From: Richard Biener <richard.guenther@gmail.com>
To: "Uecker, Martin" <Martin.Uecker@med.uni-goettingen.de>
Cc: "gcc@gcc.gnu.org" <gcc@gcc.gnu.org>
Subject: Re: TBAA bug?
Date: Tue, 27 Jul 2021 10:02:34 +0200 [thread overview]
Message-ID: <CAFiYyc2AaHU7aV-pgmMB8qjz9xHJTiTZRks_keNyuQF1A4g1zQ@mail.gmail.com> (raw)
In-Reply-To: <1a066477a05b80f7edb50d71c495f63c10e8e74a.camel@med.uni-goettingen.de>
On Sun, Jul 25, 2021 at 1:58 PM Uecker, Martin
<Martin.Uecker@med.uni-goettingen.de> wrote:
>
>
>
> Hi Richard,
>
> here is another case where it seems that TBAA goes
> wrong. Since this is not in a loop, it seems this
> is something else than what we discussed. Is
> this a known issue?
>
> Best,
> Martin
>
>
> #include <stdio.h>
> #include <stdlib.h>
>
> union u {
> long x;
> long long y;
> };
>
> __attribute__((noinline,noclone))
> long test(long *px, long long *py, union u *pu)
> {
> *px = 0;
> *py = 1;
>
> long xy = pu->y;
> pu->x = xy;
>
> return *px;
> }
>
> int main(void)
> {
> union u u;
> printf("%ld\n", test(&u.x, &u.y, &u));
> }
>
> https://godbolt.org/z/a9drezEza
>
next prev parent reply other threads:[~2021-07-27 8:02 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-25 11:58 Uecker, Martin
2021-07-27 8:02 ` Richard Biener [this message]
2021-07-27 8:05 ` Richard Biener
2021-07-27 12:08 ` Richard Biener
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