From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 21927 invoked by alias); 15 Jan 2015 07:50:38 -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 21913 invoked by uid 48); 15 Jan 2015 07:50:32 -0000 From: "chengniansun at gmail dot com" To: gcc-bugs@gcc.gnu.org Subject: [Bug c/64610] New: No -Wbool-compare warning on "(0 != a) >= 0" Date: Thu, 15 Jan 2015 07:50:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: c X-Bugzilla-Version: 5.0 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: chengniansun at gmail dot com X-Bugzilla-Status: UNCONFIRMED 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: bug_id short_desc product version bug_status bug_severity priority component assigned_to reporter Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-SW-Source: 2015-01/txt/msg01288.txt.bz2 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64610 Bug ID: 64610 Summary: No -Wbool-compare warning on "(0 != a) >= 0" Product: gcc Version: 5.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c Assignee: unassigned at gcc dot gnu.org Reporter: chengniansun at gmail dot com There is no warning on the expression "(0 != a) >= 0". I think the cause of this bug is different from the one I reported just now (PR64609). $: cat s.c int a; void fn1() { ((0 != a) >= 0); } $: $: gcc-trunk -Wbool-compare -c s.c $: $: clang-trunk -Wno-unused-value -c s.c s.c:2:24: warning: comparison of constant 0 with boolean expression is always true [-Wtautological-constant-out-of-range-compare] void fn1() { ((0 != a) >= 0); } ~~~~~~~~ ^ ~ 1 warning generated. $: $: