From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 13264 invoked by alias); 4 Aug 2010 20:57:58 -0000 Received: (qmail 13251 invoked by uid 22791); 4 Aug 2010 20:57:57 -0000 X-SWARE-Spam-Status: No, hits=-2.1 required=5.0 tests=AWL,BAYES_00,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from mail3.caviumnetworks.com (HELO mail3.caviumnetworks.com) (12.108.191.235) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 04 Aug 2010 20:57:47 +0000 Received: from caexch01.caveonetworks.com (Not Verified[192.168.16.9]) by mail3.caviumnetworks.com with MailMarshal (v6,7,2,8378) id ; Wed, 04 Aug 2010 13:58:14 -0700 Received: from caexch01.caveonetworks.com ([192.168.16.9]) by caexch01.caveonetworks.com with Microsoft SMTPSVC(6.0.3790.4675); Wed, 4 Aug 2010 13:57:45 -0700 Received: from dd1.caveonetworks.com ([12.108.191.236]) by caexch01.caveonetworks.com over TLS secured channel with Microsoft SMTPSVC(6.0.3790.4675); Wed, 4 Aug 2010 13:57:45 -0700 Message-ID: <4C59D449.3020702@caviumnetworks.com> Date: Wed, 04 Aug 2010 20:57:00 -0000 From: David Daney User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.9) Gecko/20100430 Fedora/3.0.4-2.fc12 Thunderbird/3.0.4 MIME-Version: 1.0 To: Andi Kleen CC: "H.J. Lu" , Paul Pluzhnikov , gcc-patches@gcc.gnu.org Subject: Re: PATCH: Turn on -fomit-frame-pointer by default for 32bit Linux/x86 References: <87vd7qcdtx.fsf@basil.nowhere.org> In-Reply-To: <87vd7qcdtx.fsf@basil.nowhere.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org X-SW-Source: 2010-08/txt/msg00369.txt.bz2 On 08/04/2010 01:39 PM, Andi Kleen wrote: > "H.J. Lu" writes: > >> I am not sure about single handler. For malloc, are you referring to > > In Linux the kernel provides unwind information for the signal > handler. I just tested it and it works here with a frame pointer > less 32bit executable using gdb. Not that I doubt your claim, but the ability of gdb to unwind signal frames is not proof of the existence of kernel unwind information. gdb can often generate a backtrace (even through signal frames) in the absence of any debugging meta-data. David Daney