherited-configuration :ignore-invalid-entries nil)
-         nil))
-      (let ((src (first directive))
-            (dst (second directive)))
-        (if (eq src :include)
-            (when dst
-              (process-output-translations (pathname dst) :inherit nil :collect collect))
-            (when src
-              (let ((trusrc (or (eql src t)
-                                (let ((loc (resolve-location src :ensure-directory t :wilden t)))
-                                  (if (absolute-pathname-p loc) (resolve-symlinks* loc) loc)))))
-                (cond
-                  ((location-function-p dst)
-                   (funcall collect
-                            (list trusrc
-                                  (if (symbolp (second dst))
-                                      (fdefinition (second dst))
-                                      (eval (second dst))))))
-                  ((eq dst t)
-                   (funcall collect (list trusrc t)))
-                  (t
-                   (let* ((trudst (if dst
-                                      (resolve-location dst :ensure-directory t :wilden t)
-                                      trusrc)))
-                     (funcall collect (list trudst t))
-                     (funcall collect (list trusrc trudst)))))))))))
-
-(defmethod process-output-translations ((x symbol) &key
-                                        (inherit *default-output-translations*)
-                                        collect)
-  (process-output-translations (funcall x) :inherit inherit :collect collect))
-(defmethod process-output-translations ((pathname #-gcl2.6 pathname #+gcl2.6 t) &key inherit collect)
-  (cond
-    ((directory-pathname-p pathname)
-     (process-output-translations (validate-output-translations-directory pathname)
-                                  :inherit inherit :collect collect))
-    ((probe-file* pathname :truename *resolve-symlinks*)
-     (process-output-translations (validate-output-translations-file pathname)
-                                  :inherit inherit :collect collect))
-    (t
-     (inherit-output-translations inherit :collect collect))))
-(defmethod process-output-translations ((string string) &key inherit collect)
-  (process-output-translations (parse-output-translations-string string)
-                               :inherit inherit :collect collect))
-(defmethod process-output-translations ((x null) &key inherit collect)
-  (declare (ignorable x))
-  (inherit-output-translations inherit :collect collect))
-(defmethod process-output-translations ((form cons) &key inherit collect)
-  (dolist (directive (cdr (validate-output-translations-form form)))
-    (process-output-translations-directive directive :inherit inherit :collect collect)))
-
-(defun* compute-output-translations (&optional parameter)
-  "read the configuration, return it"
-  (remove-duplicates
-   (while-collecting (c)
-     (inherit-output-translations
-      `(wrapping-output-translations ,parameter ,@*default-output-translations*) :collect #'c))
-   :test 'equal :from-end t))
+      #+(or #|clozure|# ecl mkcl sbcl)
+      ,@(let ((h (resolve-symlinks* (lisp-implementation-directory))))
+          (when h `(((,h ,*wild-path*) ()))))
+      #+mkcl (,(translate-logical-pathname "CONTRIB:") ())
+      ;; All-import, here is where we want user stuff to be:
+      :inherit-configuration
+      ;; These are for convenience, and can be overridden by the user:
+      #+abcl (#p"/___jar___file___root___/**/*.*" (:user-cache #p"**/*.*"))
+      #+abcl (#p"jar:file:/**/*.jar!/**/*.*" (:function translate-jar-pathname))
+      ;; We enable the user cache by default, and here is the place we do:
+      :enable-user-cache))
+
+  (defparameter *output-translations-file* (parse-unix-namestring "asdf-output-translations.conf"))
+  (defparameter *output-translations-directory* (parse-unix-namestring "asdf-output-translations.conf.d/"))
+
+  (defun user-output-translations-pathname (&key (direction :input))
+    (in-user-configuration-directory *output-translations-file* :direction direction))
+  (defun system-output-translations-pathname (&key (direction :input))
+    (in-system-configuration-directory *output-translations-file* :direction direction))
+  (defun user-output-translations-directory-pathname (&key (direction :input))
+    (in-user-configuration-directory *output-translations-directory* :direction direction))
+  (defun system-output-translations-directory-pathname (&key (direction :input))
+    (in-system-configuration-directory *output-translations-directory* :direction direction))
+  (defun environment-output-translations ()
+    (getenv "ASDF_OUTPUT_TRANSLATIONS"))
+
+  (defgeneric process-output-translations (spec &key inherit collect))
+
+  (defun inherit-output-translations (inherit &key collect)
+    (when inherit
+      (process-output-translations (first inherit) :collect collect :inherit (rest inherit))))
+
+  (defun* (process-output-translations-directive) (directive &key inherit collect)
+    (if (atom directive)
+        (ecase directive
+          ((:enable-user-cache)
+           (process-output-translations-directive '(t :user-cache) :collect collect))
+          ((:disable-cache)
+           (process-output-translations-directive '(t t) :collect collect))
+          ((:inherit-configuration)
+           (inherit-output-translations inherit :collect collect))
+          ((:ignore-inherited-configuration :ignore-invalid-entries nil)
+           nil))
+        (let ((src (first directive))
+              (dst (second directive)))
+          (if (eq src :include)
+              (when dst
+                (process-output-translations (pathname dst) :inherit nil :collect collect))
+              (when src
+                (let ((trusrc (or (eql src t)
+                                  (let ((loc (resolve-location src :ensure-directory t :wilden t)))
+                                    (if (absolute-pathname-p loc) (resolve-symlinks* loc) loc)))))
+                  (cond
+                    ((location-function-p dst)
+                     (funcall collect
+                              (list trusrc
+                                    (if (symbolp (second dst))
+                                        (fdefinition (second dst))
+                                        (eval (second dst))))))
+                    ((eq dst t)
+                     (funcall collect (list trusrc t)))
+                    (t
+                     (let* ((trudst (if dst
+                                        (resolve-location dst :ensure-directory t :wilden t)
+                                        trusrc)))
+                       (funcall collect (list trudst t))
+                       (funcall collect (list trusrc trudst)))))))))))
+
+  (defmethod process-output-translations ((x symbol) &key
+                                                       (inherit *default-output-translations*)
+                                                       collect)
+    (process-output-translations (funcall x) :inherit inherit :collect collect))
+  (defmethod process-output-translations ((pathname #-gcl2.6 pathname #+gcl2.6 t) &key inherit collect)
+    (cond
+      ((directory-pathname-p pathname)
+       (process-output-translations (validate-output-translations-directory pathname)
+                                    :inherit inherit :collect collect))
+      ((probe-file* pathname :truename *resolve-symlinks*)
+       (process-output-translations (validate-output-translations-file pathname)
+                                    :inherit inherit :collect collect))
+      (t
+       (inherit-output-translations inherit :collect collect))))
+  (defmethod process-output-translations ((string string) &key inherit collect)
+    (process-output-translations (parse-output-translations-string string)
+                                 :inherit inherit :collect collect))
+  (defmethod process-output-translations ((x null) &key inherit collect)
+    (declare (ignorable x))
+    (inherit-output-translations inherit :collect collect))
+  (defmethod process-output-translations ((form cons) &key inherit collect)
+    (dolist (directive (cdr (validate-output-translations-form form)))
+      (process-output-translations-directive directive :inherit inherit :collect collect)))
+
+  (defun compute-output-translations (&optional parameter)
+    "read the configuration, return it"
+    (remove-duplicates
+     (while-collecting (c)
+       (inherit-output-translations
+        `(wrapping-output-translations ,parameter ,@*default-output-translations*) :collect #'c))
+     :test 'equal :from-end t))
 
-(defvar *output-translations-parameter* nil)
+  (defvar *output-translations-parameter* nil)
 
-(defun* initialize-output-translations (&optional (parameter *output-translations-parameter*))
-  "read the configuration, initialize the internal configuration variable,
+  (defun initialize-output-translations (&optional (parameter *output-translations-parameter*))
+    "read the configuration, initialize the internal configuration variable,
 return the configuration"
-  (setf *output-translations-parameter* parameter
-        (output-translations) (compute-output-translations parameter)))
+    (setf *output-translations-parameter* parameter
+          (output-translations) (compute-output-translations parameter)))
 
-(defun* disable-output-translations ()
-  "Initialize output translations in a way that maps every file to itself,
+  (defun disable-output-translations ()
+    "Initialize output translations in a way that maps every file to itself,
 effectively disabling the output translation facility."
-  (initialize-output-translations
-   '(:output-translations :disable-cache :ignore-inherited-configuration)))
+    (initialize-output-translations
+     '(:output-translations :disable-cache :ignore-inherited-configuration)))
+
+  ;; checks an initial variable to see whether the state is initialized
+  ;; or cleared. In the former case, return current configuration; in
+  ;; the latter, initialize.  ASDF will call this function at the start
+  ;; of (asdf:find-system).
+  (defun ensure-output-translations ()
+    (if (output-translations-initialized-p)
+        (output-translations)
+        (initialize-output-translations)))
+
+  (defun* (apply-output-translations) (path)
+    #+cormanlisp (resolve-symlinks* path) #-cormanlisp
+                                          (etypecase path
+                                            (logical-pathname
+                                             path)
+                                            ((or pathname string)
+                                             (ensure-output-translations)
+                                             (loop* :with p = (resolve-symlinks* path)
+                                                    :for (source destination) :in (car *output-translations*)
+                                                    :for root = (when (or (eq source t)
+                                                                          (and (pathnamep source)
+                                                                               (not (absolute-pathname-p source))))
+                                                                  (pathname-root p))
+                                                    :for absolute-source = (cond
+                                                                             ((eq source t) (wilden root))
+                                                                             (root (merge-pathnames* source root))
+                                                                             (t source))
+                                                    :when (or (eq source t) (pathname-match-p p absolute-source))
+                                                    :return (translate-pathname* p absolute-source destination root source)
+                                                    :finally (return p)))))
+
+  ;; Hook into asdf/driver's output-translation mechanism
+  (setf *output-translation-function* 'apply-output-translations)
+
+  #+abcl
+  (defun translate-jar-pathname (source wildcard)
+    (declare (ignore wildcard))
+    (flet ((normalize-device (pathname)
+             (if (find :windows *features*)
+                 pathname
+                 (make-pathname :defaults pathname :device :unspecific))))
+      (let* ((jar
+               (pathname (first (pathname-device source))))
+             (target-root-directory-namestring
+               (format nil "/___jar___file___root___/~@[~A/~]"
+                       (and (find :windows *features*)
+                            (pathname-device jar))))
+             (relative-source
+               (relativize-pathname-directory source))
+             (relative-jar
+               (relativize-pathname-directory (ensure-directory-pathname jar)))
+             (target-root-directory
+               (normalize-device
+                (pathname-directory-pathname
+                 (parse-namestring target-root-directory-namestring))))
+             (target-root
+               (merge-pathnames* relative-jar target-root-directory))
+             (target
+               (merge-pathnames* relative-source target-root)))
+        (normalize-device (apply-output-translations target))))))
 
-;; checks an initial variable to see whether the state is initialized
-;; or cleared. In the former case, return current configuration; in
-;; the latter, initialize.  ASDF will call this function at the start
-;; of (asdf:find-system).
-(defun* ensure-output-translations ()
-  (if (output-translations-initialized-p)
-      (output-translations)
-      (initialize-output-translations)))
-
-(defun* (apply-output-translations) (path)
-  #+cormanlisp (resolve-symlinks* path) #-cormanlisp
-  (etypecase path
-    (logical-pathname
-     path)
-    ((or pathname string)
-     (ensure-output-translations)
-     (loop* :with p = (resolve-symlinks* path)
-       :for (source destination) :in (car *output-translations*)
-       :for root = (when (or (eq source t)
-                             (and (pathnamep source)
-                                  (not (absolute-pathname-p source))))
-                     (pathname-root p))
-       :for absolute-source = (cond
-                                ((eq source t) (wilden root))
-                                (root (merge-pathnames* source root))
-                                (t source))
-       :when (or (eq source t) (pathname-match-p p absolute-source))
-       :return (translate-pathname* p absolute-source destination root source)
-       :finally (return p)))))
-
-;; Hook into asdf/driver's output-translation mechanism
-(setf *output-translation-function* 'apply-output-translations)
-
-#+abcl
-(defun* translate-jar-pathname (source wildcard)
-  (declare (ignore wildcard))
-  (flet ((normalize-device (pathname)
-           (if (find :windows *features*)
-               pathname
-               (make-pathname :defaults pathname :device :unspecific))))
-    (let* ((jar
-             (pathname (first (pathname-device source))))
-           (target-root-directory-namestring
-             (format nil "/___jar___file___root___/~@[~A/~]"
-                     (and (find :windows *features*)
-                          (pathname-device jar))))
-           (relative-source
-             (relativize-pathname-directory source))
-           (relative-jar
-             (relativize-pathname-directory (ensure-directory-pathname jar)))
-           (target-root-directory
-             (normalize-device
-              (pathname-directory-pathname
-               (parse-namestring target-root-directory-namestring))))
-           (target-root
-             (merge-pathnames* relative-jar target-root-directory))
-           (target
-             (merge-pathnames* relative-source target-root)))
-      (normalize-device (apply-output-translations target)))))
 ;;;; -----------------------------------------------------------------
 ;;;; Source Registry Configuration, by Francois-Rene Rideau
 ;;;; See the Manual and https://bugs.launchpad.net/asdf/+bug/485918
@@ -7415,292 +7718,295 @@
    #:sysdef-source-registry-search))
 (in-package :asdf/source-registry)
 
-(define-condition invalid-source-registry (invalid-configuration warning)
-  ((format :initform (compatfmt "~@<Invalid source registry ~S~@[ in ~S~]~@{ ~@?~}~@:>"))))
-
-;; Using ack 1.2 exclusions
-(defvar *default-source-registry-exclusions*
-  '(".bzr" ".cdv"
-    ;; "~.dep" "~.dot" "~.nib" "~.plst" ; we don't support ack wildcards
-    ".git" ".hg" ".pc" ".svn" "CVS" "RCS" "SCCS" "_darcs"
-    "_sgbak" "autom4te.cache" "cover_db" "_build"
-    "debian")) ;; debian often builds stuff under the debian directory... BAD.
+(with-upgradability ()
+  (define-condition invalid-source-registry (invalid-configuration warning)
+    ((format :initform (compatfmt "~@<Invalid source registry ~S~@[ in ~S~]~@{ ~@?~}~@:>"))))
+
+  ;; Using ack 1.2 exclusions
+  (defvar *default-source-registry-exclusions*
+    '(".bzr" ".cdv"
+      ;; "~.dep" "~.dot" "~.nib" "~.plst" ; we don't support ack wildcards
+      ".git" ".hg" ".pc" ".svn" "CVS" "RCS" "SCCS" "_darcs"
+      "_sgbak" "autom4te.cache" "cover_db" "_build"
+      "debian")) ;; debian often builds stuff under the debian directory... BAD.
 
-(defvar *source-registry-exclusions* *default-source-registry-exclusions*)
+  (defvar *source-registry-exclusions* *default-source-registry-exclusions*)
 
-(defvar *source-registry* nil
-  "Either NIL (for uninitialized), or an equal hash-table, mapping
+  (defvar *source-registry* nil
+    "Either NIL (for uninitialized), or an equal hash-table, mapping
 system names to pathnames of .asd files")
 
-(defun* source-registry-initialized-p ()
-  (typep *source-registry* 'hash-table))
+  (defun source-registry-initialized-p ()
+    (typep *source-registry* 'hash-table))
 
-(defun* clear-source-registry ()
-  "Undoes any initialization of the source registry."
-  (setf *source-registry* nil)
-  (values))
-(register-clear-configuration-hook 'clear-source-registry)
-
-(defparameter *wild-asd*
-  (make-pathname* :directory nil :name *wild* :type "asd"))
-
-(defun* directory-asd-files (directory)
-  (directory-files directory *wild-asd*))
-
-(defun* collect-asds-in-directory (directory collect)
-  (map () collect (directory-asd-files directory)))
-
-(defun* collect-sub*directories-asd-files
-    (directory &key (exclude *default-source-registry-exclusions*) collect)
-  (collect-sub*directories
-   directory
-   (constantly t)
-   #'(lambda (x) (not (member (car (last (pathname-directory x))) exclude :test #'equal)))
-   #'(lambda (dir) (collect-asds-in-directory dir collect))))
-
-(defun* validate-source-registry-directive (directive)
-  (or (member directive '(:default-registry))
-      (and (consp directive)
-           (let ((rest (rest directive)))
-             (case (first directive)
-               ((:include :directory :tree)
-                (and (length=n-p rest 1)
-                     (location-designator-p (first rest))))
-               ((:exclude :also-exclude)
-                (every #'stringp rest))
-               ((:default-registry)
-                (null rest)))))))
-
-(defun* validate-source-registry-form (form &key location)
-  (validate-configuration-form
-   form :source-registry 'validate-source-registry-directive
-   :location location :invalid-form-reporter 'invalid-source-registry))
-
-(defun* validate-source-registry-file (file)
-  (validate-configuration-file
-   file 'validate-source-registry-form :description "a source registry"))
-
-(defun* validate-source-registry-directory (directory)
-  (validate-configuration-directory
-   directory :source-registry 'validate-source-registry-directive
-   :invalid-form-reporter 'invalid-source-registry))
+  (defun clear-source-registry ()
+    "Undoes any initialization of the source registry."
+    (setf *source-registry* nil)
+    (values))
+  (register-clear-configuration-hook 'clear-source-registry)
+
+  (defparameter *wild-asd*
+    (make-pathname* :directory nil :name *wild* :type "asd" :version :newest))
+
+  (defun directory-asd-files (directory)
+    (directory-files directory *wild-asd*))
+
+  (defun collect-asds-in-directory (directory collect)
+    (map () collect (directory-asd-files directory)))
+
+  (defun collect-sub*directories-asd-files
+      (directory &key (exclude *default-source-registry-exclusions*) collect)
+    (collect-sub*directories
+     directory
+     (constantly t)
+     #'(lambda (x &aux (l (car (last (pathname-directory x))))) (not (member l exclude :test #'equal)))
+     #'(lambda (dir) (collect-asds-in-directory dir collect))))
+
+  (defun validate-source-registry-directive (directive)
+    (or (member directive '(:default-registry))
+        (and (consp directive)
+             (let ((rest (rest directive)))
+               (case (first directive)
+                 ((:include :directory :tree)
+                  (and (length=n-p rest 1)
+                       (location-designator-p (first rest))))
+                 ((:exclude :also-exclude)
+                  (every #'stringp rest))
+                 ((:default-registry)
+                  (null rest)))))))
+
+  (defun validate-source-registry-form (form &key location)
+    (validate-configuration-form
+     form :source-registry 'validate-source-registry-directive
+          :location location :invalid-form-reporter 'invalid-source-registry))
+
+  (defun validate-source-registry-file (file)
+    (validate-configuration-file
+     file 'validate-source-registry-form :description "a source registry"))
+
+  (defun validate-source-registry-directory (directory)
+    (validate-configuration-directory
+     directory :source-registry 'validate-source-registry-directive
+               :invalid-form-reporter 'invalid-source-registry))
 
-(defun* parse-source-registry-string (string &key location)
-  (cond
-    ((or (null string) (equal string ""))
-     '(:source-registry :inherit-configuration))
-    ((not (stringp string))
-     (error (compatfmt "~@<Environment string isn't: ~3i~_~S~@:>") string))
-    ((find (char string 0) "\"(")
-     (validate-source-registry-form (read-from-string string) :location location))
-    (t
-     (loop
-      :with inherit = nil
-      :with directives = ()
-      :with start = 0
-      :with end = (length string)
-      :with separator = (inter-directory-separator)
-      :for pos = (position separator string :start start) :do
-      (let ((s (subseq string start (or pos end))))
-        (flet ((check (dir)
-                 (unless (absolute-pathname-p dir)
-                   (error (compatfmt "~@<source-registry string must specify absolute pathnames: ~3i~_~S~@:>") string))
-                 dir))
-          (cond
-            ((equal "" s) ; empty element: inherit
-             (when inherit
-               (error (compatfmt "~@<Only one inherited configuration allowed: ~3i~_~S~@:>")
-                      string))
-             (setf inherit t)
-             (push ':inherit-configuration directives))
-            ((string-suffix-p s "//") ;; TODO: allow for doubling of separator even outside Unix?
-             (push `(:tree ,(check (subseq s 0 (- (length s) 2)))) directives))
-            (t
-             (push `(:directory ,(check s)) directives))))
-        (cond
-          (pos
-           (setf start (1+ pos)))
-          (t
-           (unless inherit
-             (push '(:ignore-inherited-configuration) directives))
-           (return `(:source-registry ,@(nreverse directives))))))))))
-
-(defun* register-asd-directory (directory &key recurse exclude collect)
-  (if (not recurse)
-      (collect-asds-in-directory directory collect)
-      (collect-sub*directories-asd-files
-       directory :exclude exclude :collect collect)))
-
-(defparameter *default-source-registries*
-  '(environment-source-registry
-    user-source-registry
-    user-source-registry-directory
-    system-source-registry
-    system-source-registry-directory
-    default-source-registry))
-
-(defparameter *source-registry-file* (parse-unix-namestring "source-registry.conf"))
-(defparameter *source-registry-directory* (parse-unix-namestring "source-registry.conf.d/"))
-
-(defun* wrapping-source-registry ()
-  `(:source-registry
-    #+(or ecl sbcl) (:tree ,(resolve-symlinks* (lisp-implementation-directory)))
-    #+mkcl (:tree ,(translate-logical-pathname "CONTRIB:"))
-    :inherit-configuration
-    #+cmu (:tree #p"modules:")
-    #+scl (:tree #p"file://modules/")))
-(defun* default-source-registry ()
-  `(:source-registry
-    #+sbcl (:directory ,(subpathname (user-homedir-pathname) ".sbcl/systems/"))
-    ,@(loop :for dir :in
-        `(,@(when (os-unix-p)
-              `(,(or (getenv-absolute-directory "XDG_DATA_HOME")
-                     (subpathname (user-homedir-pathname) ".local/share/"))
-                ,@(or (getenv-absolute-directories "XDG_DATA_DIRS")
-                      '("/usr/local/share" "/usr/share"))))
-          ,@(when (os-windows-p)
-              (mapcar 'get-folder-path '(:local-appdata :appdata :common-appdata))))
-        :collect `(:directory ,(subpathname* dir "common-lisp/systems/"))
-        :collect `(:tree ,(subpathname* dir "common-lisp/source/")))
-    :inherit-configuration))
-(defun* user-source-registry (&key (direction :input))
-  (in-user-configuration-directory *source-registry-file* :direction direction))
-(defun* system-source-registry (&key (direction :input))
-  (in-system-configuration-directory *source-registry-file* :direction direction))
-(defun* user-source-registry-directory (&key (direction :input))
-  (in-user-configuration-directory *source-registry-directory* :direction direction))
-(defun* system-source-registry-directory (&key (direction :input))
-  (in-system-configuration-directory *source-registry-directory* :direction direction))
-(defun* environment-source-registry ()
-  (getenv "CL_SOURCE_REGISTRY"))
-
-(defgeneric* (process-source-registry) (spec &key inherit register))
-
-(defun* (inherit-source-registry) (inherit &key register)
-  (when inherit
-    (process-source-registry (first inherit) :register register :inherit (rest inherit))))
-
-(defun* (process-source-registry-directive) (directive &key inherit register)
-  (destructuring-bind (kw &rest rest) (if (consp directive) directive (list directive))
-    (ecase kw
-      ((:include)
-       (destructuring-bind (pathname) rest
-         (process-source-registry (resolve-location pathname) :inherit nil :register register)))
-      ((:directory)
-       (destructuring-bind (pathname) rest
-         (when pathname
-           (funcall register (resolve-location pathname :ensure-directory t)))))
-      ((:tree)
-       (destructuring-bind (pathname) rest
-         (when pathname
-           (funcall register (resolve-location pathname :ensure-directory t)
-                    :recurse t :exclude *source-registry-exclusions*))))
-      ((:exclude)
-       (setf *source-registry-exclusions* rest))
-      ((:also-exclude)
-       (appendf *source-registry-exclusions* rest))
-      ((:default-registry)
-       (inherit-source-registry '(default-source-registry) :register register))
-      ((:inherit-configuration)
-       (inherit-source-registry inherit :register register))
-      ((:ignore-inherited-configuration)
-       nil)))
-  nil)
-
-(defmethod process-source-registry ((x symbol) &key inherit register)
-  (process-source-registry (funcall x) :inherit inherit :register register))
-(defmethod process-source-registry ((pathname #-gcl2.6 pathname #+gcl2.6 t) &key inherit register)
-  (cond
-    ((directory-pathname-p pathname)
-     (let ((*here-directory* (resolve-symlinks* pathname)))
-       (process-source-registry (validate-source-registry-directory pathname)
-                                :inherit inherit :register register)))
-    ((probe-file* pathname :truename *resolve-symlinks*)
-     (let ((*here-directory* (pathname-directory-pathname pathname)))
-       (process-source-registry (validate-source-registry-file pathname)
-                                :inherit inherit :register register)))
-    (t
-     (inherit-source-registry inherit :register register))))
-(defmethod process-source-registry ((string string) &key inherit register)
-  (process-source-registry (parse-source-registry-string string)
-                           :inherit inherit :register register))
-(defmethod process-source-registry ((x null) &key inherit register)
-  (declare (ignorable x))
-  (inherit-source-registry inherit :register register))
-(defmethod process-source-registry ((form cons) &key inherit register)
-  (let ((*source-registry-exclusions* *default-source-registry-exclusions*))
-    (dolist (directive (cdr (validate-source-registry-form form)))
-      (process-source-registry-directive directive :inherit inherit :register register))))
-
-(defun* flatten-source-registry (&optional parameter)
-  (remove-duplicates
-   (while-collecting (collect)
-     (with-pathname-defaults () ;; be location-independent
-       (inherit-source-registry
-        `(wrapping-source-registry
-          ,parameter
-          ,@*default-source-registries*)
-        :register #'(lambda (directory &key recurse exclude)
-                      (collect (list directory :recurse recurse :exclude exclude))))))
-   :test 'equal :from-end t))
-
-;; Will read the configuration and initialize all internal variables.
-(defun* compute-source-registry (&optional parameter (registry *source-registry*))
-  (dolist (entry (flatten-source-registry parameter))
-    (destructuring-bind (directory &key recurse exclude) entry
-      (let* ((h (make-hash-table :test 'equal))) ; table to detect duplicates
-        (register-asd-directory
-         directory :recurse recurse :exclude exclude :collect
-         #'(lambda (asd)
-             (let* ((name (pathname-name asd))
-                    (name (if (typep asd 'logical-pathname)
-                              ;; logical pathnames are upper-case,
-                              ;; at least in the CLHS and on SBCL,
-                              ;; yet (coerce-name :foo) is lower-case.
-                              ;; won't work well with (load-system "Foo")
-                              ;; instead of (load-system 'foo)
-                              (string-downcase name)
-                              name)))
+  (defun parse-source-registry-string (string &key location)
+    (cond
+      ((or (null string) (equal string ""))
+       '(:source-registry :inherit-configuration))
+      ((not (stringp string))
+       (error (compatfmt "~@<Environment string isn't: ~3i~_~S~@:>") string))
+      ((find (char string 0) "\"(")
+       (validate-source-registry-form (read-from-string string) :location location))
+      (t
+       (loop
+         :with inherit = nil
+         :with directives = ()
+         :with start = 0
+         :with end = (length string)
+         :with separator = (inter-directory-separator)
+         :for pos = (position separator string :start start) :do
+           (let ((s (subseq string start (or pos end))))
+             (flet ((check (dir)
+                      (unless (absolute-pathname-p dir)
+                        (error (compatfmt "~@<source-registry string must specify absolute pathnames: ~3i~_~S~@:>") string))
+                      dir))
                (cond
-                 ((gethash name registry) ; already shadowed by something else
-                  nil)
-                 ((gethash name h) ; conflict at current level
-                  (when *asdf-verbose*
-                    (warn (compatfmt "~@<In source-registry entry ~A~@[/~*~] ~
-                                found several entries for ~A - picking ~S over ~S~:>")
-                          directory recurse name (gethash name h) asd)))
+                 ((equal "" s) ; empty element: inherit
+                  (when inherit
+                    (error (compatfmt "~@<Only one inherited configuration allowed: ~3i~_~S~@:>")
+                           string))
+                  (setf inherit t)
+                  (push ':inherit-configuration directives))
+                 ((string-suffix-p s "//") ;; TODO: allow for doubling of separator even outside Unix?
+                  (push `(:tree ,(check (subseq s 0 (- (length s) 2)))) directives))
                  (t
-                  (setf (gethash name registry) asd)
-                  (setf (gethash name h) asd))))))
-        h)))
-  (values))
-
-(defvar *source-registry-parameter* nil)
-
-(defun* initialize-source-registry (&optional (parameter *source-registry-parameter*))
-  ;; Record the parameter used to configure the registry 
-  (setf *source-registry-parameter* parameter)
-  ;; Clear the previous registry database:
-  (setf *source-registry* (make-hash-table :test 'equal))
-  ;; Do it!
-  (compute-source-registry parameter))
-
-;; Checks an initial variable to see whether the state is initialized
-;; or cleared. In the former case, return current configuration; in
-;; the latter, initialize.  ASDF will call this function at the start
-;; of (asdf:find-system) to make sure the source registry is initialized.
-;; However, it will do so *without* a parameter, at which point it
-;; will be too late to provide a parameter to this function, though
-;; you may override the configuration explicitly by calling
-;; initialize-source-registry directly with your parameter.
-(defun* ensure-source-registry (&optional parameter)
-  (unless (source-registry-initialized-p)
-    (initialize-source-registry parameter))
-  (values))
-
-(defun* sysdef-source-registry-search (system)
-  (ensure-source-registry)
-  (values (gethash (primary-system-name system) *source-registry*)))
+                  (push `(:directory ,(check s)) directives))))
+             (cond
+               (pos
+                (setf start (1+ pos)))
+               (t
+                (unless inherit
+                  (push '(:ignore-inherited-configuration) directives))
+                (return `(:source-registry ,@(nreverse directives))))))))))
+
+  (defun register-asd-directory (directory &key recurse exclude collect)
+    (if (not recurse)
+        (collect-asds-in-directory directory collect)
+        (collect-sub*directories-asd-files
+         directory :exclude exclude :collect collect)))
+
+  (defparameter *default-source-registries*
+    '(environment-source-registry
+      user-source-registry
+      user-source-registry-directory
+      system-source-registry
+      system-source-registry-directory
+      default-source-registry))
+
+  (defparameter *source-registry-file* (parse-unix-namestring "source-registry.conf"))
+  (defparameter *source-registry-directory* (parse-unix-namestring "source-registry.conf.d/"))
+
+  (defun wrapping-source-registry ()
+    `(:source-registry
+      #+(or ecl sbcl) (:tree ,(resolve-symlinks* (lisp-implementation-directory)))
+      #+mkcl (:tree ,(translate-logical-pathname "CONTRIB:"))
+      :inherit-configuration
+      #+cmu (:tree #p"modules:")
+      #+scl (:tree #p"file://modules/")))
+  (defun default-source-registry ()
+    `(:source-registry
+      #+sbcl (:directory ,(subpathname (user-homedir-pathname) ".sbcl/systems/"))
+      ,@(loop :for dir :in
+              `(,@(when (os-unix-p)
+                    `(,(or (getenv-absolute-directory "XDG_DATA_HOME")
+                           (subpathname (user-homedir-pathname) ".local/share/"))
+                      ,@(or (getenv-absolute-directories "XDG_DATA_DIRS")
+                            '("/usr/local/share" "/usr/share"))))
+                ,@(when (os-windows-p)
+                    (mapcar 'get-folder-path '(:local-appdata :appdata :common-appdata))))
+              :collect `(:directory ,(subpathname* dir "common-lisp/systems/"))
+              :collect `(:tree ,(subpathname* dir "common-lisp/source/")))
+      :inherit-configuration))
+  (defun user-source-registry (&key (direction :input))
+    (in-user-configuration-directory *source-registry-file* :direction direction))
+  (defun system-source-registry (&key (direction :input))
+    (in-system-configuration-directory *source-registry-file* :direction direction))
+  (defun user-source-registry-directory (&key (direction :input))
+    (in-user-configuration-directory *source-registry-directory* :direction direction))
+  (defun system-source-registry-directory (&key (direction :input))
+    (in-system-configuration-directory *source-registry-directory* :direction direction))
+  (defun environment-source-registry ()
+    (getenv "CL_SOURCE_REGISTRY"))
+
+  (defgeneric* (process-source-registry) (spec &key inherit register))
+
+  (defun* (inherit-source-registry) (inherit &key register)
+    (when inherit
+      (process-source-registry (first inherit) :register register :inherit (rest inherit))))
+
+  (defun* (process-source-registry-directive) (directive &key inherit register)
+    (destructuring-bind (kw &rest rest) (if (consp directive) directive (list directive))
+      (ecase kw
+        ((:include)
+         (destructuring-bind (pathname) rest
+           (process-source-registry (resolve-location pathname) :inherit nil :register register)))
+        ((:directory)
+         (destructuring-bind (pathname) rest
+           (when pathname
+             (funcall register (resolve-location pathname :ensure-directory t)))))
+        ((:tree)
+         (destructuring-bind (pathname) rest
+           (when pathname
+             (funcall register (resolve-location pathname :ensure-directory t)
+                      :recurse t :exclude *source-registry-exclusions*))))
+        ((:exclude)
+         (setf *source-registry-exclusions* rest))
+        ((:also-exclude)
+         (appendf *source-registry-exclusions* rest))
+        ((:default-registry)
+         (inherit-source-registry '(default-source-registry) :register register))
+        ((:inherit-configuration)
+         (inherit-source-registry inherit :register register))
+        ((:ignore-inherited-configuration)
+         nil)))
+    nil)
+
+  (defmethod process-source-registry ((x symbol) &key inherit register)
+    (process-source-registry (funcall x) :inherit inherit :register register))
+  (defmethod process-source-registry ((pathname #-gcl2.6 pathname #+gcl2.6 t) &key inherit register)
+    (cond
+      ((directory-pathname-p pathname)
+       (let ((*here-directory* (resolve-symlinks* pathname)))
+         (process-source-registry (validate-source-registry-directory pathname)
+                                  :inherit inherit :register register)))
+      ((probe-file* pathname :truename *resolve-symlinks*)
+       (let ((*here-directory* (pathname-directory-pathname pathname)))
+         (process-source-registry (validate-source-registry-file pathname)
+                                  :inherit inherit :register register)))
+      (t
+       (inherit-source-registry inherit :register register))))
+  (defmethod process-source-registry ((string string) &key inherit register)
+    (process-source-registry (parse-source-registry-string string)
+                             :inherit inherit :register register))
+  (defmethod process-source-registry ((x null) &key inherit register)
+    (declare (ignorable x))
+    (inherit-source-registry inherit :register register))
+  (defmethod process-source-registry ((form cons) &key inherit register)
+    (let ((*source-registry-exclusions* *default-source-registry-exclusions*))
+      (dolist (directive (cdr (validate-source-registry-form form)))
+        (process-source-registry-directive directive :inherit inherit :register register))))
+
+  (defun flatten-source-registry (&optional parameter)
+    (remove-duplicates
+     (while-collecting (collect)
+       (with-pathname-defaults () ;; be location-independent
+         (inherit-source-registry
+          `(wrapping-source-registry
+            ,parameter
+            ,@*default-source-registries*)
+          :register #'(lambda (directory &key recurse exclude)
+                        (collect (list directory :recurse recurse :exclude exclude))))))
+     :test 'equal :from-end t))
+
+  ;; Will read the configuration and initialize all internal variables.
+  (defun compute-source-registry (&optional parameter (registry *source-registry*))
+    (dolist (entry (flatten-source-registry parameter))
+      (destructuring-bind (directory &key recurse exclude) entry
+        (let* ((h (make-hash-table :test 'equal))) ; table to detect duplicates
+          (register-asd-directory
+           directory :recurse recurse :exclude exclude :collect
+           #'(lambda (asd)
+               (let* ((name (pathname-name asd))
+                      (name (if (typep asd 'logical-pathname)
+                                ;; logical pathnames are upper-case,
+                                ;; at least in the CLHS and on SBCL,
+                                ;; yet (coerce-name :foo) is lower-case.
+                                ;; won't work well with (load-system "Foo")
+                                ;; instead of (load-system 'foo)
+                                (string-downcase name)
+                                name)))
+                 (cond
+                   ((gethash name registry) ; already shadowed by something else
+                    nil)
+                   ((gethash name h) ; conflict at current level
+                    (when *verbose-out*
+                      (warn (compatfmt "~@<In source-registry entry ~A~@[/~*~] ~
+                                found several entries for ~A - picking ~S over ~S~:>")
+                            directory recurse name (gethash name h) asd)))
+                   (t
+                    (setf (gethash name registry) asd)
+                    (setf (gethash name h) asd))))))
+          h)))
+    (values))
+
+  (defvar *source-registry-parameter* nil)
+
+  (defun initialize-source-registry (&optional (parameter *source-registry-parameter*))
+    ;; Record the parameter used to configure the registry 
+    (setf *source-registry-parameter* parameter)
+    ;; Clear the previous registry database:
+    (setf *source-registry* (make-hash-table :test 'equal))
+    ;; Do it!
+    (compute-source-registry parameter))
+
+  ;; Checks an initial variable to see whether the state is initialized
+  ;; or cleared. In the former case, return current configuration; in
+  ;; the latter, initialize.  ASDF will call this function at the start
+  ;; of (asdf:find-system) to make sure the source registry is initialized.
+  ;; However, it will do so *without* a parameter, at which point it
+  ;; will be too late to provide a parameter to this function, though
+  ;; you may override the configuration explicitly by calling
+  ;; initialize-source-registry directly with your parameter.
+  (defun ensure-source-registry (&optional parameter)
+    (unless (source-registry-initialized-p)
+      (initialize-source-registry parameter))
+    (values))
+
+  (defun sysdef-source-registry-search (system)
+    (ensure-source-registry)
+    (values (gethash (primary-system-name system) *source-registry*))))
+
+
 ;;;; -------------------------------------------------------------------------
 ;;; Internal hacks for backward-compatibility 
 
@@ -7718,71 +8024,82 @@
 (in-package :asdf/backward-internals)
 
 ;;;; Backward compatibility with "inline methods"
-
-(defparameter +asdf-methods+
-  '(perform-with-restarts perform explain output-files operation-done-p))
-
-(defun* %remove-component-inline-methods (component)
-  (dolist (name +asdf-methods+)
-    (map ()
-         ;; this is inefficient as most of the stored
-         ;; methods will not be for this particular gf
-         ;; But this is hardly performance-critical
-         #'(lambda (m)
-             (remove-method (symbol-function name) m))
-         (component-inline-methods component)))
-  ;; clear methods, then add the new ones
-  (component-inline-methods component) nil)
-
-(defun* %define-component-inline-methods (ret rest)
-  (dolist (name +asdf-methods+)
-    (let ((keyword (intern (symbol-name name) :keyword)))
-      (loop :for data = rest :then (cddr data)
-        :for key = (first data)
-        :for value = (second data)
-        :while data
-        :when (eq key keyword) :do
-        (destructuring-bind (op qual (o c) &body body) value
-          (pushnew
-           (eval `(defmethod ,name ,qual ((,o ,op) (,c (eql ,ret)))
-                             , at body))
-           (component-inline-methods ret)))))))
-
-(defun* %refresh-component-inline-methods (component rest)
-  (%remove-component-inline-methods component)
-  (%define-component-inline-methods component rest))
+(with-upgradability ()
+  (defparameter +asdf-methods+
+    '(perform-with-restarts perform explain output-files operation-done-p))
+
+  (defun %remove-component-inline-methods (component)
+    (dolist (name +asdf-methods+)
+      (map ()
+           ;; this is inefficient as most of the stored
+           ;; methods will not be for this particular gf
+           ;; But this is hardly performance-critical
+           #'(lambda (m)
+               (remove-method (symbol-function name) m))
+           (component-inline-methods component)))
+    (component-inline-methods component) nil)
+
+  (defun %define-component-inline-methods (ret rest)
+    (dolist (name +asdf-methods+)
+      (let ((keyword (intern (symbol-name name) :keyword)))
+        (loop :for data = rest :then (cddr data)
+              :for key = (first data)
+              :for value = (second data)
+              :while data
+              :when (eq key keyword) :do
+                (destructuring-bind (op qual? &rest rest) value
+                  (multiple-value-bind (qual args-and-body)
+                      (if (symbolp qual?)
+                          (values (list qual?) rest)
+                          (values nil (cons qual? rest)))
+                    (destructuring-bind ((o c) &body body) args-and-body
+                      (pushnew
+                       (eval `(defmethod ,name , at qual ((,o ,op) (,c (eql ,ret)))
+                                , at body))
+                       (component-inline-methods ret)))))))))
+
+  (defun %refresh-component-inline-methods (component rest)
+    ;; clear methods, then add the new ones
+    (%remove-component-inline-methods component)
+    (%define-component-inline-methods component rest)))
 
 ;;;; PARTIAL SUPPORT for the :if-component-dep-fails component attribute
 ;; and the companion asdf:feature pseudo-dependency.
 ;; This won't recurse into dependencies to accumulate feature conditions.
 ;; Therefore it will accept the SB-ROTATE-BYTE of an old SBCL
 ;; (older than 1.1.2.20-fe6da9f) but won't suffice to load an old nibbles.
-(defun* %resolve-if-component-dep-fails (if-component-dep-fails component)
-  (asdf-message "The system definition for ~S uses deprecated ~
+(with-upgradability ()
+  (defun %resolve-if-component-dep-fails (if-component-dep-fails component)
+    (asdf-message "The system definition for ~S uses deprecated ~
                  ASDF option :IF-COMPONENT-DEP-DAILS. ~
                  Starting with ASDF 3, please use :IF-FEATURE instead"
-                (coerce-name (component-system component)))
-  ;; This only supports the pattern of use of the "feature" seen in the wild
-  (check-type component parent-component)
-  (check-type if-component-dep-fails (member :fail :ignore :try-next))
-  (unless (eq if-component-dep-fails :fail)
-    (loop :with o = (make-operation 'compile-op)
-      :for c :in (component-children component) :do
-        (loop* :for (feature? feature) :in (component-depends-on o c)
-               :when (eq feature? 'feature) :do
-                 (setf (component-if-feature c) feature)))))
+                  (coerce-name (component-system component)))
+    ;; This only supports the pattern of use of the "feature" seen in the wild
+    (check-type component parent-component)
+    (check-type if-component-dep-fails (member :fail :ignore :try-next))
+    (unless (eq if-component-dep-fails :fail)
+      (loop :with o = (make-operation 'compile-op)
+            :for c :in (component-children component) :do
+              (loop* :for (feature? feature) :in (component-depends-on o c)
+                     :when (eq feature? 'feature) :do
+                     (setf (component-if-feature c) feature))))))
 
-(when-upgrade (:when (fboundp 'make-sub-operation))
-  (defun* make-sub-operation (c o dep-c dep-o)
+(when-upgrading (:when (fboundp 'make-sub-operation))
+  (defun make-sub-operation (c o dep-c dep-o)
     (declare (ignore c o dep-c dep-o)) (asdf-upgrade-error)))
 
 
 ;;;; load-sysdef
-(defun* load-sysdef (name pathname)
-  (load-asd pathname :name name))
-
-(defun* make-temporary-package ()
-  (make-package (fresh-package-name :prefix :asdf :index 0) :use '(:cl :asdf/interface)))
+(with-upgradability ()
+  (defun load-sysdef (name pathname)
+    (load-asd pathname :name name))
+
+  (defun make-temporary-package ()
+    ;; For loading a .asd file, we dont't make a temporary package anymore,
+    ;; but use ASDF-USER. I'd like to have this function do this,
+    ;; but since whoever uses it is likely to delete-package the result afterwards,
+    ;; this would be a bad idea, so preserve the old behavior.
+    (make-package (fresh-package-name :prefix :asdf :index 0) :use '(:cl :asdf))))
 
 
 ;;;; -------------------------------------------------------------------------
@@ -7802,188 +8119,197 @@
 (in-package :asdf/defsystem)
 
 ;;; Pathname
-
-(defun* determine-system-directory (pathname)
-  ;; The defsystem macro calls this function to determine
-  ;; the pathname of a system as follows:
-  ;; 1. if the pathname argument is an pathname object (NOT a namestring),
-  ;;    that is already an absolute pathname, return it.
-  ;; 2. otherwise, the directory containing the LOAD-PATHNAME
-  ;;    is considered (as deduced from e.g. *LOAD-PATHNAME*), and
-  ;;    if it is indeed available and an absolute pathname, then
-  ;;    the PATHNAME argument is normalized to a relative pathname
-  ;;    as per PARSE-UNIX-NAMESTRING (with ENSURE-DIRECTORY T)
-  ;;    and merged into that DIRECTORY as per SUBPATHNAME.
-  ;;    Note: avoid *COMPILE-FILE-PATHNAME* because .asd is loaded,
-  ;;    and may be from within the EVAL-WHEN of a file compilation.
-  ;; If no absolute pathname was found, we return NIL.
-  (check-type pathname (or null string pathname))
-  (resolve-symlinks*
-   (ensure-pathname-absolute
-    (parse-unix-namestring pathname :type :directory)
-    #'(lambda () (ensure-pathname-absolute
-                  (load-pathname) 'get-pathname-defaults nil))
-    nil)))
+(with-upgradability ()
+  (defun determine-system-directory (pathname)
+    ;; The defsystem macro calls this function to determine
+    ;; the pathname of a system as follows:
+    ;; 1. if the pathname argument is an pathname object (NOT a namestring),
+    ;;    that is already an absolute pathname, return it.
+    ;; 2. otherwise, the directory containing the LOAD-PATHNAME
+    ;;    is considered (as deduced from e.g. *LOAD-PATHNAME*), and
+    ;;    if it is indeed available and an absolute pathname, then
+    ;;    the PATHNAME argument is normalized to a relative pathname
+    ;;    as per PARSE-UNIX-NAMESTRING (with ENSURE-DIRECTORY T)
+    ;;    and merged into that DIRECTORY as per SUBPATHNAME.
+    ;;    Note: avoid *COMPILE-FILE-PATHNAME* because .asd is loaded,
+    ;;    and may be from within the EVAL-WHEN of a file compilation.
+    ;; If no absolute pathname was found, we return NIL.
+    (check-type pathname (or null string pathname))
+    (pathname-directory-pathname
+     (resolve-symlinks*
+      (ensure-absolute-pathname
+       (parse-unix-namestring pathname :type :directory)
+       #'(lambda () (ensure-absolute-pathname
+                     (load-pathname) 'get-pathname-defaults nil))
+       nil)))))
 
 
 ;;; Component class
+(with-upgradability ()
+  (defvar *default-component-class* 'cl-source-file)
 
-(defvar *default-component-class* 'cl-source-file)
-
-(defun* class-for-type (parent type)
-  (or (loop :for symbol :in (list
-                             type
-                             (find-symbol* type *package* nil)
-                             (find-symbol* type :asdf/interface nil))
-        :for class = (and symbol (find-class* symbol nil))
-        :when (and class
-                   (#-cormanlisp subtypep #+cormanlisp cl::subclassp
-                                 class (find-class* 'component)))
-        :return class)
-      (and (eq type :file)
-           (find-class*
-            (or (loop :for p = parent :then (component-parent p) :while p
-                      :thereis (module-default-component-class p))
-                *default-component-class*) nil))
-      (sysdef-error "don't recognize component type ~A" type)))
+  (defun class-for-type (parent type)
+    (or (loop :for symbol :in (list
+                               type
+                               (find-symbol* type *package* nil)
+                               (find-symbol* type :asdf/interface nil))
+              :for class = (and symbol (find-class* symbol nil))
+              :when (and class
+                         (#-cormanlisp subtypep #+cormanlisp cl::subclassp
+                          class (find-class* 'component)))
+                :return class)
+        (and (eq type :file)
+             (find-class*
+              (or (loop :for p = parent :then (component-parent p) :while p
+                        :thereis (module-default-component-class p))
+                  *default-component-class*) nil))
+        (sysdef-error "don't recognize component type ~A" type))))
 
 
 ;;; Check inputs
-
-(define-condition duplicate-names (system-definition-error)
-  ((name :initarg :name :reader duplicate-names-name))
-  (:report (lambda (c s)
-             (format s (compatfmt "~@<Error while defining system: multiple components are given same name ~A~@:>")
-                     (duplicate-names-name c)))))
-
-(defun* sysdef-error-component (msg type name value)
-  (sysdef-error (strcat msg (compatfmt "~&~@<The value specified for ~(~A~) ~A is ~S~@:>"))
-                type name value))
-
-(defun* check-component-input (type name weakly-depends-on
-                                    depends-on components)
-  "A partial test of the values of a component."
-  (unless (listp depends-on)
-    (sysdef-error-component ":depends-on must be a list."
-                            type name depends-on))
-  (unless (listp weakly-depends-on)
-    (sysdef-error-component ":weakly-depends-on must be a list."
-                            type name weakly-depends-on))
-  (unless (listp components)
-    (sysdef-error-component ":components must be NIL or a list of components."
-                            type name components)))
-
-(defun* normalize-version (form pathname)
-  (etypecase form
-    ((or string null) form)
-    (cons
-     (ecase (first form)
-       ((:read-file-form)
-        (destructuring-bind (subpath &key (at 0)) (rest form)
-          (safe-read-file-form (subpathname pathname subpath) :at at)))))))
+(with-upgradability ()
+  (define-condition duplicate-names (system-definition-error)
+    ((name :initarg :name :reader duplicate-names-name))
+    (:report (lambda (c s)
+               (format s (compatfmt "~@<Error while defining system: multiple components are given same name ~A~@:>")
+                       (duplicate-names-name c)))))
+
+  (defun sysdef-error-component (msg type name value)
+    (sysdef-error (strcat msg (compatfmt "~&~@<The value specified for ~(~A~) ~A is ~S~@:>"))
+                  type name value))
+
+  (defun check-component-input (type name weakly-depends-on
+                                depends-on components)
+    "A partial test of the values of a component."
+    (unless (listp depends-on)
+      (sysdef-error-component ":depends-on must be a list."
+                              type name depends-on))
+    (unless (listp weakly-depends-on)
+      (sysdef-error-component ":weakly-depends-on must be a list."
+                              type name weakly-depends-on))
+    (unless (listp components)
+      (sysdef-error-component ":components must be NIL or a list of components."
+                              type name components)))
+
+  (defun normalize-version (form pathname)
+    (etypecase form
+      ((or string null) form)
+      (real
+       (asdf-message "Invalid use of real number ~D as :version in ~S. Substituting a string."
+                     form pathname)
+       (format nil "~D" form)) ;; 1.0 is "1.0"
+      (cons
+       (ecase (first form)
+         ((:read-file-form)
+          (destructuring-bind (subpath &key (at 0)) (rest form)
+            (safe-read-file-form (subpathname pathname subpath) :at at))))))))
 
 
 ;;; Main parsing function
+(with-upgradability ()
+  (defun* (parse-component-form) (parent options &key previous-serial-component)
+    (destructuring-bind
+        (type name &rest rest &key
+                                (builtin-system-p () bspp)
+                                ;; the following list of keywords is reproduced below in the
+                                ;; remove-plist-keys form.  important to keep them in sync
+                                components pathname perform explain output-files operation-done-p
+                                weakly-depends-on depends-on serial
+                                do-first if-component-dep-fails (version nil versionp)
+                                ;; list ends
+         &allow-other-keys) options
+      (declare (ignorable perform explain output-files operation-done-p builtin-system-p))
+      (check-component-input type name weakly-depends-on depends-on components)
+      (when (and parent
+                 (find-component parent name)
+                 (not ;; ignore the same object when rereading the defsystem
+                  (typep (find-component parent name)
+                         (class-for-type parent type))))
+        (error 'duplicate-names :name name))
+      (when do-first (error "DO-FIRST is not supported anymore as of ASDF 3"))
+      (let* ((args `(:name ,(coerce-name name)
+                     :pathname ,pathname
+                     ,@(when parent `(:parent ,parent))
+                     ,@(remove-plist-keys
+                        '(:components :pathname :if-component-dep-fails :version
+                          :perform :explain :output-files :operation-done-p
+                          :weakly-depends-on :depends-on :serial)
+                        rest)))
+             (component (find-component parent name)))
+        (when weakly-depends-on
+          ;; ASDF4: deprecate this feature and remove it.
+          (appendf depends-on
+                   (remove-if (complement #'(lambda (x) (find-system x nil))) weakly-depends-on)))
+        (when previous-serial-component
+          (push previous-serial-component depends-on))
+        (if component ; preserve identity
+            (apply 'reinitialize-instance component args)
+            (setf component (apply 'make-instance (class-for-type parent type) args)))
+        (component-pathname component) ; eagerly compute the absolute pathname
+        (let ((sysdir (system-source-directory (component-system component)))) ;; requires the previous
+          (when (and (typep component 'system) (not bspp))
+            (setf (builtin-system-p component) (lisp-implementation-pathname-p sysdir)))
+          (setf version (normalize-version version sysdir)))
+        (when (and versionp version (not (parse-version version nil)))
+          (warn (compatfmt "~@<Invalid version ~S for component ~S~@[ of ~S~]~@:>")
+                version name parent))
+        ;; Don't use the accessor: kluge to avoid upgrade issue on CCL 1.8.
+        ;; A better fix is required.
+        (setf (slot-value component 'version) version)
+        (when (typep component 'parent-component)
+          (setf (component-children component)
+                (loop
+                  :with previous-component = nil
+                  :for c-form :in components
+                  :for c = (parse-component-form component c-form
+                                                 :previous-serial-component previous-component)
+                  :for name = (component-name c)
+                  :collect c
+                  :when serial :do (setf previous-component name)))
+          (compute-children-by-name component))
+        ;; Used by POIU. ASDF4: rename to component-depends-on?
+        (setf (component-sibling-dependencies component) depends-on)
+        (%refresh-component-inline-methods component rest)
+        (when if-component-dep-fails
+          (%resolve-if-component-dep-fails if-component-dep-fails component))
+        component)))
+
+  (defun register-system-definition
+      (name &rest options &key pathname (class 'system) (source-file () sfp)
+                            defsystem-depends-on &allow-other-keys)
+    ;; The system must be registered before we parse the body,
+    ;; otherwise we recur when trying to find an existing system
+    ;; of the same name to reuse options (e.g. pathname) from.
+    ;; To avoid infinite recursion in cases where you defsystem a system
+    ;; that is registered to a different location to find-system,
+    ;; we also need to remember it in a special variable *systems-being-defined*.
+    (with-system-definitions ()
+      (let* ((name (coerce-name name))
+             (source-file (if sfp source-file (resolve-symlinks* (load-pathname))))
+             (registered (system-registered-p name))
+             (registered! (if registered
+                              (rplaca registered (get-file-stamp source-file))
+                              (register-system
+                               (make-instance 'system :name name :source-file source-file))))
+             (system (reset-system (cdr registered!)
+                                   :name name :source-file source-file))
+             (component-options (remove-plist-key :class options))
+             (defsystem-dependencies (loop :for spec :in defsystem-depends-on :collect
+                                           (resolve-dependency-spec nil spec))))
+        (apply 'load-systems defsystem-dependencies)
+        ;; We change-class AFTER we loaded the defsystem-depends-on
+        ;; since the class might be defined as part of those.
+        (let ((class (class-for-type nil class)))
+          (unless (eq (type-of system) class)
+            (change-class system class)))
+        (parse-component-form
+         nil (list*
+              :module name
+              :pathname (determine-system-directory pathname)
+              component-options)))))
 
-(defun* parse-component-form (parent options &key previous-serial-component)
-  (destructuring-bind
-      (type name &rest rest &key
-       (builtin-system-p () bspp)
-       ;; the following list of keywords is reproduced below in the
-       ;; remove-plist-keys form.  important to keep them in sync
-       components pathname perform explain output-files operation-done-p
-       weakly-depends-on depends-on serial
-       do-first if-component-dep-fails (version nil versionp)
-       ;; list ends
-       &allow-other-keys) options
-    (declare (ignorable perform explain output-files operation-done-p builtin-system-p))
-    (check-component-input type name weakly-depends-on depends-on components)
-    (when (and parent
-               (find-component parent name)
-               (not ;; ignore the same object when rereading the defsystem
-                (typep (find-component parent name)
-                       (class-for-type parent type))))
-      (error 'duplicate-names :name name))
-    (when do-first (error "DO-FIRST is not supported anymore as of ASDF 3"))
-    (let* ((args `(:name ,(coerce-name name)
-                   :pathname ,pathname
-                   ,@(when parent `(:parent ,parent))
-                   ,@(remove-plist-keys
-                      '(:components :pathname :if-component-dep-fails :version
-                        :perform :explain :output-files :operation-done-p
-                        :weakly-depends-on :depends-on :serial)
-                      rest)))
-           (component (find-component parent name)))
-      (when weakly-depends-on
-        ;; ASDF4: deprecate this feature and remove it.
-        (appendf depends-on
-                 (remove-if (complement #'(lambda (x) (find-system x nil))) weakly-depends-on)))
-      (when previous-serial-component
-        (push previous-serial-component depends-on))
-      (if component ; preserve identity
-          (apply 'reinitialize-instance component args)
-          (setf component (apply 'make-instance (class-for-type parent type) args)))
-      (component-pathname component) ; eagerly compute the absolute pathname
-      (let ((sysdir (system-source-directory (component-system component)))) ;; requires the previous
-        (when (and (typep component 'system) (not bspp))
-          (setf (builtin-system-p component) (lisp-implementation-pathname-p sysdir)))
-        (setf version (normalize-version version sysdir)))
-      (when (and versionp version (not (parse-version version nil)))
-        (warn (compatfmt "~@<Invalid version ~S for component ~S~@[ of ~S~]~@:>")
-              version name parent))
-      (setf (component-version component) version)
-      (when (typep component 'parent-component)
-        (setf (component-children component)
-              (loop
-                :with previous-component = nil
-                :for c-form :in components
-                :for c = (parse-component-form component c-form
-                                               :previous-serial-component previous-component)
-                :for name = (component-name c)
-                :collect c
-                :when serial :do (setf previous-component name)))
-        (compute-children-by-name component))
-      ;; Used by POIU. ASDF4: rename to component-depends-on?
-      (setf (component-sibling-dependencies component) depends-on)
-      (%refresh-component-inline-methods component rest)
-      (when if-component-dep-fails
-        (%resolve-if-component-dep-fails if-component-dep-fails component))
-      component)))
-
-(defun* register-system-definition
-    (name &rest options &key pathname (class 'system) (source-file () sfp)
-          defsystem-depends-on &allow-other-keys)
-  ;; The system must be registered before we parse the body,
-  ;; otherwise we recur when trying to find an existing system
-  ;; of the same name to reuse options (e.g. pathname) from.
-  ;; To avoid infinite recursion in cases where you defsystem a system
-  ;; that is registered to a different location to find-system,
-  ;; we also need to remember it in a special variable *systems-being-defined*.
-  (with-system-definitions ()
-    (let* ((name (coerce-name name))
-           (source-file (if sfp source-file (resolve-symlinks* (load-pathname))))
-           (registered (system-registered-p name))
-           (registered! (if registered
-                            (rplaca registered (get-file-stamp source-file))
-                            (register-system
-                             (make-instance 'system :name name :source-file source-file))))
-           (system (reset-system (cdr registered!)
-                                 :name name :source-file source-file))
-           (component-options (remove-plist-key :class options)))
-      (apply 'load-systems defsystem-depends-on)
-      ;; We change-class AFTER we loaded the defsystem-depends-on
-      ;; since the class might be defined as part of those.
-      (let ((class (class-for-type nil class)))
-        (unless (eq (type-of system) class)
-          (change-class system class)))
-      (parse-component-form
-       nil (list*
-            :module name
-            :pathname (determine-system-directory pathname)
-            component-options)))))
-
-(defmacro defsystem (name &body options)
-  `(apply 'register-system-definition ',name ',options))
+  (defmacro defsystem (name &body options)
+    `(apply 'register-system-definition ',name ',options)))
 ;;;; -------------------------------------------------------------------------
 ;;;; ASDF-Bundle
 
@@ -8006,107 +8332,109 @@
    #:build-args #:name-suffix #:prologue-code #:epilogue-code #:static-library))
 (in-package :asdf/bundle)
 
-(defclass bundle-op (operation)
-  ((build-args :initarg :args :initform nil :accessor bundle-op-build-args)
-   (name-suffix :initarg :name-suffix :initform nil)
-   (bundle-type :initform :no-output-file :reader bundle-type)
-   #+ecl (lisp-files :initform nil :accessor bundle-op-lisp-files)
-   #+mkcl (do-fasb :initarg :do-fasb :initform t :reader bundle-op-do-fasb-p)
-   #+mkcl (do-static-library :initarg :do-static-library :initform t :reader bundle-op-do-static-library-p)))
-
-(defclass fasl-op (bundle-op)
-  ;; create a single fasl for the entire library
-  ((bundle-type :initform :fasl)))
-
-(defclass load-fasl-op (basic-load-op)
-  ;; load a single fasl for the entire library
-  ())
-
-(defclass lib-op (bundle-op)
-  ;; On ECL: compile the system and produce linkable .a library for it.
-  ;; On others: just compile the system.
-  ((bundle-type :initform #+(or ecl mkcl) :lib #-(or ecl mkcl) :no-output-file)))
-
-(defclass dll-op (bundle-op)
-  ;; Link together all the dynamic library used by this system into a single one.
-  ((bundle-type :initform :dll)))
-
-(defclass binary-op (bundle-op)
-  ;; On ECL: produce lib and fasl for the system.
-  ;; On "normal" Lisps: produce just the fasl.
-  ())
-
-(defclass monolithic-op (operation) ()) ;; operation on a system and its dependencies
-
-(defclass monolithic-bundle-op (monolithic-op bundle-op)
-  ((prologue-code :accessor monolithic-op-prologue-code)
-   (epilogue-code :accessor monolithic-op-epilogue-code)))
-
-(defclass monolithic-binary-op (binary-op monolithic-bundle-op)
-  ;; On ECL: produce lib and fasl for combined system and dependencies.
-  ;; On "normal" Lisps: produce an image file from system and dependencies.
-  ())
-
-(defclass monolithic-fasl-op (monolithic-bundle-op fasl-op)
-  ;; Create a single fasl for the system and its dependencies.
-  ())
-
-(defclass monolithic-lib-op (monolithic-bundle-op lib-op)
-  ;; ECL: Create a single linkable library for the system and its dependencies.
-  ((bundle-type :initform :lib)))
-
-(defclass monolithic-dll-op (monolithic-bundle-op dll-op)
-  ((bundle-type :initform :dll)))
-
-(defclass program-op (monolithic-bundle-op)
-  ;; All: create an executable file from the system and its dependencies
-  ((bundle-type :initform :program)))
-
-(defun* bundle-pathname-type (bundle-type)
-  (etypecase bundle-type
-    ((eql :no-output-file) nil) ;; should we error out instead?    
-    ((or null string) bundle-type)
-    ((eql :fasl) #-(or ecl mkcl) (compile-file-type) #+(or ecl mkcl) "fasb")
-    #+ecl
-    ((member :binary :dll :lib :static-library :program :object :program)
-     (compile-file-type :type bundle-type))
-    ((eql :binary) "image")
-    ((eql :dll) (cond ((os-unix-p) "so") ((os-windows-p) "dll")))
-    ((member :lib :static-library) (cond ((os-unix-p) "a") ((os-windows-p) "lib")))
-    ((eql :program) (cond ((os-unix-p) nil) ((os-windows-p) "exe")))))
-
-(defun* bundle-output-files (o c)
-  (let ((bundle-type (bundle-type o)))
-    (unless (eq bundle-type :no-output-file) ;; NIL already means something regarding type.
-      (let ((name (or (component-build-pathname c)
-                      (format nil "~A~@[~A~]" (component-name c) (slot-value o 'name-suffix))))
-            (type (bundle-pathname-type bundle-type)))
-        (values (list (subpathname (component-pathname c) name :type type))
-                (eq (type-of o) (component-build-operation c)))))))
-
-(defmethod output-files ((o bundle-op) (c system))
-  (bundle-output-files o c))
-
-#-(or ecl mkcl)
-(progn
-  (defmethod perform ((o program-op) (c system))
-    (let ((output-file (output-file o c)))
-      (setf *image-entry-point* (ensure-function (component-entry-point c)))
-      (dump-image output-file :executable t)))
-
-  (defmethod perform ((o monolithic-binary-op) (c system))
-    (let ((output-file (output-file o c)))
-      (dump-image output-file))))
-
-(defclass compiled-file (file-component)
-  ((type :initform #-(or ecl mkcl) (compile-file-type) #+(or ecl mkcl) "fasb")))
-
-(defclass precompiled-system (system)
-  ((build-pathname :initarg :fasl)))
-
-(defclass prebuilt-system (system)
-  ((build-pathname :initarg :static-library :initarg :lib
-                    :accessor prebuilt-system-static-library)))
+(with-upgradability ()
+  (defclass bundle-op (operation)
+    ((build-args :initarg :args :initform nil :accessor bundle-op-build-args)
+     (name-suffix :initarg :name-suffix :initform nil)
+     (bundle-type :initform :no-output-file :reader bundle-type)
+     #+ecl (lisp-files :initform nil :accessor bundle-op-lisp-files)
+     #+mkcl (do-fasb :initarg :do-fasb :initform t :reader bundle-op-do-fasb-p)
+     #+mkcl (do-static-library :initarg :do-static-library :initform t :reader bundle-op-do-static-library-p)))
+
+  (defclass fasl-op (bundle-op)
+    ;; create a single fasl for the entire library
+    ((bundle-type :initform :fasl)))
+
+  (defclass load-fasl-op (basic-load-op)
+    ;; load a single fasl for the entire library
+    ())
+
+  (defclass lib-op (bundle-op)
+    ;; On ECL: compile the system and produce linkable .a library for it.
+    ;; On others: just compile the system.
+    ((bundle-type :initform #+(or ecl mkcl) :lib #-(or ecl mkcl) :no-output-file)))
+
+  (defclass dll-op (bundle-op)
+    ;; Link together all the dynamic library used by this system into a single one.
+    ((bundle-type :initform :dll)))
+
+  (defclass binary-op (bundle-op)
+    ;; On ECL: produce lib and fasl for the system.
+    ;; On "normal" Lisps: produce just the fasl.
+    ())
+
+  (defclass monolithic-op (operation) ()) ;; operation on a system and its dependencies
+
+  (defclass monolithic-bundle-op (monolithic-op bundle-op)
+    ((prologue-code :accessor monolithic-op-prologue-code)
+     (epilogue-code :accessor monolithic-op-epilogue-code)))
+
+  (defclass monolithic-binary-op (binary-op monolithic-bundle-op)
+    ;; On ECL: produce lib and fasl for combined system and dependencies.
+    ;; On "normal" Lisps: produce an image file from system and dependencies.
+    ())
+
+  (defclass monolithic-fasl-op (monolithic-bundle-op fasl-op)
+    ;; Create a single fasl for the system and its dependencies.
+    ())
+
+  (defclass monolithic-lib-op (monolithic-bundle-op lib-op)
+    ;; ECL: Create a single linkable library for the system and its dependencies.
+    ((bundle-type :initform :lib)))
+
+  (defclass monolithic-dll-op (monolithic-bundle-op dll-op)
+    ((bundle-type :initform :dll)))
+
+  (defclass program-op (monolithic-bundle-op)
+    ;; All: create an executable file from the system and its dependencies
+    ((bundle-type :initform :program)))
+
+  (defun bundle-pathname-type (bundle-type)
+    (etypecase bundle-type
+      ((eql :no-output-file) nil) ;; should we error out instead?    
+      ((or null string) bundle-type)
+      ((eql :fasl) #-(or ecl mkcl) (compile-file-type) #+(or ecl mkcl) "fasb")
+      #+ecl
+      ((member :binary :dll :lib :static-library :program :object :program)
+       (compile-file-type :type bundle-type))
+      ((eql :binary) "image")
+      ((eql :dll) (cond ((os-unix-p) "so") ((os-windows-p) "dll")))
+      ((member :lib :static-library) (cond ((os-unix-p) "a") ((os-windows-p) "lib")))
+      ((eql :program) (cond ((os-unix-p) nil) ((os-windows-p) "exe")))))
+
+  (defun bundle-output-files (o c)
+    (let ((bundle-type (bundle-type o)))
+      (unless (eq bundle-type :no-output-file) ;; NIL already means something regarding type.
+        (let ((name (or (component-build-pathname c)
+                        (format nil "~A~@[~A~]" (component-name c) (slot-value o 'name-suffix))))
+              (type (bundle-pathname-type bundle-type)))
+          (values (list (subpathname (component-pathname c) name :type type))
+                  (eq (type-of o) (component-build-operation c)))))))
+
+  (defmethod output-files ((o bundle-op) (c system))
+    (bundle-output-files o c))
+
+  #-(or ecl mkcl)
+  (progn
+    (defmethod perform ((o program-op) (c system))
+      (let ((output-file (output-file o c)))
+        (setf *image-entry-point* (ensure-function (component-entry-point c)))
+        (dump-image output-file :executable t)))
+
+    (defmethod perform ((o monolithic-binary-op) (c system))
+      (let ((output-file (output-file o c)))
+        (dump-image output-file))))
+
+  (defclass compiled-file (file-component)
+    ((type :initform #-(or ecl mkcl) (compile-file-type) #+(or ecl mkcl) "fasb")))
+
+  (defclass precompiled-system (system)
+    ((build-pathname :initarg :fasl)))
+
+  (defclass prebuilt-system (system)
+    ((build-pathname :initarg :static-library :initarg :lib
+                     :accessor prebuilt-system-static-library))))
+
 
 ;;;
 ;;; BUNDLE-OP
@@ -8116,55 +8444,56 @@
 ;;; a FASL, a statically linked library, a shared library, etc.
 ;;; The different targets are defined by specialization.
 ;;;
+(with-upgradability ()
+  (defun operation-monolithic-p (op)
+    (typep op 'monolithic-op))
+
+  (defmethod initialize-instance :after ((instance bundle-op) &rest initargs
+                                         &key (name-suffix nil name-suffix-p)
+                                         &allow-other-keys)
+    (declare (ignorable initargs name-suffix))
+    (unless name-suffix-p
+      (setf (slot-value instance 'name-suffix)
+            (unless (typep instance 'program-op)
+              (if (operation-monolithic-p instance) ".all-systems" #-ecl ".system"))))
+    (when (typep instance 'monolithic-bundle-op)
+      (destructuring-bind (&rest original-initargs
+                           &key lisp-files prologue-code epilogue-code
+                           &allow-other-keys)
+          (operation-original-initargs instance)
+        (setf (operation-original-initargs instance)
+              (remove-plist-keys '(:lisp-files :epilogue-code :prologue-code) original-initargs)
+              (monolithic-op-prologue-code instance) prologue-code
+              (monolithic-op-epilogue-code instance) epilogue-code)
+        #-ecl (assert (null (or lisp-files epilogue-code prologue-code)))
+        #+ecl (setf (bundle-op-lisp-files instance) lisp-files)))
+    (setf (bundle-op-build-args instance)
+          (remove-plist-keys '(:type :monolithic :name-suffix)
+                             (operation-original-initargs instance))))
+
+  (defmethod bundle-op-build-args :around ((o lib-op))
+    (declare (ignorable o))
+    (let ((args (call-next-method)))
+      (remf args :ld-flags)
+      args))
+
+  (defun bundlable-file-p (pathname)
+    (let ((type (pathname-type pathname)))
+      (declare (ignorable type))
+      (or #+ecl (or (equal type (compile-file-type :type :object))
+                    (equal type (compile-file-type :type :static-library)))
+          #+mkcl (equal type (compile-file-type :fasl-p nil))
+          #+(or allegro clisp clozure cmu lispworks sbcl scl xcl) (equal type (compile-file-type)))))
+
+  (defgeneric* (trivial-system-p) (component))
+
+  (defun user-system-p (s)
+    (and (typep s 'system)
+         (not (builtin-system-p s))
+         (not (trivial-system-p s)))))
 
-(defun* operation-monolithic-p (op)
-  (typep op 'monolithic-op))
-
-(defmethod initialize-instance :after ((instance bundle-op) &rest initargs
-                                       &key (name-suffix nil name-suffix-p)
-                                       &allow-other-keys)
-  (declare (ignorable initargs name-suffix))
-  (unless name-suffix-p
-    (setf (slot-value instance 'name-suffix)
-          (unless (typep instance 'program-op)
-            (if (operation-monolithic-p instance) ".all-systems" #-ecl ".system"))))
-  (when (typep instance 'monolithic-bundle-op)
-    (destructuring-bind (&rest original-initargs
-                         &key lisp-files prologue-code epilogue-code
-                         &allow-other-keys)
-        (operation-original-initargs instance)
-      (setf (operation-original-initargs instance)
-            (remove-plist-keys '(:lisp-files :epilogue-code :prologue-code) original-initargs)
-            (monolithic-op-prologue-code instance) prologue-code
-            (monolithic-op-epilogue-code instance) epilogue-code)
-      #-ecl (assert (null (or lisp-files epilogue-code prologue-code)))
-      #+ecl (setf (bundle-op-lisp-files instance) lisp-files)))
-  (setf (bundle-op-build-args instance)
-        (remove-plist-keys '(:type :monolithic :name-suffix)
-                     (operation-original-initargs instance))))
-
-(defmethod bundle-op-build-args :around ((o lib-op))
-  (declare (ignorable o))
-  (let ((args (call-next-method)))
-    (remf args :ld-flags)
-    args))
-
-(defun* bundlable-file-p (pathname)
-  (let ((type (pathname-type pathname)))
-    (declare (ignorable type))
-    (or #+ecl (or (equal type (compile-file-type :type :object))
-                  (equal type (compile-file-type :type :static-library)))
-        #+mkcl (equal type (compile-file-type :fasl-p nil))
-        #+(or allegro clisp clozure cmu lispworks sbcl scl xcl) (equal type (compile-file-type)))))
-
-(defgeneric* (trivial-system-p) (component))
-
-(defun* user-system-p (s)
-  (and (typep s 'system)
-       (not (builtin-system-p s))
-       (not (trivial-system-p s))))
-
-(deftype user-system () '(and system (satisfies user-system-p)))
+(eval-when (#-lispworks :compile-toplevel :load-toplevel :execute)
+  (deftype user-system () '(and system (satisfies user-system-p))))
 
 ;;;
 ;;; First we handle monolithic bundles.
@@ -8174,131 +8503,131 @@
 ;;;
 ;;; MONOLITHIC SHARED LIBRARIES, PROGRAMS, FASL
 ;;;
-
-(defmethod component-depends-on ((o monolithic-lib-op) (c system))
-  (declare (ignorable o))
-  `((lib-op ,@(required-components c :other-systems t :component-type 'system
-                                     :goal-operation 'load-op
-                                     :keep-operation 'compile-op))))
-
-(defmethod component-depends-on ((o monolithic-fasl-op) (c system))
-  (declare (ignorable o))
-  `((fasl-op ,@(required-components c :other-systems t :component-type 'system
-                                      :goal-operation 'load-fasl-op
-                                      :keep-operation 'fasl-op))))
-
-(defmethod component-depends-on ((o program-op) (c system))
-  (declare (ignorable o))
-  #+(or ecl mkcl) (component-depends-on (make-operation 'monolithic-lib-op) c)
-  #-(or ecl mkcl) `((load-op ,c)))
-
-(defmethod component-depends-on ((o binary-op) (c system))
-  (declare (ignorable o))
-  `((fasl-op ,c)
-    (lib-op ,c)))
-
-(defmethod component-depends-on ((o monolithic-binary-op) (c system))
-  `((,(find-operation o 'monolithic-fasl-op) ,c)
-    (,(find-operation o 'monolithic-lib-op) ,c)))
-
-(defmethod component-depends-on ((o lib-op) (c system))
-  (declare (ignorable o))
-  `((compile-op ,@(required-components c :other-systems nil :component-type '(not system)
-                                         :goal-operation 'load-op
-                                         :keep-operation 'compile-op))))
-
-(defmethod component-depends-on ((o fasl-op) (c system))
-  (declare (ignorable o))
-  #+ecl `((lib-op ,c))
-  #-ecl
-  (component-depends-on (find-operation o 'lib-op) c))
-
-(defmethod component-depends-on ((o dll-op) c)
-  (component-depends-on (find-operation o 'lib-op) c))
-
-(defmethod component-depends-on ((o bundle-op) c)
-  (declare (ignorable o c))
-  nil)
-
-(defmethod component-depends-on :around ((o bundle-op) (c component))
-  (declare (ignorable o c))
-  (if-let (op (and (eq (type-of o) 'bundle-op) (component-build-operation c)))
+(with-upgradability ()
+  (defmethod component-depends-on ((o monolithic-lib-op) (c system))
+    (declare (ignorable o))
+    `((lib-op ,@(required-components c :other-systems t :component-type 'system
+                                       :goal-operation 'load-op
+                                       :keep-operation 'compile-op))))
+
+  (defmethod component-depends-on ((o monolithic-fasl-op) (c system))
+    (declare (ignorable o))
+    `((fasl-op ,@(required-components c :other-systems t :component-type 'system
+                                        :goal-operation 'load-fasl-op
+                                        :keep-operation 'fasl-op))))
+
+  (defmethod component-depends-on ((o program-op) (c system))
+    (declare (ignorable o))
+    #+(or ecl mkcl) (component-depends-on (make-operation 'monolithic-lib-op) c)
+    #-(or ecl mkcl) `((load-op ,c)))
+
+  (defmethod component-depends-on ((o binary-op) (c system))
+    (declare (ignorable o))
+    `((fasl-op ,c)
+      (lib-op ,c)))
+
+  (defmethod component-depends-on ((o monolithic-binary-op) (c system))
+    `((,(find-operation o 'monolithic-fasl-op) ,c)
+      (,(find-operation o 'monolithic-lib-op) ,c)))
+
+  (defmethod component-depends-on ((o lib-op) (c system))
+    (declare (ignorable o))
+    `((compile-op ,@(required-components c :other-systems nil :component-type '(not system)
+                                           :goal-operation 'load-op
+                                           :keep-operation 'compile-op))))
+
+  (defmethod component-depends-on ((o fasl-op) (c system))
+    (declare (ignorable o))
+    #+ecl `((lib-op ,c))
+    #-ecl
+    (component-depends-on (find-operation o 'lib-op) c))
+
+  (defmethod component-depends-on ((o dll-op) c)
+    (component-depends-on (find-operation o 'lib-op) c))
+
+  (defmethod component-depends-on ((o bundle-op) c)
+    (declare (ignorable o c))
+    nil)
+
+  (defmethod component-depends-on :around ((o bundle-op) (c component))
+    (declare (ignorable o c))
+    (if-let (op (and (eq (type-of o) 'bundle-op) (component-build-operation c)))
       `((,op ,c))
       (call-next-method)))
 
-(defun* direct-dependency-files (o c &key (test 'identity) (key 'output-files) &allow-other-keys)
-  (while-collecting (collect)
-    (map-direct-dependencies
-     o c #'(lambda (sub-o sub-c)
-             (loop :for f :in (funcall key sub-o sub-c)
-                   :when (funcall test f) :do (collect f))))))
-
-(defmethod input-files ((o bundle-op) (c system))
-  (direct-dependency-files o c :test 'bundlable-file-p :key 'output-files))
-
-(defun* select-bundle-operation (type &optional monolithic)
-  (ecase type
-    ((:binary)
-     (if monolithic 'monolithic-binary-op 'binary-op))
-    ((:dll :shared-library)
-     (if monolithic 'monolithic-dll-op 'dll-op))
-    ((:lib :static-library)
-     (if monolithic 'monolithic-lib-op 'lib-op))
-    ((:fasl)
-     (if monolithic 'monolithic-fasl-op 'fasl-op))
-    ((:program)
-     'program-op)))
-
-(defun* make-build (system &rest args &key (monolithic nil) (type :fasl)
-                   (move-here nil move-here-p)
-                   &allow-other-keys)
-  (let* ((operation-name (select-bundle-operation type monolithic))
-         (move-here-path (if (and move-here
-                                  (typep move-here '(or pathname string)))
-                             (pathname move-here)
-                             (merge-pathnames "./asdf-output/")))
-         (operation (apply #'operate operation-name
-                           system
-                           (remove-plist-keys '(:monolithic :type :move-here) args)))
-         (system (find-system system))
-         (files (and system (output-files operation system))))
-    (if (or move-here (and (null move-here-p)
-                           (member operation-name '(:program :binary))))
-        (loop :with dest-path = (resolve-symlinks* (ensure-directories-exist move-here-path))
-              :for f :in files
-              :for new-f = (make-pathname :name (pathname-name f)
-                                :type (pathname-type f)
-                                :defaults dest-path)
-              :do (rename-file-overwriting-target f new-f)
-              :collect new-f)
-        files)))
+  (defun direct-dependency-files (o c &key (test 'identity) (key 'output-files) &allow-other-keys)
+    (while-collecting (collect)
+      (map-direct-dependencies
+       o c #'(lambda (sub-o sub-c)
+               (loop :for f :in (funcall key sub-o sub-c)
+                     :when (funcall test f) :do (collect f))))))
+
+  (defmethod input-files ((o bundle-op) (c system))
+    (direct-dependency-files o c :test 'bundlable-file-p :key 'output-files))
+
+  (defun select-bundle-operation (type &optional monolithic)
+    (ecase type
+      ((:binary)
+       (if monolithic 'monolithic-binary-op 'binary-op))
+      ((:dll :shared-library)
+       (if monolithic 'monolithic-dll-op 'dll-op))
+      ((:lib :static-library)
+       (if monolithic 'monolithic-lib-op 'lib-op))
+      ((:fasl)
+       (if monolithic 'monolithic-fasl-op 'fasl-op))
+      ((:program)
+       'program-op)))
+
+  (defun make-build (system &rest args &key (monolithic nil) (type :fasl)
+                             (move-here nil move-here-p)
+                             &allow-other-keys)
+    (let* ((operation-name (select-bundle-operation type monolithic))
+           (move-here-path (if (and move-here
+                                    (typep move-here '(or pathname string)))
+                               (pathname move-here)
+                               (system-relative-pathname system "asdf-output/")))
+           (operation (apply #'operate operation-name
+                             system
+                             (remove-plist-keys '(:monolithic :type :move-here) args)))
+           (system (find-system system))
+           (files (and system (output-files operation system))))
+      (if (or move-here (and (null move-here-p)
+                             (member operation-name '(:program :binary))))
+          (loop :with dest-path = (resolve-symlinks* (ensure-directories-exist move-here-path))
+                :for f :in files
+                :for new-f = (make-pathname :name (pathname-name f)
+                                            :type (pathname-type f)
+                                            :defaults dest-path)
+                :do (rename-file-overwriting-target f new-f)
+                :collect new-f)
+          files))))
 
 ;;;
 ;;; LOAD-FASL-OP
 ;;;
 ;;; This is like ASDF's LOAD-OP, but using monolithic fasl files.
 ;;;
+(with-upgradability ()
+  (defmethod component-depends-on ((o load-fasl-op) (c system))
+    (declare (ignorable o))
+    `((,o ,@(loop :for dep :in (component-sibling-dependencies c)
+                  :collect (resolve-dependency-spec c dep)))
+      (,(if (user-system-p c) 'fasl-op 'load-op) ,c)
+      ,@(call-next-method)))
+
+  (defmethod input-files ((o load-fasl-op) (c system))
+    (when (user-system-p c)
+      (output-files (find-operation o 'fasl-op) c)))
+
+  (defmethod perform ((o load-fasl-op) c)
+    (declare (ignorable o c))
+    nil)
 
-(defmethod component-depends-on ((o load-fasl-op) (c system))
-  (declare (ignorable o))
-  `((,o ,@(loop :for dep :in (component-sibling-dependencies c)
-                :collect (resolve-dependency-spec c dep)))
-    (,(if (user-system-p c) 'fasl-op 'load-op) ,c)
-    ,@(call-next-method)))
-
-(defmethod input-files ((o load-fasl-op) (c system))
-  (when (user-system-p c)
-    (output-files (find-operation o 'fasl-op) c)))
-
-(defmethod perform ((o load-fasl-op) c)
-  (declare (ignorable o c))
-  nil)
-
-(defmethod perform ((o load-fasl-op) (c system))
-  (perform-lisp-load-fasl o c))
+  (defmethod perform ((o load-fasl-op) (c system))
+    (perform-lisp-load-fasl o c))
 
-(defmethod mark-operation-done :after ((o load-fasl-op) (c system))
-  (mark-operation-done (find-operation o 'load-op) c))
+  (defmethod mark-operation-done :after ((o load-fasl-op) (c system))
+    (mark-operation-done (find-operation o 'load-op) c)))
 
 ;;;
 ;;; PRECOMPILED FILES
@@ -8306,131 +8635,132 @@
 ;;; This component can be used to distribute ASDF systems in precompiled form.
 ;;; Only useful when the dependencies have also been precompiled.
 ;;;
-
-(defmethod trivial-system-p ((s system))
-  (every #'(lambda (c) (typep c 'compiled-file)) (component-children s)))
-
-(defmethod output-files (o (c compiled-file))
-  (declare (ignorable o c))
-  nil)
-(defmethod input-files (o (c compiled-file))
-  (declare (ignorable o))
-  (component-pathname c))
-(defmethod perform ((o load-op) (c compiled-file))
-  (perform-lisp-load-fasl o c))
-(defmethod perform ((o load-source-op) (c compiled-file))
-  (perform (find-operation o 'load-op) c))
-(defmethod perform ((o load-fasl-op) (c compiled-file))
-  (perform (find-operation o 'load-op) c))
-(defmethod perform (o (c compiled-file))
-  (declare (ignorable o c))
-  nil)
+(with-upgradability ()
+  (defmethod trivial-system-p ((s system))
+    (every #'(lambda (c) (typep c 'compiled-file)) (component-children s)))
+
+  (defmethod output-files (o (c compiled-file))
+    (declare (ignorable o c))
+    nil)
+  (defmethod input-files (o (c compiled-file))
+    (declare (ignorable o))
+    (component-pathname c))
+  (defmethod perform ((o load-op) (c compiled-file))
+    (perform-lisp-load-fasl o c))
+  (defmethod perform ((o load-source-op) (c compiled-file))
+    (perform (find-operation o 'load-op) c))
+  (defmethod perform ((o load-fasl-op) (c compiled-file))
+    (perform (find-operation o 'load-op) c))
+  (defmethod perform (o (c compiled-file))
+    (declare (ignorable o c))
+    nil))
 
 ;;;
 ;;; Pre-built systems
 ;;;
-(defmethod trivial-system-p ((s prebuilt-system))
-  (declare (ignorable s))
-  t)
-
-(defmethod perform ((o lib-op) (c prebuilt-system))
-  (declare (ignorable o c))
-  nil)
-
-(defmethod component-depends-on ((o lib-op) (c prebuilt-system))
-  (declare (ignorable o c))
-  nil)
-
-(defmethod component-depends-on ((o monolithic-lib-op) (c prebuilt-system))
-  (declare (ignorable o))
-  nil)
+(with-upgradability ()
+  (defmethod trivial-system-p ((s prebuilt-system))
+    (declare (ignorable s))
+    t)
+
+  (defmethod perform ((o lib-op) (c prebuilt-system))
+    (declare (ignorable o c))
+    nil)
+
+  (defmethod component-depends-on ((o lib-op) (c prebuilt-system))
+    (declare (ignorable o c))
+    nil)
+
+  (defmethod component-depends-on ((o monolithic-lib-op) (c prebuilt-system))
+    (declare (ignorable o))
+    nil))
 
 
 ;;;
 ;;; PREBUILT SYSTEM CREATOR
 ;;;
-
-
-(defmethod output-files ((o binary-op) (s system))
-  (list (make-pathname :name (component-name s) :type "asd"
-                       :defaults (component-pathname s))))
-
-(defmethod perform ((o binary-op) (s system))
-  (let* ((dependencies (component-depends-on o s))
-         (fasl (first (apply #'output-files (first dependencies))))
-         (library (first (apply #'output-files (second dependencies))))
-         (asd (first (output-files o s)))
-         (name (pathname-name asd))
-         (name-keyword (intern (string name) (find-package :keyword))))
-    (with-open-file (s asd :direction :output :if-exists :supersede
-                       :if-does-not-exist :create)
-      (format s ";;; Prebuilt ASDF definition for system ~A" name)
-      (format s ";;; Built for ~A ~A on a ~A/~A ~A"
-              (lisp-implementation-type)
-              (lisp-implementation-version)
-              (software-type)
-              (machine-type)
-              (software-version))
-      (let ((*package* (find-package :keyword)))
-        (pprint `(defsystem ,name-keyword
+(with-upgradability ()
+  (defmethod output-files ((o binary-op) (s system))
+    (list (make-pathname :name (component-name s) :type "asd"
+                         :defaults (component-pathname s))))
+
+  (defmethod perform ((o binary-op) (s system))
+    (let* ((dependencies (component-depends-on o s))
+           (fasl (first (apply #'output-files (first dependencies))))
+           (library (first (apply #'output-files (second dependencies))))
+           (asd (first (output-files o s)))
+           (name (pathname-name asd))
+           (name-keyword (intern (string name) (find-package :keyword))))
+      (with-open-file (s asd :direction :output :if-exists :supersede
+                             :if-does-not-exist :create)
+        (format s ";;; Prebuilt ASDF definition for system ~A" name)
+        (format s ";;; Built for ~A ~A on a ~A/~A ~A"
+                (lisp-implementation-type)
+                (lisp-implementation-version)
+                (software-type)
+                (machine-type)
+                (software-version))
+        (let ((*package* (find-package :keyword)))
+          (pprint `(defsystem ,name-keyword
                      :class prebuilt-system
                      :components ((:compiled-file ,(pathname-name fasl)))
                      :lib ,(and library (file-namestring library)))
-                s)))))
+                  s)))))
 
-#-(or ecl mkcl)
-(defmethod perform ((o fasl-op) (c system))
-  (let* ((input-files (input-files o c))
-         (fasl-files (remove (compile-file-type) input-files :key #'pathname-type :test-not #'string=))
-         (non-fasl-files (remove (compile-file-type) input-files :key #'pathname-type :test #'string=))
-         (output-files (output-files o c))
-         (output-file (first output-files)))
-    (unless input-files (format t "WTF no input-files for ~S on ~S !???" o c))
-    (when input-files
-      (assert output-files)
-      (when non-fasl-files
-        (error "On ~A, asdf-bundle can only bundle FASL files, but these were also produced: ~S"
-               (implementation-type) non-fasl-files))
-      (when (and (typep o 'monolithic-bundle-op)
-                 (or (monolithic-op-prologue-code o) (monolithic-op-epilogue-code o)))
-        (error "prologue-code and epilogue-code are not supported on ~A"
-               (implementation-type)))
-      (with-staging-pathname (output-file)
-        (combine-fasls fasl-files output-file)))))
-
-(defmethod input-files ((o load-op) (s precompiled-system))
-  (declare (ignorable o))
-  (bundle-output-files (find-operation o 'fasl-op) s))
-
-(defmethod component-depends-on ((o load-fasl-op) (s precompiled-system))
-  (declare (ignorable o))
-  `((load-op ,s) ,@(call-next-method)))
+  #-(or ecl mkcl)
+  (defmethod perform ((o fasl-op) (c system))
+    (let* ((input-files (input-files o c))
+           (fasl-files (remove (compile-file-type) input-files :key #'pathname-type :test-not #'string=))
+           (non-fasl-files (remove (compile-file-type) input-files :key #'pathname-type :test #'string=))
+           (output-files (output-files o c))
+           (output-file (first output-files)))
+      (unless input-files (format t "WTF no input-files for ~S on ~S !???" o c))
+      (when input-files
+        (assert output-files)
+        (when non-fasl-files
+          (error "On ~A, asdf-bundle can only bundle FASL files, but these were also produced: ~S"
+                 (implementation-type) non-fasl-files))
+        (when (and (typep o 'monolithic-bundle-op)
+                   (or (monolithic-op-prologue-code o) (monolithic-op-epilogue-code o)))
+          (error "prologue-code and epilogue-code are not supported on ~A"
+                 (implementation-type)))
+        (with-staging-pathname (output-file)
+          (combine-fasls fasl-files output-file)))))
+
+  (defmethod input-files ((o load-op) (s precompiled-system))
+    (declare (ignorable o))
+    (bundle-output-files (find-operation o 'fasl-op) s))
+
+  (defmethod component-depends-on ((o load-fasl-op) (s precompiled-system))
+    (declare (ignorable o))
+    `((load-op ,s) ,@(call-next-method))))
 
-#| ;; Example use:
+  #| ;; Example use:
 (asdf:defsystem :precompiled-asdf-utils :class asdf::precompiled-system :fasl (asdf:apply-output-translations (asdf:system-relative-pathname :asdf-utils "asdf-utils.system.fasl")))
 (asdf:load-system :precompiled-asdf-utils)
 |#
 
 #+ecl
-(defmethod perform ((o bundle-op) (c system))
-  (let* ((object-files (input-files o c))
-         (output (output-files o c))
-         (bundle (first output))
-         (kind (bundle-type o)))
-    (create-image
-     bundle (append object-files (bundle-op-lisp-files o))
-     :kind kind
-     :entry-point (component-entry-point c)
-     :prologue-code
-     (when (typep o 'monolithic-bundle-op)
-       (monolithic-op-prologue-code o))
-     :epilogue-code
-     (when (typep o 'monolithic-bundle-op)
-       (monolithic-op-epilogue-code o))
-     :build-args (bundle-op-build-args o))))
+(with-upgradability ()
+  (defmethod perform ((o bundle-op) (c system))
+    (let* ((object-files (input-files o c))
+           (output (output-files o c))
+           (bundle (first output))
+           (kind (bundle-type o)))
+      (create-image
+       bundle (append object-files (bundle-op-lisp-files o))
+       :kind kind
+       :entry-point (component-entry-point c)
+       :prologue-code
+       (when (typep o 'monolithic-bundle-op)
+         (monolithic-op-prologue-code o))
+       :epilogue-code
+       (when (typep o 'monolithic-bundle-op)
+         (monolithic-op-epilogue-code o))
+       :build-args (bundle-op-build-args o)))))
 
 #+mkcl
-(progn
+(with-upgradability ()
   (defmethod perform ((o lib-op) (s system))
     (apply #'compiler::build-static-library (first output)
            :lisp-object-files (input-files o s) (bundle-op-build-args o)))
@@ -8439,13 +8769,15 @@
     (apply #'compiler::build-bundle (second output)
            :lisp-object-files (input-files o s) (bundle-op-build-args o)))
 
-  (defun* bundle-system (system &rest args &key force (verbose t) version &allow-other-keys)
+  (defun bundle-system (system &rest args &key force (verbose t) version &allow-other-keys)
     (declare (ignore force verbose version))
     (apply #'operate 'binary-op system args)))
 
 #+(or ecl mkcl)
-(defun* register-pre-built-system (name)
-  (register-system (make-instance 'system :name (coerce-name name) :source-file nil)))
+(with-upgradability ()
+  (defun register-pre-built-system (name)
+    (register-system (make-instance 'system :name (coerce-name name) :source-file nil))))
+
 ;;;; -------------------------------------------------------------------------
 ;;;; Concatenate-source
 
@@ -8471,85 +8803,86 @@
 ;;;
 ;;; Concatenate sources
 ;;;
-(defclass concatenate-source-op (bundle-op)
-  ((bundle-type :initform "lisp")))
-(defclass load-concatenated-source-op (basic-load-op operation)
-  ((bundle-type :initform :no-output-file)))
-(defclass compile-concatenated-source-op (basic-compile-op bundle-op)
-  ((bundle-type :initform :fasl)))
-(defclass load-compiled-concatenated-source-op (basic-load-op operation)
-  ((bundle-type :initform :no-output-file)))
-
-(defclass monolithic-concatenate-source-op (concatenate-source-op monolithic-op) ())
-(defclass monolithic-load-concatenated-source-op (load-concatenated-source-op monolithic-op) ())
-(defclass monolithic-compile-concatenated-source-op (compile-concatenated-source-op monolithic-op) ())
-(defclass monolithic-load-compiled-concatenated-source-op (load-compiled-concatenated-source-op monolithic-op) ())
-
-(defmethod input-files ((operation concatenate-source-op) (s system))
-  (loop :with encoding = (or (component-encoding s) *default-encoding*)
-        :with other-encodings = '()
-        :with around-compile = (around-compile-hook s)
-        :with other-around-compile = '()
-        :for c :in (required-components
-                    s :goal-operation 'compile-op
-                      :keep-operation 'compile-op
-                      :other-systems (operation-monolithic-p operation))
-        :append
-        (when (typep c 'cl-source-file)
-          (let ((e (component-encoding c)))
-            (unless (equal e encoding)
-              (pushnew e other-encodings :test 'equal)))
-          (let ((a (around-compile-hook c)))
-            (unless (equal a around-compile)
-              (pushnew a other-around-compile :test 'equal)))
-          (input-files (make-operation 'compile-op) c)) :into inputs
-        :finally
-           (when other-encodings
-             (warn "~S uses encoding ~A but has sources that use these encodings: ~A"
-                   operation encoding other-encodings))
-           (when other-around-compile
-             (warn "~S uses around-compile hook ~A but has sources that use these hooks: ~A"
-                   operation around-compile other-around-compile))
-           (return inputs)))
-
-(defmethod input-files ((o load-concatenated-source-op) (s system))
-  (direct-dependency-files o s))
-(defmethod input-files ((o compile-concatenated-source-op) (s system))
-  (direct-dependency-files o s))
-(defmethod output-files ((o compile-concatenated-source-op) (s system))
-  (let ((input (first (input-files o s))))
-    (list (compile-file-pathname input))))
-(defmethod input-files ((o load-compiled-concatenated-source-op) (s system))
-  (direct-dependency-files o s))
-
-(defmethod perform ((o concatenate-source-op) (s system))
-  (let ((inputs (input-files o s))
-        (output (output-file o s)))
-    (concatenate-files inputs output)))
-(defmethod perform ((o load-concatenated-source-op) (s system))
-  (perform-lisp-load-source o s))
-(defmethod perform ((o compile-concatenated-source-op) (s system))
-  (perform-lisp-compilation o s))
-(defmethod perform ((o load-compiled-concatenated-source-op) (s system))
-  (perform-lisp-load-fasl o s))
-
-(defmethod component-depends-on ((o concatenate-source-op) (s system))
-  (declare (ignorable o s)) nil)
-(defmethod component-depends-on ((o load-concatenated-source-op) (s system))
-  (declare (ignorable o s)) `((prepare-op ,s) (concatenate-source-op ,s)))
-(defmethod component-depends-on ((o compile-concatenated-source-op) (s system))
-  (declare (ignorable o s)) `((concatenate-source-op ,s)))
-(defmethod component-depends-on ((o load-compiled-concatenated-source-op) (s system))
-  (declare (ignorable o s)) `((compile-concatenated-source-op ,s)))
-
-(defmethod component-depends-on ((o monolithic-concatenate-source-op) (s system))
-  (declare (ignorable o s)) nil)
-(defmethod component-depends-on ((o monolithic-load-concatenated-source-op) (s system))
-  (declare (ignorable o s)) `((monolithic-concatenate-source-op ,s)))
-(defmethod component-depends-on ((o monolithic-compile-concatenated-source-op) (s system))
-  (declare (ignorable o s)) `((monolithic-concatenate-source-op ,s)))
-(defmethod component-depends-on ((o monolithic-load-compiled-concatenated-source-op) (s system))
-  (declare (ignorable o s)) `((monolithic-compile-concatenated-source-op ,s)))
+(with-upgradability ()
+  (defclass concatenate-source-op (bundle-op)
+    ((bundle-type :initform "lisp")))
+  (defclass load-concatenated-source-op (basic-load-op operation)
+    ((bundle-type :initform :no-output-file)))
+  (defclass compile-concatenated-source-op (basic-compile-op bundle-op)
+    ((bundle-type :initform :fasl)))
+  (defclass load-compiled-concatenated-source-op (basic-load-op operation)
+    ((bundle-type :initform :no-output-file)))
+
+  (defclass monolithic-concatenate-source-op (concatenate-source-op monolithic-op) ())
+  (defclass monolithic-load-concatenated-source-op (load-concatenated-source-op monolithic-op) ())
+  (defclass monolithic-compile-concatenated-source-op (compile-concatenated-source-op monolithic-op) ())
+  (defclass monolithic-load-compiled-concatenated-source-op (load-compiled-concatenated-source-op monolithic-op) ())
+
+  (defmethod input-files ((operation concatenate-source-op) (s system))
+    (loop :with encoding = (or (component-encoding s) *default-encoding*)
+          :with other-encodings = '()
+          :with around-compile = (around-compile-hook s)
+          :with other-around-compile = '()
+          :for c :in (required-components
+                      s :goal-operation 'compile-op
+                        :keep-operation 'compile-op
+                        :other-systems (operation-monolithic-p operation))
+          :append
+          (when (typep c 'cl-source-file)
+            (let ((e (component-encoding c)))
+              (unless (equal e encoding)
+                (pushnew e other-encodings :test 'equal)))
+            (let ((a (around-compile-hook c)))
+              (unless (equal a around-compile)
+                (pushnew a other-around-compile :test 'equal)))
+            (input-files (make-operation 'compile-op) c)) :into inputs
+          :finally
+             (when other-encodings
+               (warn "~S uses encoding ~A but has sources that use these encodings: ~A"
+                     operation encoding other-encodings))
+             (when other-around-compile
+               (warn "~S uses around-compile hook ~A but has sources that use these hooks: ~A"
+                     operation around-compile other-around-compile))
+             (return inputs)))
+
+  (defmethod input-files ((o load-concatenated-source-op) (s system))
+    (direct-dependency-files o s))
+  (defmethod input-files ((o compile-concatenated-source-op) (s system))
+    (direct-dependency-files o s))
+  (defmethod output-files ((o compile-concatenated-source-op) (s system))
+    (let ((input (first (input-files o s))))
+      (list (compile-file-pathname input))))
+  (defmethod input-files ((o load-compiled-concatenated-source-op) (s system))
+    (direct-dependency-files o s))
+
+  (defmethod perform ((o concatenate-source-op) (s system))
+    (let ((inputs (input-files o s))
+          (output (output-file o s)))
+      (concatenate-files inputs output)))
+  (defmethod perform ((o load-concatenated-source-op) (s system))
+    (perform-lisp-load-source o s))
+  (defmethod perform ((o compile-concatenated-source-op) (s system))
+    (perform-lisp-compilation o s))
+  (defmethod perform ((o load-compiled-concatenated-source-op) (s system))
+    (perform-lisp-load-fasl o s))
+
+  (defmethod component-depends-on ((o concatenate-source-op) (s system))
+    (declare (ignorable o s)) nil)
+  (defmethod component-depends-on ((o load-concatenated-source-op) (s system))
+    (declare (ignorable o s)) `((prepare-op ,s) (concatenate-source-op ,s)))
+  (defmethod component-depends-on ((o compile-concatenated-source-op) (s system))
+    (declare (ignorable o s)) `((concatenate-source-op ,s)))
+  (defmethod component-depends-on ((o load-compiled-concatenated-source-op) (s system))
+    (declare (ignorable o s)) `((compile-concatenated-source-op ,s)))
+
+  (defmethod component-depends-on ((o monolithic-concatenate-source-op) (s system))
+    (declare (ignorable o s)) nil)
+  (defmethod component-depends-on ((o monolithic-load-concatenated-source-op) (s system))
+    (declare (ignorable o s)) `((monolithic-concatenate-source-op ,s)))
+  (defmethod component-depends-on ((o monolithic-compile-concatenated-source-op) (s system))
+    (declare (ignorable o s)) `((monolithic-concatenate-source-op ,s)))
+  (defmethod component-depends-on ((o monolithic-load-compiled-concatenated-source-op) (s system))
+    (declare (ignorable o s)) `((monolithic-compile-concatenated-source-op ,s))))
 
 ;;;; -------------------------------------------------------------------------
 ;;; Backward-compatible interfaces
@@ -8568,124 +8901,145 @@
    #:operation-forced
    #:operation-on-failure
    #:operation-on-warnings
+   #:component-property
    #:run-shell-command
    #:system-definition-pathname))
 (in-package :asdf/backward-interface)
 
-(define-condition operation-error (error) ;; Bad, backward-compatible name
-  ;; Used by SBCL, cffi-tests, clsql-mysql, clsql-uffi, qt, elephant, uffi-tests, sb-grovel
-  ((component :reader error-component :initarg :component)
-   (operation :reader error-operation :initarg :operation))
-  (:report (lambda (c s)
+(with-upgradability ()
+  (define-condition operation-error (error) ;; Bad, backward-compatible name
+    ;; Used by SBCL, cffi-tests, clsql-mysql, clsql-uffi, qt, elephant, uffi-tests, sb-grovel
+    ((component :reader error-component :initarg :component)
+     (operation :reader error-operation :initarg :operation))
+    (:report (lambda (c s)
                (format s (compatfmt "~@<~A while invoking ~A on ~A~@:>")
                        (type-of c) (error-operation c) (error-component c)))))
-(define-condition compile-error (operation-error) ())
-(define-condition compile-failed (compile-error) ())
-(define-condition compile-warned (compile-error) ())
-
-(defun* component-load-dependencies (component)
-  ;; Old deprecated name for the same thing. Please update your software.
-  (component-sibling-dependencies component))
-
-(defgeneric* operation-forced (operation)) ;; Used by swank.asd for swank-loader.
-(defmethod operation-forced ((o operation)) (getf (operation-original-initargs o) :force))
-
-(defgeneric* operation-on-warnings (operation))
-(defgeneric* operation-on-failure (operation))
-#-gcl2.6 (defgeneric* (setf operation-on-warnings) (x operation))
-#-gcl2.6 (defgeneric* (setf operation-on-failure) (x operation))
-(defmethod operation-on-warnings ((o operation))
-  (declare (ignorable o)) *compile-file-warnings-behaviour*)
-(defmethod operation-on-failure ((o operation))
-  (declare (ignorable o)) *compile-file-failure-behaviour*)
-(defmethod (setf operation-on-warnings) (x (o operation))
-  (declare (ignorable o)) (setf *compile-file-warnings-behaviour* x))
-(defmethod (setf operation-on-failure) (x (o operation))
-  (declare (ignorable o)) (setf *compile-file-failure-behaviour* x))
-
-(defun* system-definition-pathname (x)
-  ;; As of 2.014.8, we mean to make this function obsolete,
-  ;; but that won't happen until all clients have been updated.
-  ;;(cerror "Use ASDF:SYSTEM-SOURCE-FILE instead"
-  "Function ASDF:SYSTEM-DEFINITION-PATHNAME is obsolete.
+  (define-condition compile-error (operation-error) ())
+  (define-condition compile-failed (compile-error) ())
+  (define-condition compile-warned (compile-error) ())
+
+  (defun component-load-dependencies (component)
+    ;; Old deprecated name for the same thing. Please update your software.
+    (component-sibling-dependencies component))
+
+  (defgeneric operation-forced (operation)) ;; Used by swank.asd for swank-loader.
+  (defmethod operation-forced ((o operation)) (getf (operation-original-initargs o) :force))
+
+  (defgeneric operation-on-warnings (operation))
+  (defgeneric operation-on-failure (operation))
+  #-gcl2.6 (defgeneric (setf operation-on-warnings) (x operation))
+  #-gcl2.6 (defgeneric (setf operation-on-failure) (x operation))
+  (defmethod operation-on-warnings ((o operation))
+    (declare (ignorable o)) *compile-file-warnings-behaviour*)
+  (defmethod operation-on-failure ((o operation))
+    (declare (ignorable o)) *compile-file-failure-behaviour*)
+  (defmethod (setf operation-on-warnings) (x (o operation))
+    (declare (ignorable o)) (setf *compile-file-warnings-behaviour* x))
+  (defmethod (setf operation-on-failure) (x (o operation))
+    (declare (ignorable o)) (setf *compile-file-failure-behaviour* x))
+
+  (defun system-definition-pathname (x)
+    ;; As of 2.014.8, we mean to make this function obsolete,
+    ;; but that won't happen until all clients have been updated.
+    ;;(cerror "Use ASDF:SYSTEM-SOURCE-FILE instead"
+    "Function ASDF:SYSTEM-DEFINITION-PATHNAME is obsolete.
 It used to expose ASDF internals with subtle differences with respect to
 user expectations, that have been refactored away since.
 We recommend you use ASDF:SYSTEM-SOURCE-FILE instead
 for a mostly compatible replacement that we're supporting,
 or even ASDF:SYSTEM-SOURCE-DIRECTORY or ASDF:SYSTEM-RELATIVE-PATHNAME
 if that's whay you mean." ;;)
-  (system-source-file x))
+    (system-source-file x)))
 
 
 ;;;; ASDF-Binary-Locations compatibility
-
-(defun* enable-asdf-binary-locations-compatibility
-    (&key
-     (centralize-lisp-binaries nil)
-     (default-toplevel-directory
-         (subpathname (user-homedir-pathname) ".fasls/")) ;; Use ".cache/common-lisp/" instead ???
-     (include-per-user-information nil)
-     (map-all-source-files (or #+(or clisp ecl mkcl) t nil))
-     (source-to-target-mappings nil)
-     (file-types (list (compile-file-type)
-                         #+ecl (compile-file-type :type :object)
-                         #+mkcl (compile-file-type :fasl-p nil)
-                         #+clisp "lib" #+sbcl "cfasl"
-                         #+sbcl "sbcl-warnings" #+clozure "ccl-warnings")))
-  #+(or clisp ecl mkcl)
-  (when (null map-all-source-files)
-    (error "asdf:enable-asdf-binary-locations-compatibility doesn't support :map-all-source-files nil on CLISP, ECL and MKCL"))
-  (let* ((patterns (if map-all-source-files (list *wild-file*)
-                       (loop :for type :in file-types
-                             :collect (make-pathname :type type :defaults *wild-file*))))
-         (destination-directory
-          (if centralize-lisp-binaries
-              `(,default-toplevel-directory
-                ,@(when include-per-user-information
-                        (cdr (pathname-directory (user-homedir-pathname))))
-                :implementation ,*wild-inferiors*)
-              `(:root ,*wild-inferiors* :implementation))))
-    (initialize-output-translations
-     `(:output-translations
-       , at source-to-target-mappings
-       #+abcl (#p"jar:file:/**/*.jar!/**/*.*" (:function translate-jar-pathname))
-       #+abcl (#p"/___jar___file___root___/**/*.*" (, at destination-directory))
-       ,@(loop :for pattern :in patterns
-               :collect `((:root ,*wild-inferiors* ,pattern)
-                          (, at destination-directory ,pattern)))
-       (t t)
-       :ignore-inherited-configuration))))
-
-(defmethod operate :before (operation-class system &rest args &key &allow-other-keys)
-  (declare (ignorable operation-class system args))
-  (when (find-symbol* '#:output-files-for-system-and-operation :asdf nil)
-    (error "ASDF 2 is not compatible with ASDF-BINARY-LOCATIONS, which you are using.
+;; This remains supported for legacy user, but not recommended for new users.
+(with-upgradability ()
+  (defun enable-asdf-binary-locations-compatibility
+      (&key
+       (centralize-lisp-binaries nil)
+       (default-toplevel-directory
+        (subpathname (user-homedir-pathname) ".fasls/")) ;; Use ".cache/common-lisp/" instead ???
+       (include-per-user-information nil)
+       (map-all-source-files (or #+(or clisp ecl mkcl) t nil))
+       (source-to-target-mappings nil)
+       (file-types `(,(compile-file-type)
+                     "build-report"
+                     #+ecl (compile-file-type :type :object)
+                     #+mkcl (compile-file-type :fasl-p nil)
+                     #+clisp "lib" #+sbcl "cfasl"
+                     #+sbcl "sbcl-warnings" #+clozure "ccl-warnings")))
+    #+(or clisp ecl mkcl)
+    (when (null map-all-source-files)
+      (error "asdf:enable-asdf-binary-locations-compatibility doesn't support :map-all-source-files nil on CLISP, ECL and MKCL"))
+    (let* ((patterns (if map-all-source-files (list *wild-file*)
+                         (loop :for type :in file-types
+                               :collect (make-pathname :type type :defaults *wild-file*))))
+           (destination-directory
+             (if centralize-lisp-binaries
+                 `(,default-toplevel-directory
+                   ,@(when include-per-user-information
+                       (cdr (pathname-directory (user-homedir-pathname))))
+                   :implementation ,*wild-inferiors*)
+                 `(:root ,*wild-inferiors* :implementation))))
+      (initialize-output-translations
+       `(:output-translations
+         , at source-to-target-mappings
+         #+abcl (#p"jar:file:/**/*.jar!/**/*.*" (:function translate-jar-pathname))
+         #+abcl (#p"/___jar___file___root___/**/*.*" (, at destination-directory))
+         ,@(loop :for pattern :in patterns
+                 :collect `((:root ,*wild-inferiors* ,pattern)
+                            (, at destination-directory ,pattern)))
+         (t t)
+         :ignore-inherited-configuration))))
+
+  (defmethod operate :before (operation-class system &rest args &key &allow-other-keys)
+    (declare (ignorable operation-class system args))
+    (when (find-symbol* '#:output-files-for-system-and-operation :asdf nil)
+      (error "ASDF 2 is not compatible with ASDF-BINARY-LOCATIONS, which you are using.
 ASDF 2 now achieves the same purpose with its builtin ASDF-OUTPUT-TRANSLATIONS,
 which should be easier to configure. Please stop using ASDF-BINARY-LOCATIONS,
 and instead use ASDF-OUTPUT-TRANSLATIONS. See the ASDF manual for details.
 In case you insist on preserving your previous A-B-L configuration, but
 do not know how to achieve the same effect with A-O-T, you may use function
 ASDF:ENABLE-ASDF-BINARY-LOCATIONS-COMPATIBILITY as documented in the manual;
-call that function where you would otherwise have loaded and configured A-B-L.")))
+call that function where you would otherwise have loaded and configured A-B-L."))))
 
 
-;;;; run-shell-command
-;;
-;; WARNING! The function below is dysfunctional and deprecated.
+;;; run-shell-command
+;; WARNING! The function below is not just deprecated but also dysfunctional.
 ;; Please use asdf/run-program:run-program instead.
-;;
-(defun* run-shell-command (control-string &rest args)
-  "Interpolate ARGS into CONTROL-STRING as if by FORMAT, and
+(with-upgradability ()
+  (defun run-shell-command (control-string &rest args)
+    "Interpolate ARGS into CONTROL-STRING as if by FORMAT, and
 synchronously execute the result using a Bourne-compatible shell, with
 output to *VERBOSE-OUT*.  Returns the shell's exit code.
 
 PLEASE DO NOT USE.
 Deprecated function, for backward-compatibility only.
 Please use ASDF-DRIVER:RUN-PROGRAM instead."
-  (let ((command (apply 'format nil control-string args)))
-    (asdf-message "; $ ~A~%" command)
-    (run-program command :force-shell t :ignore-error-status t :output *verbose-out*)))
-
+    (let ((command (apply 'format nil control-string args)))
+      (asdf-message "; $ ~A~%" command)
+      (run-program command :force-shell t :ignore-error-status t :output *verbose-out*))))
+
+(with-upgradability ()
+  (defvar *asdf-verbose* nil)) ;; backward-compatibility with ASDF2 only. Unused.
+
+;; backward-compatibility methods. Do NOT use in new code. NOT SUPPORTED.
+(with-upgradability ()
+  (defgeneric component-property (component property))
+  (defgeneric (setf component-property) (new-value component property))
+
+  (defmethod component-property ((c component) property)
+    (cdr (assoc property (slot-value c 'properties) :test #'equal)))
+
+  (defmethod (setf component-property) (new-value (c component) property)
+    (let ((a (assoc property (slot-value c 'properties) :test #'equal)))
+      (if a
+          (setf (cdr a) new-value)
+          (setf (slot-value c 'properties)
+                (acons property new-value (slot-value c 'properties)))))
+    new-value))
 ;;;; ---------------------------------------------------------------------------
 ;;;; Handle ASDF package upgrade, including implementation-dependent magic.
 
@@ -8735,6 +9089,7 @@
    #:monolithic-compile-concatenated-source-op
    #:monolithic-load-compiled-concatenated-source-op
    #:operation-monolithic-p
+   #:required-components
 
    #:component #:parent-component #:child-component #:system #:module
    #:file-component #:source-file #:c-source-file #:java-source-file
@@ -8756,6 +9111,7 @@
    #:component-depends-on ; backward-compatible name rather than action-depends-on
    #:module-components ; backward-compatibility
    #:operation-on-warnings #:operation-on-failure ; backward-compatibility
+   #:component-property ; backward-compatibility
 
    #:system-description
    #:system-long-description
@@ -8766,6 +9122,11 @@
    #:system-source-file
    #:system-source-directory
    #:system-relative-pathname
+   #:system-homepage
+   #:system-bug-tracker
+   #:system-developers-email
+   #:system-long-name
+   #:system-source-control
    #:map-systems
 
    #:*system-definition-search-functions*   ; variables
@@ -8774,7 +9135,7 @@
    #:*compile-file-failure-behaviour*
    #:*resolve-symlinks*
    #:*load-system-operation*
-   #:*asdf-verbose*
+   #:*asdf-verbose* ;; unused. For backward-compatibility only.
    #:*verbose-out*
 
    #:asdf-version
@@ -8855,53 +9216,46 @@
 
 ;;;; Hook ASDF into the implementation's REQUIRE and other entry points.
 
-#+(or abcl clisp clozure cmu ecl mkcl sbcl)
-(if-let (x (and #+clisp (find-symbol* '#:*module-provider-functions* :custom nil)))
-  (eval `(pushnew 'module-provide-asdf
-                  #+abcl sys::*module-provider-functions*
-                  #+clisp ,x
-                  #+clozure ccl:*module-provider-functions*
-                  #+(or cmu ecl) ext:*module-provider-functions*
-                  #+mkcl mk-ext:*module-provider-functions*
-                  #+sbcl sb-ext:*module-provider-functions*)))
-
-#+(or ecl mkcl)
-(progn
-  (pushnew '("fasb" . si::load-binary) si:*load-hooks* :test 'equal :key 'car)
+(with-upgradability ()
+  #+(or abcl clisp clozure cmu ecl mkcl sbcl)
+  (if-let (x (and #+clisp (find-symbol* '#:*module-provider-functions* :custom nil)))
+    (eval `(pushnew 'module-provide-asdf
+                    #+abcl sys::*module-provider-functions*
+                    #+clisp ,x
+                    #+clozure ccl:*module-provider-functions*
+                    #+(or cmu ecl) ext:*module-provider-functions*
+                    #+mkcl mk-ext:*module-provider-functions*
+                    #+sbcl sb-ext:*module-provider-functions*)))
 
-  #+(or (and ecl win32) (and mkcl windows))
-  (unless (assoc "asd" #+ecl ext:*load-hooks* #+mkcl si::*load-hooks* :test 'equal)
-    (appendf #+ecl ext:*load-hooks* #+mkcl si::*load-hooks* '(("asd" . si::load-source))))
-
-  (setf #+ecl ext:*module-provider-functions* #+mkcl mk-ext::*module-provider-functions*
-        (loop :for f :in #+ecl ext:*module-provider-functions*
-          #+mkcl mk-ext::*module-provider-functions*
-          :unless (eq f 'module-provide-asdf)
-          :collect #'(lambda (name)
-                       (let ((l (multiple-value-list (funcall f name))))
-                         (and (first l) (register-pre-built-system (coerce-name name)))
-                         (values-list l))))))
+  #+(or ecl mkcl)
+  (progn
+    (pushnew '("fasb" . si::load-binary) si:*load-hooks* :test 'equal :key 'car)
 
+    #+(or (and ecl win32) (and mkcl windows))
+    (unless (assoc "asd" #+ecl ext:*load-hooks* #+mkcl si::*load-hooks* :test 'equal)
+      (appendf #+ecl ext:*load-hooks* #+mkcl si::*load-hooks* '(("asd" . si::load-source))))
+
+    (setf #+ecl ext:*module-provider-functions* #+mkcl mk-ext::*module-provider-functions*
+          (loop :for f :in #+ecl ext:*module-provider-functions*
+                #+mkcl mk-ext::*module-provider-functions*
+                :unless (eq f 'module-provide-asdf)
+                  :collect #'(lambda (name)
+                               (let ((l (multiple-value-list (funcall f name))))
+                                 (and (first l) (register-pre-built-system (coerce-name name)))
+                                 (values-list l)))))))
 
-;;;; Cleanups after hot-upgrade.
-;; Things to do in case we're upgrading from a previous version of ASDF.
-;; See https://bugs.launchpad.net/asdf/+bug/485687
-;;
-;; If a previous version of ASDF failed to read some configuration, try again.
-(when *ignored-configuration-form*
-  (clear-configuration)
-  (setf *ignored-configuration-form* nil))
 
 ;;;; Done!
-
-#+allegro
-(eval-when (:compile-toplevel :execute)
+(with-upgradability ()
+  #+allegro
   (when (boundp 'excl:*warn-on-nested-reader-conditionals*)
-    (setf excl:*warn-on-nested-reader-conditionals* asdf/common-lisp::*acl-warn-save*)))
+    (setf excl:*warn-on-nested-reader-conditionals* asdf/common-lisp::*acl-warn-save*))
+
+  (dolist (f '(:asdf :asdf2 :asdf3)) (pushnew f *features*))
 
-(dolist (f '(:asdf :asdf2 :asdf3)) (pushnew f *features*))
+  (provide :asdf)
 
-(provide :asdf)
+  (cleanup-upgraded-asdf))
 
 (when *load-verbose*
   (asdf-message ";; ASDF, version ~a~%" (asdf-version)))




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