From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 17629 invoked by alias); 21 May 2008 19:44:20 -0000 Received: (qmail 17621 invoked by uid 22791); 21 May 2008 19:44:19 -0000 X-Spam-Check-By: sourceware.org Received: from NaN.false.org (HELO nan.false.org) (208.75.86.248) by sourceware.org (qpsmtpd/0.31) with ESMTP; Wed, 21 May 2008 19:44:00 +0000 Received: from nan.false.org (localhost [127.0.0.1]) by nan.false.org (Postfix) with ESMTP id 856DD983FF; Wed, 21 May 2008 19:43:58 +0000 (GMT) Received: from caradoc.them.org (22.svnf5.xdsl.nauticom.net [209.195.183.55]) by nan.false.org (Postfix) with ESMTP id 6F2CA98371; Wed, 21 May 2008 19:43:58 +0000 (GMT) Received: from drow by caradoc.them.org with local (Exim 4.69) (envelope-from ) id 1JyuE9-0000q0-4E; Wed, 21 May 2008 15:43:57 -0400 Date: Thu, 22 May 2008 03:14:00 -0000 From: Daniel Jacobowitz To: Ulrich Weigand Cc: Pedro Alves , gdb-patches@sourceware.org Subject: Re: [patch] Re: longjmp handling vs. glibc LD_POINTER_GUARD problems Message-ID: <20080521194357.GA2934@caradoc.them.org> Mail-Followup-To: Ulrich Weigand , Pedro Alves , gdb-patches@sourceware.org References: <200805202353.47984.pedro@codesourcery.com> <200805211920.m4LJKJXS016101@d12av02.megacenter.de.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200805211920.m4LJKJXS016101@d12av02.megacenter.de.ibm.com> User-Agent: Mutt/1.5.17 (2008-05-11) 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: 2008-05/txt/msg00649.txt.bz2 On Wed, May 21, 2008 at 09:20:19PM +0200, Ulrich Weigand wrote: > Another issue with your patch is the use of frame_id_inner ... I'd rather > get rid of this function instead of adding new uses, because this really > requires that it is possible to compare two stack (frame) addresses > along a linear order. This breaks for me in multi-architecture scenarios, > but even on existing targets it may not always work OK (e.g. if signal > handlers run on a different frame, or if the code uses some sort of > user-level threading or coroutine library ...). Maybe instead of > comparing frame_ids, it would be better to check whether or not a > frame with the given ID still exists in the current backtrace? Let's be careful, if doing that, that we don't search too far up the stack chain. Infinite stacks are a not uncommon failure mode when something's gone wrong in GDB... -- Daniel Jacobowitz CodeSourcery