From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 15684 invoked by alias); 12 Jun 2007 11:22:11 -0000 Received: (qmail 15672 invoked by uid 22791); 12 Jun 2007 11:22:10 -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; Tue, 12 Jun 2007 11:22:08 +0000 Received: from nan.false.org (localhost [127.0.0.1]) by nan.false.org (Postfix) with ESMTP id 8023E982F1; Tue, 12 Jun 2007 11:22:06 +0000 (GMT) Received: from caradoc.them.org (22.svnf5.xdsl.nauticom.net [209.195.183.55]) by nan.false.org (Postfix) with ESMTP id 5AE90982DC; Tue, 12 Jun 2007 11:22:06 +0000 (GMT) Received: from drow by caradoc.them.org with local (Exim 4.67) (envelope-from ) id 1Hy4S5-0007ka-6I; Tue, 12 Jun 2007 07:22:21 -0400 Date: Tue, 12 Jun 2007 11:22:00 -0000 From: Daniel Jacobowitz To: Robert Norton Cc: gdb@sourceware.org Subject: Re: Target Dependent Backtrace Termination Message-ID: <20070612112221.GC29495@caradoc.them.org> Mail-Followup-To: Robert Norton , gdb@sourceware.org References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.15 (2007-04-09) X-IsSubscribed: yes 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: 2007-06/txt/msg00092.txt.bz2 On Tue, Jun 12, 2007 at 02:23:11AM -0700, Robert Norton wrote: > to go one too far! Looking at some other ports it seems that the > solution is to return the null frame id for the outermost frame thus > causing get_prev_frame_1 to return null and terminating the backtrace. Right. > But this means that the outermost frame doesn't haven't a valid frame > id! Won't this cause problems? Am I missing something rather > fundamental? Also right. We've been talking on and off about changing this, so that an unwinder can indicate "this is marked as the last frame" separately from "I don't know what this frame's ID is". If we manage to do that, I hope we can require all frames to have a valid ID. No one's done it yet, though. -- Daniel Jacobowitz CodeSourcery