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 4.50) id 1Eeiwt-0003Wv-Kb for garchives@archives.gentoo.org; Wed, 23 Nov 2005 00:57:24 +0000 Received: from robin.gentoo.org (localhost [127.0.0.1]) by robin.gentoo.org (8.13.5/8.13.5) with SMTP id jAN0u5Mq012398; Wed, 23 Nov 2005 00:56:05 GMT Received: from wproxy.gmail.com (wproxy.gmail.com [64.233.184.203]) by robin.gentoo.org (8.13.5/8.13.5) with ESMTP id jAN0q7Hh003025 for ; Wed, 23 Nov 2005 00:52:08 GMT Received: by wproxy.gmail.com with SMTP id 68so835317wri for ; Tue, 22 Nov 2005 16:52:07 -0800 (PST) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:sender:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=JSV7FGVxYdtQC2/sIMoExk48TdWNCz4A1pTSekj+RYNllckqczSaFJMA691/0OYg/2DdPVy2cYzGP9rizkM/frxz6puINfwhnpaWrdD7xJCufq8otevjvx8i7MOW7pt3ZL1P1eQHlJ5StaalcIIa9Tx0/df2BetexE/0lrwKs3s= Received: by 10.54.66.7 with SMTP id o7mr251199wra; Tue, 22 Nov 2005 16:52:07 -0800 (PST) Received: by 10.54.126.13 with HTTP; Tue, 22 Nov 2005 16:52:06 -0800 (PST) Message-ID: <7573e9640511221652i70df6190pe98d444430fad2d4@mail.gmail.com> Date: Tue, 22 Nov 2005 17:52:06 -0700 From: Richard Fish Sender: richard.j.fish@gmail.com To: gentoo-user@lists.gentoo.org Subject: Re: changing CHOST in stage3 (was : [gentoo-user] default stage3) In-Reply-To: <1132701374.10257.11.camel@sputnik886.ruz-net> Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Disposition: inline References: <4382B549.1020402@mid.email-server.info> <1132701374.10257.11.camel@sputnik886.ruz-net> Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by robin.gentoo.org id jAN0q7Hh003025 X-Archives-Salt: 2c00d2b7-c18f-4181-8b44-d7e9020040f6 X-Archives-Hash: 8cf0f519d1e62c0711db79c154f94f02 On 11/22/05, Matthias Langer wrote: > On Tue, 2005-11-22 at 17:11 -0500, Matthew Cline wrote: > > On 11/22/05, Alexander Skwar wrote: > > > > > > Why? What do you expect to gain? > > > > > > > The computer I am installing this on is an old Compaq laptop with a > > Cyrix MediaGX processor. Everything I have read suggests that this is > > equivalent to an i586. > > > > Am I wrong in thinking that the CHOST variable should reflect the kind > > of processor in the machine? Wouldn't leaving the CHOST at > > "i386-pc-linux-gnu" build unoptimized binaries? > > > > > > Matt > > > > I'm not an expert, but this is just copied and pasted from the gentoo > handbook: > > The CHOST variable declares the target build host for your system. This > variable should already be set to the correct value. Do not edit it as > that might break your system. If the CHOST variable does not look > correct to you, you might be using the wrong stage3 tarball. > > Cheers, Matthias AFAICT, CHOST is (mostly) used by portage for the "--host" argument to the autoconf scripts, which in turn uses it to determine the path for the tool chain. So having CHOST=i386-blah-blah means you are using the tool chain /usr/bin/i386-blah-blah-*. This is also the _default_ host that gcc will build code for. So without any -march/-mcpu/-mtune settings in CFLAGS, you will get i386 code. However, you can override that in CFLAGS, so that gcc produces i586 code by default (if that is what you want). AFAIK, there should be no difference in code produced by "i586-pc-linux-gnu-gcc" and "i386-pc-linux-gnu-gcc -march=i586". If there is, then things like distcc should be horribly broken. -Richard -- gentoo-user@gentoo.org mailing list