From owner-freebsd-current Wed Feb 26 12:45:41 2003 Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 5388737B401 for ; Wed, 26 Feb 2003 12:45:40 -0800 (PST) Received: from grassmarket.ucs.ed.ac.uk (grassmarket.ucs.ed.ac.uk [129.215.166.64]) by mx1.FreeBSD.org (Postfix) with ESMTP id 35A6443F3F for ; Wed, 26 Feb 2003 12:45:38 -0800 (PST) (envelope-from bruce@cran.org.uk) Received: from fourtytwo.brucec.backnet (12266209.resnet.ed.ac.uk [10.6.0.100] (may be forged)) by grassmarket.ucs.ed.ac.uk (8.11.6/8.11.6) with ESMTP id h1QKiwh29712; Wed, 26 Feb 2003 20:45:14 GMT Received: from fourtytwo.brucec.backnet (localhost.fourtytwo.brucec.backnet [127.0.0.1]) by fourtytwo.brucec.backnet (8.12.6/8.12.6) with ESMTP id h1QKiub1032183; Wed, 26 Feb 2003 20:44:56 GMT (envelope-from bruce@fourtytwo.brucec.backnet) Received: (from bruce@localhost) by fourtytwo.brucec.backnet (8.12.6/8.12.6/Submit) id h1QKiuAO032182; Wed, 26 Feb 2003 20:44:56 GMT Date: Wed, 26 Feb 2003 20:44:56 +0000 From: Bruce Cran To: Fred Souza Cc: current@freebsd.org Subject: Re: -O2 considered harmful Message-ID: <20030226204456.GA4513@fourtytwo.brucec.backnet> References: <20030226113815.W5357@znfgre.tberna.bet> <20030226200635.GA1368@torment.storming.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20030226200635.GA1368@torment.storming.org> User-Agent: Mutt/1.5.3i Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Wed, Feb 26, 2003 at 05:06:35PM -0300, Fred Souza wrote: > > I was recently a participant in a thread in another forum where all sorts > > of people, including a well respected gcc developer, said categorically > > that the latest (stock) gcc produces correct code with -O2 in all cases on > > ia32. If it doesn't, the gcc folks would like a bug report. > > I use -O3 -mmmx -m3dnow -march=k6-2 on nearly everything (things that > break with that many optimization, such as XFree86-4-libraries, I > "downgrade" to the highest optimization possible - usually -O2), and > I'm not noticing any bad impacts because of it. > > And by "nearly everything" I even meant the kernel (yes, I can respect > if anyone screams "NUTZ!@!" ;-) > Is it just me, or does mozilla break when things are compiled with -march=athlon-xp? I'm not sure what happens, but mozilla starts to load, a window flashes up briefly before mozilla quits. Running dbg on it says that it segfaults in WindowGetHeight() or some such function. When I recompile _everything_ back using -O -march=pentiumpro it works again. I'm sure I've compiled it for athlon-xp before on 5.0-RELEASE, has something changed to break it? Bruce Cran To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message