From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 685BD3858C66; Thu, 12 Jan 2023 07:33:28 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 685BD3858C66 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1673508808; bh=Xjc8/f9osYyYjQx+nqPcQY8p4UoH6o6FzFNrerpIfiE=; h=From:To:Subject:Date:In-Reply-To:References:From; b=LQ3aLU1PrXhsexVg693EWL093YlenAqps+YsCrNQJFZuJW/Nq34qfCVc6rpJLCyTI yz9rjDD6iifWMM6GCLHOUx2hellYO/NYH7murU21GgDWb1Se3QkSST8tREzlk7eTKy QUnBno2EBXf4fLh68Hp+fsrza1hWPTI4G2KJntgM= From: "rguenth at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug tree-optimization/107838] spurious "may be used uninitialized" warning on variable initialized at the first iteration of a loop Date: Thu, 12 Jan 2023 07:33:27 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: tree-optimization X-Bugzilla-Version: 13.0 X-Bugzilla-Keywords: diagnostic X-Bugzilla-Severity: normal X-Bugzilla-Who: rguenth at gcc dot gnu.org X-Bugzilla-Status: ASSIGNED X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: rguenth at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: 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 List-Id: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D107838 --- Comment #4 from Richard Biener --- comment#3 is a slightly different issue in that we do not have the guarding condition obviously true here, instead what we'd need to prove is that r_8 is always initialized because the first loop iteration initializes it. Maybe it's somehow possible to code that into the uninit analysis machinery, I'd have to think about this.=