From owner-freebsd-questions@FreeBSD.ORG Wed Jun 20 09:46:49 2012 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id EF5E8106564A for ; Wed, 20 Jun 2012 09:46:48 +0000 (UTC) (envelope-from c.kworr@gmail.com) Received: from mail-bk0-f54.google.com (mail-bk0-f54.google.com [209.85.214.54]) by mx1.freebsd.org (Postfix) with ESMTP id 672478FC0C for ; Wed, 20 Jun 2012 09:46:48 +0000 (UTC) Received: by bkvi18 with SMTP id i18so7475529bkv.13 for ; Wed, 20 Jun 2012 02:46:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; bh=3VfV877hXltDkSXq7gLlZoKJgAt86Uchn7O4zbf6eJc=; b=MhjeIV33hY3dTMZCLdXPoQuO/WOmqInLyerzhE1su8skgjtasomzhvO/qtXsOIVz3A 9WimArKk+Pxq8X9GkTDiZKxR0/8mDyLKuL8iAJKx4/w7Ee3cm2nOL4sLyYmOEVqePbMq fTq1Bnsm7r6OluSJyU70tJjQQudHzGAmLk5ZGE1qSIfZd7kK2JDmsH6xyyq7CHqd6+rm Y644zaAm7E34RGbsgFvUtY7l7c1OuCWr6w3LrIBl+SYmjRkG1peAzuzSoSn8D7vW7Aqi 9x/bosreMh5ojBZ7nylELQ/K6siqCxYhqkIBKfnVWQWJlNCg1gkN/GSbf+MY0e00PB8f zVVg== Received: by 10.204.151.130 with SMTP id c2mr9956082bkw.125.1340185606579; Wed, 20 Jun 2012 02:46:46 -0700 (PDT) Received: from green.tandem.local (utwig.xim.bz. [91.216.237.46]) by mx.google.com with ESMTPS id 9sm26841466bku.9.2012.06.20.02.46.44 (version=SSLv3 cipher=OTHER); Wed, 20 Jun 2012 02:46:45 -0700 (PDT) Message-ID: <4FE19BFC.7030304@gmail.com> Date: Wed, 20 Jun 2012 12:46:36 +0300 From: Volodymyr Kostyrko User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:12.0) Gecko/20120605 Firefox/12.0 SeaMonkey/2.9.1 MIME-Version: 1.0 To: Wojciech Puchar References: <402199FE-380B-41B6-866B-7D5D66C457D5@lpthe.jussieu.fr> <854D02B1-CA89-4F5E-8773-DB05F2868D74@lpthe.jussieu.fr> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Adam Vande More , Michel Talon , Fred Morcos , freebsd-questions@freebsd.org Subject: Re: CLANG vs GCC tests of fortran/f2c program X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 20 Jun 2012 09:46:49 -0000 Wojciech Puchar wrote: >> 5. clang/llvm is more modular than gcc, although there are plans for >> gcc to become as modular, it will take time. > > Doesn't matter how it is written, but how it performs. That's a hard one. I remember an error in gcc loop optimizer which makes gcc produce SSE2 opcodes for pre-SSE2 athlon chips. Due to gcc internal design such errors are often seen and almost never patched as you should have eternal knowledge of gcc code. gcc's bugtraq is just a cemetery. Opposing to this ones most fixes to clang touch minimal source lines and minimal set of files. > Same should be used for clang. AS LONG as it is not better it should not > be imported into base system or worse - used as default. And why you think it's not better then gcc? With gcc I can result in code that will hang locking some parts of system forever, yet with clang the code will break predictably yielding a core and a point on where the debugging should start. That was long ago and I can't correctly remember the PR's are I noted this but that was long ago and helped me to debug ZFS issues a lot. The code that runs faster is not the best one. The code that is predictable and runs as fast as possible is. -- Sphinx of black quartz judge my vow.