On Mon, Apr 4, 2022 at 1:52 PM Robin Dapp via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> Hi,
>
> in gcc.dg/Wuse-after-free-2.c we try to detect a use-after-free. On
> s390 the test's while loop is converted into a rawmemchr builtin making
> it impossible to determine that the pointers *p and *q are related.
>
> Therefore, disable the tree loop distribute patterns pass on s390 for
> this test.
>
> OK for trunk?
>
> Regards
> Robin
>
> gcc/testsuite/ChangeLog:
>
> * gcc.dg/Wuse-after-free-2.c:
> Add -fno-tree-loop-distribute-patterns for s390*.
>
>
> ---
> diff --git a/gcc/testsuite/gcc.dg/Wuse-after-free-2.c
> b/gcc/testsuite/gcc.dg/Wuse-after-free-2.c
> index 9f7ed4529f0..3a8f690e9f8 100644
> --- a/gcc/testsuite/gcc.dg/Wuse-after-free-2.c
> +++ b/gcc/testsuite/gcc.dg/Wuse-after-free-2.c
> @@ -1,6 +1,8 @@
> /* PR middle-end/104232 - spurious -Wuse-after-free after conditional free
> { dg-do compile }
> - { dg-options "-O2 -Wall" } */
> + { dg-options "-O2 -Wall" }
> + { dg-additional-options "-fno-tree-loop-distribute-patterns" {
> target { s390*-*-* } } }
Please add the option unconditional and add a comment wrt rawmemchr
OK with that change.
> + */
>
> void free (void*);
>
> --
> 2.35.1
>
