From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 5E1223858400; Fri, 25 Feb 2022 15:45:02 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 5E1223858400 From: "vincent-gcc at vinc17 dot net" To: gcc-bugs@gcc.gnu.org Subject: [Bug c/93432] variable is used uninitialized, but gcc shows no warning Date: Fri, 25 Feb 2022 15:45:01 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: c X-Bugzilla-Version: 9.2.0 X-Bugzilla-Keywords: diagnostic, easyhack X-Bugzilla-Severity: normal X-Bugzilla-Who: vincent-gcc at vinc17 dot net X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: cc Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: gcc-bugs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-bugs mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 25 Feb 2022 15:45:02 -0000 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D93432 Vincent Lef=C3=A8vre changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |vincent-gcc at vinc17 dot = net --- Comment #6 from Vincent Lef=C3=A8vre --- (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).=