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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug middle-end/98503] [11/12 regression] -Warray-bounds false
 positive with global variables at -O2 since r11-3306-g3f9a497d1b0dd9da
Date: Wed, 23 Mar 2022 08:31:54 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D98503

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |INVALID

--- Comment #18 from Richard Biener <rguenth at gcc dot gnu.org> ---
So at the point we diagnose we see the following IL for cont_dump:

<bb 2> [local count: 1073741824]:
__mptr_5 =3D MEM[(struct ref *)&head].list.n;
goto <bb 8>; [100.00%]

that's because the testcase has static 'last_dumped' which means it is NULL
and we start restart_dump with

        if (!last)
            last =3D get_initial_step();

which does

static inline struct ref *get_initial_step()
{
    return container_of(&head, struct ref, list);
}

that means next_step will do the bad access of 'head' using the struct ref
type.=