This is the mail archive of the
gcc-help@gcc.gnu.org
mailing list for the GCC project.
Re: gcc -march=nocona -mtune=nocona --help=target
- From: Alexander Monakov <amonakov at ispras dot ru>
- To: Ian Lance Taylor <iant at google dot com>
- Cc: Oleg Kravchenko <oleg at kaa dot org dot ua>, gcc-help at gcc dot gnu dot org
- Date: Wed, 22 Apr 2009 18:04:19 +0400
- Subject: Re: gcc -march=nocona -mtune=nocona --help=target
- References: <49EED736.1030505@kaa.org.ua> <m3d4b4ak8w.fsf@google.com>
On Wed, Apr 22, 2009 at 06:30:39AM -0700, Ian Lance Taylor wrote:
> Oleg Kravchenko <oleg@kaa.org.ua> writes:
>
> > Why gcc say what mmx, sse, sse2 is disabled?
> >
> > $ gcc -march=nocona -mtune=nocona --help=target
>
> They are disabled because you didn't explicitly request them.
>
> Ian
Sorry, Ian, but is this behaviour really intended? These extensions are
enabled by gcc/config/i386/i386.c:override_options() for -march=nocona, and if
one uses -fverbose-asm, they are really listed as enabled there. IMHO, in
this situation behaviour of -Q --help=target and -fverbose-asm seems
contradictory and a bit confusing to the user.
Perhaps GCC could do better by calling OVERRIDE_OPTIONS (currently in
toplev.c:process_options()) before calling decode_options()? Is it worth a
bugzilla entry?
Thanks.
--
Alexander Monakov