Hi,

I found a ASDF-related CFFI bug a couple of days ago. Can anyone think of a good way of fixing it?

;;; Declare the .o and .so files as compilation outputs,
;;; so they get picked up by bundle operations.
#.(when (version<= "3.1.6" (asdf-version))
    '(defmethod output-files ((op compile-op) (c wrapper-file))
      (destructuring-bind (generated-lisp lib-file c-file o-file) (output-files 'process-op c)
        (declare (ignore generated-lisp c-file))
        (multiple-value-bind (files translatedp) (call-next-method)
          (values (append files (list lib-file o-file)) translatedp)))))

As a result inputs and outputs of the ops look like this:
process-op:
  input: wrapper-file
  output: bindings-file.lisp file.c FILE.O FILE.SO

compile-op:
  input: bindings-file.lisp
  output: bindings-file.fasl FILE.O FILE.SO

The problem is that process-op generates file.o and file.so before it generates bindings-file.lisp. Thus compile-op gets re-executed all the time, because its output files file.o and file.so are always older than its input file bindings-file.lisp. And an execution of the compile-op does not change anything, because it does not really generate .o and .so.
One way to fix it would be to "touch" .o and .so to get the right order of file modification times, but there may be a better way.

CFFI bug report: https://bugs.launchpad.net/cffi/+bug/1889491

Thanks,
Ilya