[cffi-devel] Linking CL to fortran-77 via cffi

[Martin Simmons]

>>>>> On Thu, 29 Dec 2011 21:19:15 -0500, Mirko Vukovic said:
> 
> Hello,
> 
> Several projects (lla, blapack among them) link common lisp (cl) to fortran
> 77 (f77)code.  Unfortunately, being totally unfamiliar with cffi, I was
> having trouble using those packages to learn how to link cl to other f77
> code.
> 
> To learn more about calling f77 code from CL, I assembled a bunch of simple
> examples (using cygwin+clisp+gfortran).to show how to pass values of
> various types to f77.
> 
> I have put up the examples on https://github.com/mirkov/cffi-f77.  I tried
> to add enough documentation to make the package easily understandable.
> 
> I hope this proves useful to others.  I would appreciate comments regarding
> errors and improvements.

I tested the code in LispWorks on 64-bit Linux and found the following changes
useful.

Avoid hardwired paths:

diff --git a/library-ops.lisp b/library-ops.lisp
index 63358e1..2c2e6b9 100755
--- a/library-ops.lisp
+++ b/library-ops.lisp
@@ -27,7 +27,7 @@
 (defun link-lib ()
   "Link to the foreign library"
   (setf *lib*
-	(load-foreign-library #P"/home/977315/my-software-add-ons/my-lisp/cffi+f77/library.dll")))
+	(load-foreign-library (asdf:system-relative-pathname "cffi+f77" "library.dll"))))
 
 (defun unlink-lib ()
   "Unlink from the foreign library"


Need -fPIC for successful linking on 64-bit Linux:

diff --git a/makefile b/makefile
index 3db9e80..1b542d6 100755
--- a/makefile
+++ b/makefile
@@ -3,7 +3,7 @@ fortran = gfortran
 objs = simple_example.o subroutines.o
 
 %.o : %.f
-	$(fortran) -c $< -o $@
+	$(fortran) -c -fPIC $< -o $@
 
 special : clean
 clean :


Enhancement to the instructions:

diff --git a/readme.org b/readme.org
index 9729387..b216a9d 100755
--- a/readme.org
+++ b/readme.org
@@ -73,5 +73,6 @@ make library.dll
 
   The examples correctness can be verified by running unit tests:
 #+begin_src lisp
+(in-package #:cffi+f77)
 (run-tests)
 #+end_src


__Martin