From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from esa4.mentor.iphmx.com (esa4.mentor.iphmx.com [68.232.137.252]) by sourceware.org (Postfix) with ESMTPS id 8D62D3857366 for ; Wed, 27 Jul 2022 16:12:05 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 8D62D3857366 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=codesourcery.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=mentor.com X-IronPort-AV: E=Sophos;i="5.93,195,1654588800"; d="scan'208";a="80412388" Received: from orw-gwy-01-in.mentorg.com ([192.94.38.165]) by esa4.mentor.iphmx.com with ESMTP; 27 Jul 2022 08:12:01 -0800 IronPort-SDR: /G2s8luYWT3Agqcc/ZwwgRfS+nMVNOpLQajOl2cHSn6crRgcFb6ATDhlbNnpImYuXKnTvU1pyk O+I2ctHkhqHzQ61rRn6lsV0bLltn1FZF2JBE/zzk1fJoPGQQ4uA3jPS0C8Il7wmjlhg6VMFjHY pR6pVleH7wyINMccwy95DcWGh0orl5zy8u9IPNgOgvJ3RJ/qKya+WqLHIQQTI+bbUQJvkDCrW8 56S/dac9nRD1NE12QDrernYTg6jCAB0K6IM1pAZMnDbYIWcRyxTDbSksAMgxvh9bXBomkeu+Ta 9Ys= Date: Wed, 27 Jul 2022 16:11:50 +0000 From: Joseph Myers X-X-Sender: jsm28@digraph.polyomino.org.uk To: Noah Goldstein CC: Subject: Re: [PATCH v2] NEWS: Add entry for x86-64 ISA level build In-Reply-To: <20220727121023.2146666-1-goldstein.w.n@gmail.com> Message-ID: References: <20220727065841.2140573-1-goldstein.w.n@gmail.com> <20220727121023.2146666-1-goldstein.w.n@gmail.com> User-Agent: Alpine 2.22 (DEB 394 2020-01-19) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" X-Originating-IP: [137.202.0.90] X-ClientProxiedBy: SVR-IES-MBX-08.mgc.mentorg.com (139.181.222.8) To svr-ies-mbx-10.mgc.mentorg.com (139.181.222.10) X-Spam-Status: No, score=-3111.4 required=5.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, KAM_DMARC_STATUS, SPF_HELO_PASS, SPF_PASS, TXREP, URIBL_BLACK autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 27 Jul 2022 16:12:06 -0000 On Wed, 27 Jul 2022, Noah Goldstein via Libc-alpha wrote: > +* Support building x86-64 with multiple ISA levels has been added. > + Higher ISA levels will use better optimized functions in the dynamic > + loader and non-multiarch build as well as reduce the size of libc.so. I don't think "with multiple ISA levels" is very meaningful to users. How is "with multiple ISA levels" different from the multi-arch feature that's been present for many years - I think it could easily be read as a description of that longstanding existing feature? You need a description that makes clear to users who aren't following glibc development what the actual new feature is (i.e. that if you build with a compiler that defaults to a newer ISA level such as -march=x86-64-v2, the resulting libc will use corresponding optimized implementations and omit the versions only relevant on older processors, if I'm understanding the feature correctly). -- Joseph S. Myers joseph@codesourcery.com