From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 30509 invoked by alias); 2 May 2013 08:01:44 -0000 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 Received: (qmail 30457 invoked by uid 48); 2 May 2013 08:01:40 -0000 From: "rguenth at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug tree-optimization/57124] 254.gap@spec2000 got miscompare after r198413 Date: Thu, 02 May 2013 08:01:00 -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-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: rguenth at gcc dot gnu.org X-Bugzilla-Status: ASSIGNED X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: law at redhat dot com X-Bugzilla-Target-Milestone: --- X-Bugzilla-Changed-Fields: 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" MIME-Version: 1.0 X-SW-Source: 2013-05/txt/msg00061.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57124 --- Comment #3 from Richard Biener 2013-05-02 08:01:39 UTC --- At least the reduced testcase contains undefined signed integer overflow. It multiplies 65531 by 65536 here: x3 = x2 * 65536; it's still "miscompiled" with -fno-strict-overflow though, a QOI issue (it works correctly with -fwrapv). The docs trying to point out the difference between -fno-strict-overflow and -fwrapv are especially poor (ISTR strongly objecting the notion of -f[no-]strict-overflow ...)