From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 11814 invoked by alias); 29 Nov 2010 11:12:54 -0000 Received: (qmail 11797 invoked by uid 22791); 29 Nov 2010 11:12:53 -0000 X-SWARE-Spam-Status: No, hits=-2.0 required=5.0 tests=AWL,BAYES_00,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from gate.crashing.org (HELO gate.crashing.org) (63.228.1.57) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Mon, 29 Nov 2010 11:12:45 +0000 Received: from gate.crashing.org (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.13.8) with ESMTP id oATBC1Ir008024; Mon, 29 Nov 2010 05:12:01 -0600 Received: (from apache@localhost) by gate.crashing.org (8.14.1/8.14.1/Submit) id oATBC1BV008023; Mon, 29 Nov 2010 12:12:01 +0100 Received: from 94.211.195.167 (SquirrelMail authenticated user segher) by gate.crashing.org with HTTP; Mon, 29 Nov 2010 12:12:01 +0100 (CET) Message-ID: <52488.94.211.195.167.1291029121.squirrel@gate.crashing.org> In-Reply-To: <4CF37603.5080301@de.ibm.com> References: <20101129081619.GD5218@cr0.nay.redhat.com> <4CF37603.5080301@de.ibm.com> Date: Mon, 29 Nov 2010 11:12:00 -0000 Subject: Re: [PATCH] Built kernel without -O2 option From: "Segher Boessenkool" To: "Christian Borntraeger" Cc: =?iso-8859-1?Q?Am=E9rico_Wang?= , "Hui Zhu" , linux-kernel@vger.kernel.org, gdb@sourceware.org, hellogcc@freelists.org, linux-kbuild@vger.kernel.org User-Agent: SquirrelMail/1.4.10a-1.fc6 MIME-Version: 1.0 Content-Type: text/plain;charset=iso-8859-1 Content-Transfer-Encoding: 8bit Mailing-List: contact gdb-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sourceware.org X-SW-Source: 2010-11/txt/msg00116.txt.bz2 > In essence -O2 just tells gcc to activate a list of optimizations > gcc -Q -O2 --help=optimizers > tells you what. Not quite; see http://gcc.gnu.org/wiki/FAQ#optimization-options . Segher