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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug c/108720] INT_MIN * -1 is incorrect Date: Wed, 08 Feb 2023 16:47:51 +0000 [thread overview] Message-ID: <bug-108720-4-3iDySXGpFv@http.gcc.gnu.org/bugzilla/> (raw) In-Reply-To: <bug-108720-4@http.gcc.gnu.org/bugzilla/> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108720 --- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> --- int x = # 6 "err_file.c" 3 4 (-0x7fffffff - 1) # 6 "err_file.c" ; int y = x * -1; x*-1 invokes undefined behavior because signed integer overflow is undefined. So anything can happen after undefined behavior including but not limited to inconsistent results. You can detect signed integer overflow at run time with -fsanitize=undefined.
next prev parent reply other threads:[~2023-02-08 16:47 UTC|newest] Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top 2023-02-08 16:41 [Bug c/108720] New: " amk7r at mtmail dot mtsu.edu 2023-02-08 16:43 ` [Bug c/108720] " amk7r at mtmail dot mtsu.edu 2023-02-08 16:45 ` jakub at gcc dot gnu.org 2023-02-08 16:47 ` pinskia at gcc dot gnu.org [this message] 2023-02-08 16:49 ` pinskia at gcc dot gnu.org
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