From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261596AbVFERnm (ORCPT ); Sun, 5 Jun 2005 13:43:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261595AbVFERnm (ORCPT ); Sun, 5 Jun 2005 13:43:42 -0400 Received: from emailhub.stusta.mhn.de ([141.84.69.5]:13835 "HELO mailout.stusta.mhn.de") by vger.kernel.org with SMTP id S261599AbVFERn1 (ORCPT ); Sun, 5 Jun 2005 13:43:27 -0400 Date: Sun, 5 Jun 2005 19:43:22 +0200 From: Adrian Bunk To: Nick Warne Cc: linux-kernel@vger.kernel.org Subject: Re: CPU type .config <-> i386/Makefile question[s] Message-ID: <20050605174322.GF4992@stusta.de> References: <200506051458.50307.nick@linicks.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200506051458.50307.nick@linicks.net> User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Jun 05, 2005 at 02:58:50PM +0100, Nick Warne wrote: > Hello all, Hi Nick, > I am still a n00b here learning, so by all means tell me to get lost if what I > am about to say is total bollocks... > > I was just running through building the new 2.4.31 kernel on my Quake2 box, > with looking at building this time with a few optimisations. >... > Is there a specific reason why the flags aren't -march=pentium2, pentiumpro > etc? the specific reason is that kernel 2.4 is in a maintainance mode and such changes are not considered being worth the risk of breaking anything anywhere with any of the supported gcc versions. In kernel 2.6, this is already handled the way you expect it. > Also I notice that if I changed the top level Makefile to include my specific > CPU, then the i386/Makefile adds += -march=i686 to the build lines AFTER > CFLAGS~ thus the second one will take precedence (I guess) anyway, and the > -march CFLAG changes are basically over-ridden? Users are not expected to manually set any CFLAGS. It might work in your case, but unless you _really_ know what you are doing you always risk some breakage. > Regards, > > Nick cu Adrian -- "Is there not promise of rain?" Ling Tan asked suddenly out of the darkness. There had been need of rain for many days. "Only a promise," Lao Er said. Pearl S. Buck - Dragon Seed