From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 21368 invoked by alias); 10 Jun 2009 17:13:40 -0000 Received: (qmail 21360 invoked by uid 22791); 10 Jun 2009 17:13:40 -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, 10 Jun 2009 17:13:32 +0000 Received: from nan.false.org (localhost [127.0.0.1]) by nan.false.org (Postfix) with ESMTP id 81CCF10738; Wed, 10 Jun 2009 17:13:29 +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 2624510728; Wed, 10 Jun 2009 17:13:29 +0000 (GMT) Received: from drow by caradoc.them.org with local (Exim 4.69) (envelope-from ) id 1MERMe-00006A-2D; Wed, 10 Jun 2009 13:13:28 -0400 Date: Wed, 10 Jun 2009 17:13:00 -0000 From: Daniel Jacobowitz To: Pedro Alves Cc: gdb-patches@sourceware.org, tromey@redhat.com, Joel Brobecker Subject: Re: RFC: next/finish/etc -vs- exceptions Message-ID: <20090610171328.GA32661@caradoc.them.org> Mail-Followup-To: Pedro Alves , gdb-patches@sourceware.org, tromey@redhat.com, Joel Brobecker References: <20090610161204.GB25703@adacore.com> <200906101806.31977.pedro@codesourcery.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200906101806.31977.pedro@codesourcery.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: 2009-06/txt/msg00266.txt.bz2 On Wed, Jun 10, 2009 at 06:06:31PM +0100, Pedro Alves wrote: > I assume that exceptions have a property that raw longjmp doesn't, > which is what makes stepping over longjmp complicated --- they never > switch to alternate stacks? That was one reason why comparing > frame/stack pointers with inner_than kind of comparisions is > verboten (to know when the longjmp/exception is all inner to the > step/next and can be ignored, for example). That, and frames > crossing architectures, like on Cell. I did spot one such comparision > by a quick look at the patch, but I don't know if it OK to do so in > your case or not. I assume other people who know more about > frames and unwinders than me can provide better input there. :-) Not sure what you mean exactly, but exceptions can be thrown through signal handlers on many platforms; so yes, they might switch stack. They could go to any stack higher on the call frame. -- Daniel Jacobowitz CodeSourcery