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From: "amonakov at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/111210] Wrong code at -Os on x86_64-linux-gnu since
 r12-4849-gf19791565d7
Date: Mon, 28 Aug 2023 12:55:57 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D111210

--- Comment #4 from Alexander Monakov <amonakov at gcc dot gnu.org> ---
The testcase is small enough to notice the issue by inspection.

Note that you get the "expected" answer with -fno-strict-aliasing, and as
explained in https://gcc.gnu.org/bugs/ it is one of the things you should c=
heck
when submitting a bugreport:

Before reporting that GCC compiles your code incorrectly, compile it with g=
cc
-Wall -Wextra and see whether this shows anything wrong with your code.
Similarly, if compiling with -fno-strict-aliasing -fwrapv
-fno-aggressive-loop-optimizations makes a difference, or if compiling with
-fsanitize=3Dundefined produces any run-time errors, then your code is prob=
ably
not correct.=