From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 31430 invoked by alias); 17 Jan 2012 16:25:44 -0000 Received: (qmail 31399 invoked by uid 22791); 17 Jan 2012 16:25:41 -0000 X-SWARE-Spam-Status: No, hits=-1.9 required=5.0 tests=BAYES_00,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from r-finger.com (HELO r-finger.com) (178.79.160.5) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Tue, 17 Jan 2012 16:25:20 +0000 Received: from [192.168.0.2] (host86-132-174-224.range86-132.btcentralplus.com [86.132.174.224]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by r-finger.com (Postfix) with ESMTPSA id B54EB9C0A for ; Tue, 17 Jan 2012 16:25:19 +0000 (GMT) Message-ID: <4F15A0EA.4070008@r-finger.com> Date: Tue, 17 Jan 2012 16:25:00 -0000 From: Tomas Frydrych User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.21) Gecko/20110831 Icedove/3.1.13 MIME-Version: 1.0 To: ecos-devel@ecos.sourceware.org Subject: Re: Gnutools: consideration for upgrade to GCC 4.6 References: <4F106345.4080902@siva.com.mk> <4F15412B.9040601@r-finger.com> <4F159D3C.1060108@meduna.org> In-Reply-To: <4F159D3C.1060108@meduna.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact ecos-devel-help@ecos.sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: ecos-devel-owner@ecos.sourceware.org X-SW-Source: 2012-01/txt/msg00029.txt.bz2 Hi, On 17/01/12 16:09, Stanislav Meduna wrote: > On 17.01.2012 10:36, Tomas Frydrych wrote: >> Some of the more recent gccs were not producing usable binaries on some >> platforms (including arm) with the -Os option. I do not know if this is >> the case with 4.6.2, and I don't think ecos uses -Os by default, but it >> is probably worth checking whether this works (and at least documenting >> somewhere if it does not). > > Do you happen to have more details on this - versions, flags used, > example to reproduce...? > > http://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html says > > -Os enables all -O2 optimizations that do not typically increase > code size. It also performs further optimizations designed > to reduce code size. > > it would be good to know whether the problems come from -O2 (which > would be a major problem) or from these further optimizations. It was known to be present in gcc 4.5.1, and it was not effecting the -O2 option, only -Os. The openembedded/yoctoproject guys run into it building u-boot, and it was mentioned yesterday on the poky mailing list, https://lists.yoctoproject.org/pipermail/poky/2012-January/007472.html. Tomas