From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 3313 invoked by alias); 13 Dec 2006 21:46:01 -0000 Received: (qmail 3235 invoked by uid 22791); 13 Dec 2006 21:45:54 -0000 X-Spam-Check-By: sourceware.org Received: from nevyn.them.org (HELO nevyn.them.org) (66.93.172.17) by sourceware.org (qpsmtpd/0.31.1) with ESMTP; Wed, 13 Dec 2006 21:45:44 +0000 Received: from drow by nevyn.them.org with local (Exim 4.63) (envelope-from ) id 1Gubv2-0007YA-9u; Wed, 13 Dec 2006 16:45:40 -0500 Date: Wed, 13 Dec 2006 21:46:00 -0000 From: Daniel Jacobowitz To: Mark Kettenis Cc: Jan Kratochvil , gdb-patches@sourceware.org Subject: Re: [PATCH] Re: Unwinding CFI gcc practice of assumed `same value' regs Message-ID: <20061213214540.GA28965@nevyn.them.org> Mail-Followup-To: Mark Kettenis , Jan Kratochvil , gdb-patches@sourceware.org References: <20061211190300.GA4372@host0.dyn.jankratochvil.net> <20061211224022.AD76E1800E7@magilla.sf.frob.com> <20061212155233.GH29911@devserv.devel.redhat.com> <20061213204603.GA11741@host0.dyn.jankratochvil.net> <20061213210357.GA27039@nevyn.them.org> <23342.82.92.89.47.1166046052.squirrel@webmail.xs4all.nl> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <23342.82.92.89.47.1166046052.squirrel@webmail.xs4all.nl> User-Agent: Mutt/1.5.13 (2006-08-11) 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: 2006-12/txt/msg00181.txt.bz2 On Wed, Dec 13, 2006 at 10:40:52PM +0100, Mark Kettenis wrote: > It's a perfectly reasonable thing for the libgcc unwinder to do (just > as it is for us in GDB). But in a debugger I want to see that PC == 0 > if it is an abnormal backtrace termination. > > What really needs to be done is making the DWARF2 unwinder recognize the > condition and return a suitable frame id for that. Sorry, but I'm confused again :-( Do you mean making the DWARF2 unwinder decide that ra == 0 is a clean terminator? That seems like a bad thing to do if you want to ever show PC == 0 as abnormal termination; then it will do so only if the last frame left on the stack didn't have DWARF2 info. Or do you mean some other change to the unwinder? -- Daniel Jacobowitz CodeSourcery