From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from gate.crashing.org ([63.228.1.57] ident=[U2FsdGVkX19/MEAtMehLW2o82UH9oH3jxe79n+tc2Mc=]) by linuxtogo.org with esmtp (Exim 4.72) (envelope-from ) id 1Qw4kR-0005OG-0x for openembedded-core@lists.openembedded.org; Wed, 24 Aug 2011 06:07:27 +0200 Received: from [IPv6:::1] (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.13.8) with ESMTP id p7O42b0o000742; Tue, 23 Aug 2011 23:02:37 -0500 Mime-Version: 1.0 (Apple Message framework v1084) From: Kumar Gala In-Reply-To: <1314150303.5939.70.camel@rex> Date: Tue, 23 Aug 2011 23:02:37 -0500 Message-Id: <7D14B031-9782-4012-B31C-A46BE077672F@kernel.crashing.org> References: <0597F428-97F2-461F-804B-FE793E911BD4@kernel.crashing.org> <1314150303.5939.70.camel@rex> To: Patches and discussions about the oe-core layer , Richard Purdie X-Mailer: Apple Mail (2.1084) Subject: Re: why do we poison -Os? X-BeenThere: openembedded-core@lists.openembedded.org X-Mailman-Version: 2.1.11 Precedence: list Reply-To: Patches and discussions about the oe-core layer List-Id: Patches and discussions about the oe-core layer List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 24 Aug 2011 04:07:27 -0000 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable On Aug 23, 2011, at 8:45 PM, Richard Purdie wrote: > On Tue, 2011-08-23 at 20:32 -0500, Kumar Gala wrote: >> If tinylogin is the only issue why modify/patch gcc? I see we have >> meta/recipes-core/tinylogin/tinylogin-1.4/use_O2_option.patch to deal >> with this? >>=20 >> Not allowing -Os at all, which is our current situation on PPC is >> problematic. So trying to see if this issue is really limited to gcc >> 4.5 or not. How can I reproduce it with current poky.git? >=20 > We were seeing problems when makefiles were putting -Os into compiler > flags without our knowledge. In some cases -Os was silently corrupting > binaries. We therefore ended up adding the poison so if anything was > using the option we knew to generate buggy code, we'd know about it. So, I'm trying to figure out if it was just tinylogin or more that had = issues. > If we know gcc to be safe using that option we can drop the patch and > users can enable it where it makes sense to them. I still don't like > makefiles changing compiler optimisations from under us though. Last I > heard, -Os was still very badly supported and not recommended by the = gcc > community. That's a different issue altogether. I think its bad that we dont allow = -Os at all which is what I'm trying address and the fact that its pretty = necessary to build u-boot because it has size limitations. - k=