[asdf-devel] asdf loading error error

[Robert Goldman]

Faré wrote:
> On Sat, Feb 22, 2014 at 3:26 PM, Cyrus Harmon <ch-lisp at bobobeach.com> wrote:
>> While trying to load and asdf system that generates an error (that’s another story, presumably an abcl-contrib problem), I get the following error:
>>
>> Error while trying to load definition for system abcl-cdk from
>> pathname /Users/sly/projects/abcl-cdk/abcl-cdk.asd:
>>    There is no applicable method for the generic function #<STANDARD-GENERIC-FUNCTION ASDF/SYSTEM:BUILTIN-SYSTEM-P {4DE3AFA9}> when called with arguments ((NIL)).
>>    [Condition of type ASDF/FIND-SYSTEM:LOAD-SYSTEM-DEFINITION-ERROR]
>>
> There's an error while reporting a warning (warning about your system
> having a bad version string).
> I suggest you add this method in system.lisp after defclass system:
>  (defmethod builtin-system-p ((x null)) nil)
> Does it help?
>
> Robert, do you want me to commit that?

I'd like to understand this patch better before we push it.

Why is it that having a method on NIL is right?  Doesn't this just mask a bug where we are incorrectly treating NIL as if it's a system designator?

What's the cause for trying to ask if NIL is a built in system?  Presumably some system lookup returned NIL, right?  If so, why wasn't that trapped as an error?

thanks,
r