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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c/98503] [11 regression] -Warray-bounds false positive with
 global variables at -O2 since r11-3306-g3f9a497d1b0dd9da
Date: Tue, 05 Jan 2021 11:16:55 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D98503

--- Comment #8 from Richard Biener <rguenth at gcc dot gnu.org> ---
Note the example clearly violates C TBAA rules and the "optimization" of
eliding the data member(s) for 'head' are invalid.  It's not only about
diagnostics but about wrong-code generation waiting to happen (unless you u=
se
-fno-strict-aliasing).

If you access only the list head part then use a pointer to list for the
access.
Note I don't see the actual bogus access (the accesses seem to be guarded
with &curr->list !=3D &head) but the warning might be exposed by path isola=
ting
of actually unreachable code.=