Re: Problem with removing <config.h> from gen-scmconfig when cross-compiling

[Mark H Weaver <mhw@netris.org>]

ludo@gnu.org (Ludovic Courtès) writes:

> Mark H Weaver <mhw@netris.org> skribis:
>
>> Commit 8cb0d6d7fa9aaac316c29a64c541336b51b6f93d "build: Don't include
>> <config.h> in native programs when cross-compiling." apparently broke
>> cross-compiling.  Madsy on #guile, who successfully cross-compiled
>> e1bb79f for mingw, ran into this problem with 21a7ba9:
>>
>> make[1]: Entering directory `/home/madsy/mingw/home/madsy/test/guile-2.0.9.f239-21a7b-dirty/libguile'
>>   GEN      gen-scmconfig.o
>> gen-scmconfig.c: In function 'main':
>> gen-scmconfig.c:245:39: error: 'SIZEOF_CHAR' undeclared (first use in this function)
>> gen-scmconfig.c:245:39: note: each undeclared identifier is reported only once for each function it appears in
>
> Arrgggh, indeed, sorry!
>
> We should revert that patch, but then I’m not sure how to properly fix
> the initial problem, which is that gen-scmconfig.c ends up using
> Gnulib’s <stdio.h> etc.

Madsy told me that the only problem he had when cross-compiling e1bb79f
was in c-tokenize.c.  He worked around it by simply removing "#include
<config.h>" from that file.  gen-scmconfig.c was not a problem.

The specific problem was that c-tokenize.c includes <stdlib.h>,
but gen-scmconfig.c doesn't include <stdlib.h>.

I agree that this is fragile and should be reworked somehow, but for
2.0.10, I wonder if we could just revert the part of 8cb0d6d having to
do with gen-scmconfig.c.

What do you think?

> Could Madsy check, after reverting the patch, if it works when doing
> things in this order:
>
>   /* Include the “real” headers.  */
>   #include <stdio.h>
>   #include <stdlib.h>
>
>   /* Get the useful definitions.  */
>   #include <config.h>

My impression is that we can't rely on this level of help from Madsy, at
least not in the short term.

Didn't hydra.nixos.org do MinGW cross-builds of Guile in the past?
If so, what happened to those?

     Mark