From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 32055 invoked by alias); 31 Oct 2011 10:18:54 -0000 Received: (qmail 32044 invoked by uid 22791); 31 Oct 2011 10:18:53 -0000 X-SWARE-Spam-Status: No, hits=-2.9 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00 X-Spam-Check-By: sourceware.org Received: from localhost (HELO gcc.gnu.org) (127.0.0.1) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Mon, 31 Oct 2011 10:18:38 +0000 From: "manu at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug c/50922] infinite loop when optimized Date: Mon, 31 Oct 2011 10:18:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: c X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: manu at gcc dot gnu.org X-Bugzilla-Status: RESOLVED X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Changed-Fields: CC Message-ID: In-Reply-To: References: X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org X-SW-Source: 2011-10/txt/msg03195.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D50922 Manuel L=C3=B3pez-Ib=C3=A1=C3=B1ez changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |manu at gcc dot gnu.org --- Comment #5 from Manuel L=C3=B3pez-Ib=C3=A1=C3=B1ez 2011-10-31 10:18:29 UTC --- (In reply to comment #4) > Am 30.10.11 20:14, schrieb pinskia at gcc dot gnu.org: > > --- Comment #3 from Andrew Pinski 2011-10-= 30 19:14:49 UTC --- > > Signed integer overflow is undefined so this is invalid. > > > If this is true, shouldnt the compiler give an error message or at least > a warning? > But I think incrementing is always well defined, even when overflowing. > And in the example the result after occuring the overflow is not > used anyway. http://gcc.gnu.org/wiki/FAQ#signed_overflow