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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/109968] False Warning stringop-overread at
 -O2
Date: Fri, 26 May 2023 06:08:38 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D109968

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2023-05-26
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1

--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
 f1(&s->s2.b);

 err =3D write1( 1, (const void *)&(s->s2), 6);

we CSE &s->s2 as &s->s2.b which derails ptr-query.  -Wstringop-overread has=
 to
happen before we finalize object sizes and set optimizers lose.  Instead we
emit this diagnostic in the very late warn_access pass.=