Re: [PATCH for 7.2?] target/i386: Remove compilation errors when -Werror=maybe-uninitialized

[Stefan Hajnoczi]

On Wed, 7 Dec 2022 at 08:31, Eric Auger <eric.auger@redhat.com> wrote:
> On 12/7/22 14:24, Eric Auger wrote:
> > Initialize r0-3 to avoid compilation errors when
> > -Werror=maybe-uninitialized is used
> >
> > ../target/i386/ops_sse.h: In function ‘helper_vpermdq_ymm’:
> > ../target/i386/ops_sse.h:2495:13: error: ‘r3’ may be used uninitialized in 
> > this function [-Werror=maybe-uninitialized]
> >  2495 |     d->Q(3) = r3;
> >       |     ~~~~~~~~^~~~
> > ../target/i386/ops_sse.h:2494:13: error: ‘r2’ may be used uninitialized in 
> > this function [-Werror=maybe-uninitialized]
> >  2494 |     d->Q(2) = r2;
> >       |     ~~~~~~~~^~~~
> > ../target/i386/ops_sse.h:2493:13: error: ‘r1’ may be used uninitialized in 
> > this function [-Werror=maybe-uninitialized]
> >  2493 |     d->Q(1) = r1;
> >       |     ~~~~~~~~^~~~
> > ../target/i386/ops_sse.h:2492:13: error: ‘r0’ may be used uninitialized in 
> > this function [-Werror=maybe-uninitialized]
> >  2492 |     d->Q(0) = r0;
> >       |     ~~~~~~~~^~~~
> >
> > Signed-off-by: Eric Auger <eric.auger@redhat.com>
> > Fixes: 790684776861 ("target/i386: reimplement 0x0f 0x3a, add AVX")
> >
> > ---
> >
> > Am I the only one getting this? Or anything wrong in my setup.
>
> With Stefan's correct address. Forgive me for the noise.

When is -Wmaybe-uninitialized used? QEMU's build system doesn't set
it. Unless it's automatically set by meson this must be a manual
--extra-cflags= option you set.

If you added it manually then let's fix this in 8.0 since it's not
tested/supported and very few people will see this issue.

Stefan