Re: [PATCH v2] target/i386: Remove compilation errors when -Werror=maybe-uninitialized

[Paolo Bonzini <pbonzini@redhat.com>]

On 12/21/22 17:36, Eric Auger wrote:
> To avoid compilation errors when -Werror=maybe-uninitialized is used,
> replace 'case 3' by 'default'.
> 
> Otherwise we get:
> 
> ../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>
> Suggested-by: Stefan Weil <sw@weilnetz.de>
> Fixes: 790684776861 ("target/i386: reimplement 0x0f 0x3a, add AVX")
> ---
>   target/i386/ops_sse.h | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/target/i386/ops_sse.h b/target/i386/ops_sse.h
> index 3cbc36a59d..c442c8c10c 100644
> --- a/target/i386/ops_sse.h
> +++ b/target/i386/ops_sse.h
> @@ -2466,7 +2466,7 @@ void helper_vpermdq_ymm(Reg *d, Reg *v, Reg *s, uint32_t order)
>           r0 = s->Q(0);
>           r1 = s->Q(1);
>           break;
> -    case 3:
> +    default:
>           r0 = s->Q(2);
>           r1 = s->Q(3);
>           break;
> @@ -2484,7 +2484,7 @@ void helper_vpermdq_ymm(Reg *d, Reg *v, Reg *s, uint32_t order)
>           r2 = s->Q(0);
>           r3 = s->Q(1);
>           break;
> -    case 3:
> +    default:
>           r2 = s->Q(2);
>           r3 = s->Q(3);
>           break;

Queued, but this compiler sucks. :)

Paolo