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From: "glisse at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/94930] Failure to optimize out subvsi in
 expansion of __builtin_memcmp with 1 as the operand with -ftrapv
Date: Sun, 03 May 2020 14:45:35 +0000
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X-Bugzilla-Component: tree-optimization
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D94930

--- Comment #1 from Marc Glisse <glisse at gcc dot gnu.org> ---
AFAIK -ftrapv doesn't work very well and is kind of abandoned, in favor of
-fsanitize=3Dsigned-integer-overflow (possibly with
-fsanitize-undefined-trap-on-error), which does generate the code you expec=
t.=