Re: AC_PROG_CC fails when target C library is missing fopen

[Paolo Bonzini]

> > commit 1bf41a68050d04c57be42a5cb334294913684933
> > Author: Paolo Bonzini<address@hidden>
> > Date:   Fri Aug 7 16:40:34 2009 +0200
> >
> >      use a separate program to test whether the compiler works
> >
> >      * lib/autoconf/c.m4 (_AC_LANG_NULL_PROGRAM(C)): New.
> >      * lib/autoconf/erlang.m4 (_AC_LANG_NULL_PROGRAM(Erlang)): New.
> >      * lib/autoconf/lang.m4 (AC_LANG_DEFINE): Copy _AC_LANG_NULL_PROGRAM.
> >      (_AC_LANG_NULL_PROGRAM(), _AC_LANG_NULL_PROGRAM): New.
> >      (_AC_COMPILER_EXEEXT_DEFAULT): Print here "whether the xyz compiler works",
> >      before exiting.
> >      (_AC_COMPILER_EXEEXT_WORKS): Merge into _AC_COMPILER_EXEEXT_CROSS, remove
> >      the "whether the xyz compiler works" message, use conftest$ac_cv_exeext
> >      instead of $ac_file.
> >      (_AC_COMPILER_EXEEXT): Try _AC_COMPILER_EXEEXT_DEFAULT using the
> >      null program, and clean conftest.out only after _AC_COMPILER_EXEEXT_CROSS.
>
> Doesn't this patch have to introduce _AC_LANG_NULL_PROGRAM(...) for
> F77 and FC?

No, the default is empty and defined in _AC_LANG_NULL_PROGRAM().

If packages override the toplevel _AC_COMPILER_EXEEXT that should be 
fine.  The problem is whether they muddle with its sub-macros.

Paolo