From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 5232 invoked by alias); 20 Feb 2013 22:04:31 -0000 Received: (qmail 5214 invoked by uid 22791); 20 Feb 2013 22:04:30 -0000 X-SWARE-Spam-Status: No, hits=-3.0 required=5.0 tests=AWL,BAYES_00,KHOP_THREADED X-Spam-Check-By: sourceware.org Received: from toast.topped-with-meat.com (HELO topped-with-meat.com) (204.197.218.159) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 20 Feb 2013 22:04:21 +0000 Received: by topped-with-meat.com (Postfix, from userid 5281) id 25AA22C0A7; Wed, 20 Feb 2013 14:04:21 -0800 (PST) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit From: Roland McGrath To: Torvald Riegel CC: libc-ports@sourceware.org, libc-alpha@sourceware.org Subject: Re: PI mutex support for pthread_cond_* now in nptl In-Reply-To: Torvald Riegel's message of Wednesday, 20 February 2013 21:25:26 +0100 <1361391926.581.1774.camel@triegel.csb> References: <20130218105637.GJ32163@spoyarek.pnq.redhat.com> <5123AB55.2070100@twiddle.net> <1361304381.581.80.camel@triegel.csb> <1361379598.19573.167.camel@spokane1.rchland.ibm.com> <1361391926.581.1774.camel@triegel.csb> Message-Id: <20130220220421.25AA22C0A7@topped-with-meat.com> Date: Wed, 20 Feb 2013 22:04:00 -0000 X-CMAE-Score: 0 X-CMAE-Analysis: v=2.1 cv=LYSvtFvi c=1 sm=1 tr=0 a=WkljmVdYkabdwxfqvArNOQ==:117 a=14OXPxybAAAA:8 a=tabI2Y8SnEIA:10 a=Z6MIti7PxpgA:10 a=kj9zAlcOel0A:10 a=hOe2yjtxAAAA:8 a=7ueD6xqgVFQA:10 a=oMDdHdszQLSiWzJrk_UA:9 a=CjuIK1q_8ugA:10 X-IsSubscribed: yes Mailing-List: contact libc-ports-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: libc-ports-owner@sourceware.org X-SW-Source: 2013-02/txt/msg00057.txt.bz2 At least the x86 assembly versions were written because the code produced by GCC at the time was drastically worse. But that was long ago. We now mandate compiling with GCC 4.3 or newer and recommend 4.6 or newer, so it merits examining the code produced by those compilers and reconsidering the judgments of the past. But we will be conservative and not drop any hand-written assembly unless recent compilers at -O2 are demonstrated to produce code at least as good. (Perhaps the reasonable standard is something like at least as good from 4.6 -O3 and not a whole lot worse from 4.3 -O2.) As time goes on, we can of course examine then-common compilers and reconsider these judgments. As of now, even 4.7 is not common yet. Thanks, Roland