[Bug c/80409] Document that va_arg(ap, void*) can be used to consume any pointer argument

[egallager at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80409

Eric Gallager <egallager at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |documentation, easyhack
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2017-08-01
                 CC|                            |egallager at gcc dot gnu.org
     Ever confirmed|0                           |1

--- Comment #4 from Eric Gallager <egallager at gcc dot gnu.org> ---
(In reply to joseph@codesourcery.com from comment #3)
> On Wed, 12 Apr 2017, pascal_cuoq at hotmail dot com wrote:
> 
> > Since the open-source world divides the C compilation platform described by
> > the C standard into C compilers (Clang, GCC) and standard libraries (Glibc,
> > musl, ...), with the implementation of varargs on the compiler side and the
> > implementation of scanf on the standard library side, it would make sense to
> > document that on target platforms where the representation of pointers is
> > uniform, the compilers allow va_arg(ap, void*) to consume any pointer
> > argument.
> 
> Note that this is documented in POSIX (XSI-shaded, in the specification of 
> stdarg.h).

So in that case it should be easy to just put a reference to the POSIX docs in
the GCC docs