From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lists.gentoo.org ([140.105.134.102] helo=robin.gentoo.org) by nuthatch.gentoo.org with esmtp (Exim 4.60) (envelope-from ) id 1GnH4Y-0004RW-Gz for garchives@archives.gentoo.org; Thu, 23 Nov 2006 16:05:11 +0000 Received: from robin.gentoo.org (localhost [127.0.0.1]) by robin.gentoo.org (8.13.8/8.13.8) with SMTP id kANG390B012803; Thu, 23 Nov 2006 16:03:09 GMT Received: from smtp2.nildram.co.uk (smtp2.nildram.co.uk [195.112.4.54] (may be forged)) by robin.gentoo.org (8.13.8/8.13.8) with ESMTP id kANG380H004786 for ; Thu, 23 Nov 2006 16:03:09 GMT Received: from wstn.prhnet (prh.gotadsl.co.uk [81.6.251.123]) by smtp2.nildram.co.uk (Postfix) with ESMTP id E8FFD2B53DD; Thu, 23 Nov 2006 16:03:05 +0000 (GMT) From: Peter Humphrey To: gentoo-amd64@lists.gentoo.org Subject: Re: [gentoo-amd64] Another package that doesn't like GCC 4 Date: Thu, 23 Nov 2006 16:03:08 +0000 User-Agent: KMail/1.9.5 References: <200611221628.33584.prh@gotadsl.co.uk> <200611231139.36213.prh@gotadsl.co.uk> <200611231358.40124.janjitse@gmail.com> In-Reply-To: <200611231358.40124.janjitse@gmail.com> Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-amd64@gentoo.org Reply-to: gentoo-amd64@lists.gentoo.org MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200611231603.08344.prh@gotadsl.co.uk> X-Archives-Salt: 38380e87-c1d5-4817-bb74-5e55ab6df2da X-Archives-Hash: 57276afeb4df036b48ce355122d48600 On Thursday 23 November 2006 12:58, Jan Jitse Venselaar wrote: > ... have you benchmarked in any way the effect of all these > optimizations on the programs you run? You basically do -Os and then turn > almost everything on which differs -O2 from -Os, negating the size > difference, plus some extra very experimental flags, which might increase > or decrease performance (sorry, but GCC works that way, extra > optimizations could actually be pessimizations), and probably break some > programs. You may have seen some discussion of compiler optimisations on this list, in which a set of flags have been offered and some people have played with them. I thought I'd have a go, and was reporting what I'd found. In light of what you say, I think I'll just go back to a simple set of flags (-march=k8 -Os -pipe) and leave it at that. And no, I hadn't noticed any performance improvement with all those flags - another good reason for reverting. Better, probably. Thanks for the advice. -- Rgds Peter -- gentoo-amd64@gentoo.org mailing list