From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 7173 invoked by alias); 23 Sep 2013 23:20:12 -0000 Mailing-List: contact gcc-help-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-help-owner@gcc.gnu.org Received: (qmail 7161 invoked by uid 89); 23 Sep 2013 23:20:12 -0000 Received: from mail-la0-f43.google.com (HELO mail-la0-f43.google.com) (209.85.215.43) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES128-SHA encrypted) ESMTPS; Mon, 23 Sep 2013 23:20:12 +0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.4 required=5.0 tests=AWL,BAYES_00,FREEMAIL_FROM,NO_RELAYS autolearn=ham version=3.3.2 X-HELO: mail-la0-f43.google.com Received: by mail-la0-f43.google.com with SMTP id ep20so2992260lab.2 for ; Mon, 23 Sep 2013 16:20:07 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.152.8.12 with SMTP id n12mr22294861laa.10.1379978407863; Mon, 23 Sep 2013 16:20:07 -0700 (PDT) Received: by 10.112.101.7 with HTTP; Mon, 23 Sep 2013 16:20:07 -0700 (PDT) In-Reply-To: <20130923184314.ada65e1d.jklowden@schemamania.org> References: <20130921164609.GC3086@a.lan> <20130921174229.GD3086@a.lan> <20130923000355.fa2a964c.jklowden@schemamania.org> <20130923114717.1033f2b8.jklowden@schemamania.org> <20130923184314.ada65e1d.jklowden@schemamania.org> Date: Mon, 23 Sep 2013 23:20:00 -0000 Message-ID: Subject: Re: how to make gcc warn about arithmetic signed overflow From: Jonathan Wakely To: "James K. Lowden" Cc: gcc-help Content-Type: text/plain; charset=ISO-8859-1 X-IsSubscribed: yes X-SW-Source: 2013-09/txt/msg00166.txt.bz2 On 23 September 2013 23:43, James K. Lowden wrote: > On Mon, 23 Sep 2013 22:50:09 +0100 > The compiler's job is to convert C ++ logic into machine logic, and to > reject anything it cannot do so with absolute assurance. If I could > wish something for C++14, it would be a 90% reduction in UB > descriptions. Let's define the behavior and be done with it. By > removing ambiguity, maybe the definition the language would become > readable again. There's a study group looking into that, see the note on SG12 at http://isocpp.org/std/the-committee Getting involved with the group would be a lot more effective than wishing :-)