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From: "xry111 at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/114700] Front-end optimization generates wrong code
 with -fsanitize=undefined
Date: Fri, 12 Apr 2024 06:33:25 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114700

Xi Ruoyao <xry111 at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|Front-end optimization      |Front-end optimization
                   |generates wrong code with   |generates wrong code with
                   |-ftrapv.                    |-fsanitize=3Dundefined
                 CC|                            |xry111 at gcc dot gnu.org

--- Comment #10 from Xi Ruoyao <xry111 at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #9)
> That that GCC doesn't promise that -ftrapv preserves all overflows and
> traps, it merely guarantees that all overflows that actually happen trap.=
=20
> So GCC is fine to contract some expressions where the overall number of
> overflows can only
> decrease.
>=20
> That's not a bug with -ftrapv.
>=20
> It is considered a bug with -fsanitize=3Dundefined though.

So modifying the subject.=