Re: [gtk-list] Re: Poblem compiling Glib 1.2.4

[Tim Janik <timj gtk org>]

On Wed, 25 Aug 1999, Kevin Handy wrote:

> I got the FAQ out of the source code for GCC-2.95.1, and seems
> to be available at http://egcs.cygnus.com/faq.html , but the
> section in question reads as follows:
> 
> FD_ZERO macro
>    The FD_ZERO macro in (e.g.) libc-5.4.46 is incorrect. It uses
>    [72]invalid asm clobbers. The following rewrite by Ulrich Drepper
>    <drepper@cygnus.com> should fix this for glibc 2.0:
> 
>   # define __FD_ZERO(fdsetp) \
>     do { \
>       int __d0, __d1; \
>     __asm__ __volatile__ ("cld; rep; stosl" \
>: "=m" (((__fd_mask *) \
>                                   (fdsetp))[__FDELT (__FD_SETSIZE)]), \
>                             "=&c" (__d0), "=&D" (__d1) \
>: "a" (0), "1" (sizeof (__fd_set) \
>                                           / sizeof (__fd_mask)), \
>                             "2" ((__fd_mask *) (fdsetp)) \
>: "memory"); \
>     } while (0)     
> 
> The error generated reads

the FAQ clearly states that this is a libc5+gcc2.95 bug (read the "asm clobber"
section on this). since libc5 is fairly uncommon these days, and you actually
bothered updating your compiler, i guess the best fix is to update to glibc
as well. alternatively you can of course patch your libc include files to
use the above __FD_ZERO definition, fixing this in glib is the wrong approach,
as you'll encounter the same problem when compiling other programs.

---
ciaoTJ