From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 108842 invoked by alias); 6 Oct 2015 10:54:06 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Received: (qmail 108223 invoked by uid 89); 6 Oct 2015 10:54:05 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.8 required=5.0 tests=AWL,BAYES_00,SPF_HELO_PASS,T_RP_MATCHES_RCVD autolearn=ham version=3.3.2 X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES256-GCM-SHA384 encrypted) ESMTPS; Tue, 06 Oct 2015 10:54:04 +0000 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (Postfix) with ESMTPS id 315D4A10A6; Tue, 6 Oct 2015 10:54:03 +0000 (UTC) Received: from localhost (ovpn-116-138.ams2.redhat.com [10.36.116.138]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id t96As2j0016237; Tue, 6 Oct 2015 06:54:02 -0400 Date: Tue, 06 Oct 2015 10:54:00 -0000 From: Jonathan Wakely To: gcc-patches@gcc.gnu.org Cc: Gerald Pfeifer , Joseph Myers , Sandra Loosemore Subject: [wwwdocs] Suggest UBsan in https://gcc.gnu.org/bugs/ Message-ID: <20151006105401.GP12094@redhat.com> MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="nM4qzG6nHdnn/sXd" Content-Disposition: inline X-Clacks-Overhead: GNU Terry Pratchett User-Agent: Mutt/1.5.23 (2014-03-12) X-SW-Source: 2015-10/txt/msg00523.txt.bz2 --nM4qzG6nHdnn/sXd Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline Content-length: 213 For many non-bugs UBsan is at least as likely to reveal it as -fno-strict-aliasing -fwrapv -fno-aggressive-loop-optimizations so we should tell people to try that before wasting time in Bugzilla. OK for wwwdocs? --nM4qzG6nHdnn/sXd Content-Type: text/x-patch; charset=us-ascii Content-Disposition: attachment; filename="patch.txt" Content-length: 873 Index: htdocs/bugs/index.html =================================================================== RCS file: /cvs/gcc/wwwdocs/htdocs/bugs/index.html,v retrieving revision 1.116 diff -u -r1.116 index.html --- htdocs/bugs/index.html 5 Jul 2014 21:52:32 -0000 1.116 +++ htdocs/bugs/index.html 6 Oct 2015 10:50:32 -0000 @@ -50,7 +50,11 @@ with gcc -Wall -Wextra and see whether this shows anything wrong with your code. Similarly, if compiling with -fno-strict-aliasing -fwrapv -fno-aggressive-loop-optimizations -makes a difference, your code probably is not correct.

+makes a difference, your code probably is not correct. +If compiling with -fsanitize=undefined is supported by your +version of GCC and produces any run-time errors your code is definitely +not correct. +

Summarized bug reporting instructions

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