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From: "lin1.hu at intel dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/114700] Front-end optimization generates wrong code
 with -ftrapv.
Date: Fri, 12 Apr 2024 02:47:59 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114700

--- Comment #3 from lin1.hu at intel dot com ---
(In reply to lin1.hu from comment #2)
> (In reply to Andrew Pinski from comment #1)
> > Gcc's trapv is known not always to work correctly.
> >=20
> > Try -fsanitize=3Dundefined instead.

Thanks, it solves the problem to some extent. But c is eliminated, I think c
- y may cause signed overflow.

https://godbolt.org/z/Wbzx5Edsj=