bug#30756: gcc7 doesn't find stdlib.h

[Mark H Weaver]

address@hidden (Ludovic Courtès) writes:

> Mark H Weaver <address@hidden> skribis:
>
>> On my own private branch, I worked around this problem by adding
>> "-idirafter <LIBC>/include" to CXXFLAGS, but of course it's not a proper
>> fix.  My workaround happens to be in Savannah on the
>> 'reproduce-bug-29774' branch:
>>
>>   
>> https://git.savannah.gnu.org/cgit/guix.git/commit/?h=reproduce-bug-29774&id=87022e2666c5e68e865eb160a4bd8e9cdcc1a955
>
> Perhaps we could achieve the same effect by adding “-idirafter
> LIBC/include” to the default spec file, under ‘cpp_options’?
> (We’d achieve that by modifying the value of ‘cpp_options’ in
> gcc/gcc.c.)

I guess that it might be better to avoid using -idirafter and instead
pay attention to the order in which the normal include search paths are
populated, and in particular for LIBC to last, but maybe that would be
awkward to arrange, dunno.

       Mark