From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 29914 invoked by alias); 25 Jan 2007 22:03:37 -0000 Received: (qmail 29899 invoked by uid 22791); 25 Jan 2007 22:03:37 -0000 X-Spam-Check-By: sourceware.org Received: from mail-out4.apple.com (HELO mail-out4.apple.com) (17.254.13.23) by sourceware.org (qpsmtpd/0.31) with ESMTP; Thu, 25 Jan 2007 22:03:31 +0000 Received: from relay5.apple.com (a17-128-113-35.apple.com [17.128.113.35]) by mail-out4.apple.com (8.13.8/8.13.8) with ESMTP id l0PM1OPt013849; Thu, 25 Jan 2007 14:01:24 -0800 (PST) Received: from relay5.apple.com (unknown [127.0.0.1]) by relay5.apple.com (Symantec Mail Security) with ESMTP id 9F4CB29C002; Thu, 25 Jan 2007 14:01:24 -0800 (PST) X-AuditID: 11807123-a2358bb0000039f2-52-45b928b4cf27 Received: from [17.201.24.155] (unknown [17.201.24.155]) by relay5.apple.com (Apple SCV relay) with ESMTP id 7E9F630400B; Thu, 25 Jan 2007 14:01:24 -0800 (PST) Cc: richard.guenther@gmail.com, ebotcazou@adacore.com, gcc-patches@gcc.gnu.org, mark@codesourcery.com Message-Id: <6FECE966-A8EB-4AC9-8677-48354D50A73B@apple.com> From: Mike Stump To: Richard Kenner In-Reply-To: <10701251144.AA24290@vlsi1.ultra.nyu.edu> Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes X-Smtp-Server: relay.apple.com Mime-Version: 1.0 (Apple Message framework v863) Subject: Re: [PATCH] Tree SRA and atomicity/volatility Content-Transfer-Encoding: 7bit Date: Thu, 25 Jan 2007 22:03:00 -0000 References: <200701061422.39157.ebotcazou@adacore.com> <45B63E9B.9090909@codesourcery.com> <84fc9c000701230924g37ed4f42vca8d7ae0c1ef6e52@mail.gmail.com> <45B6643C.6000800@codesourcery.com> <84fc9c000701231257u7fb1f10rdd3255be8aa69686@mail.gmail.com> <10701240137.AA23316@vlsi1.ultra.nyu.edu> <84fc9c000701240127x2fe9492bq355cd35260e7b55e@mail.gmail.com> <10701241307.AA01425@vlsi1.ultra.nyu.edu> <84fc9c000701240533p217a2735i8e42634e07029df7@mail.gmail.com> <45B7A5E8.3080102@codesourcery.com> <84fc9c000701250138s26cd7932oc00a139c7c321898@mail.gmail.com> <10701251144.AA24290@vlsi1.ultra.nyu.edu> X-Mailer: Apple Mail (2.863) X-IsSubscribed: yes 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 X-SW-Source: 2007-01/txt/msg02120.txt.bz2 On Jan 25, 2007, at 3:44 AM, Richard Kenner wrote: > But we still can't try to express it in any semantically-meaningful > way. :-( I disagree fundamentally with this notion. gcc, being an implementation, is free to talk about opcodes produced or not on i686, if it wants. It can talk about signal handlers, exceptions, delay slots... It can talk about chipset bus interlocks on various processors. I think many people probably posses enough knowledge of what volatile means to attempt a definition. They might not get a few of the corner cases right, but, those can be hammered out over time. Someone on the C++ committee wanted to do this and nail things down, but, they didn't have the background and the deep understanding required, so we shot it down. Better to have less than a language spec that is just wrong.