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From: "vincent-gcc at vinc17 dot net" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c/93432] variable is used uninitialized, but gcc shows no warning
Date: Fri, 25 Feb 2022 15:45:01 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D93432

Vincent Lef=C3=A8vre <vincent-gcc at vinc17 dot net> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |vincent-gcc at vinc17 dot =
net

--- Comment #6 from Vincent Lef=C3=A8vre <vincent-gcc at vinc17 dot net> ---
(In reply to Manuel L=C3=B3pez-Ib=C3=A1=C3=B1ez from comment #4)
> It warns in gcc 10.1. It may good idea to add this one as a testcase, sin=
ce
> it seems it got fixed without noticing.

Has this really been fixed, or does it work now just by chance?

This looks like PR18501, where the concerned variable is initialized only at
one place in the loop. Here, "z =3D 1" is followed by "z=3Dz+1", so that th=
is is
equivalent to "z =3D 2". But if in the code, I do this change, the warning
disappears (tested with gcc-12 (Debian 12-20220222-1) 12.0.1 20220222
(experimental) [master r12-7325-g2f59f067610] and -O1, -O2, -O3).=