From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 2461 invoked by alias); 8 Jul 2009 12:53:43 -0000 Received: (qmail 2451 invoked by uid 22791); 8 Jul 2009 12:53:42 -0000 X-SWARE-Spam-Status: No, hits=-2.5 required=5.0 tests=AWL,BAYES_00 X-Spam-Check-By: sourceware.org Received: from NaN.false.org (HELO nan.false.org) (208.75.86.248) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 08 Jul 2009 12:53:35 +0000 Received: from nan.false.org (localhost [127.0.0.1]) by nan.false.org (Postfix) with ESMTP id DCB5D10576; Wed, 8 Jul 2009 12:53:32 +0000 (GMT) Received: from caradoc.them.org (209.195.188.212.nauticom.net [209.195.188.212]) by nan.false.org (Postfix) with ESMTP id 6EF6310554; Wed, 8 Jul 2009 12:53:32 +0000 (GMT) Received: from drow by caradoc.them.org with local (Exim 4.69) (envelope-from ) id 1MOWeQ-0007xO-U7; Wed, 08 Jul 2009 08:53:30 -0400 Date: Wed, 08 Jul 2009 12:53:00 -0000 From: Daniel Jacobowitz To: Mark Kettenis Cc: gdb-patches@sourceware.org, matz@suse.de Subject: Re: RFC: %ebp-based backtrace patch Message-ID: <20090708125330.GA29881@caradoc.them.org> Mail-Followup-To: Mark Kettenis , gdb-patches@sourceware.org, matz@suse.de References: <20090706183316.GA26074@caradoc.them.org> <200907062157.n66LvSVF007634@brahms.sibelius.xs4all.nl> <20090707130040.GA11040@caradoc.them.org> <200907080901.n6891GVC029930@brahms.sibelius.xs4all.nl> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200907080901.n6891GVC029930@brahms.sibelius.xs4all.nl> User-Agent: Mutt/1.5.20 (2009-06-14) X-IsSubscribed: yes Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org X-SW-Source: 2009-07/txt/msg00233.txt.bz2 On Wed, Jul 08, 2009 at 11:01:16AM +0200, Mark Kettenis wrote: > Before comitting this diff, I ran the testsuite, and noticed a > regression. The problem is that if you do a function call through a > null-function-pointer or an otherwise corrupt function pointer, and > get a SIGSEGV, the backtrace no longer shows the frame that did the > function call. > > Until we come up with a way to fix this issue, I'm not going to commit > the diff. Hmm. if (target_read_memory (pc, buf, 1)) ? That's how a similar issue is handled on ARM, in arm_stub_unwind_sniffer. -- Daniel Jacobowitz CodeSourcery