From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 7338 invoked by alias); 13 Jun 2011 16:43:38 -0000 Received: (qmail 7325 invoked by uid 22791); 13 Jun 2011 16:43:36 -0000 X-SWARE-Spam-Status: No, hits=-6.9 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_HI,SPF_HELO_PASS,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Mon, 13 Jun 2011 16:43:23 +0000 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id p5DGhNVK024344 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Mon, 13 Jun 2011 12:43:23 -0400 Received: from ns3.rdu.redhat.com (ns3.rdu.redhat.com [10.11.255.199]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id p5DGhME7018627; Mon, 13 Jun 2011 12:43:22 -0400 Received: from opsy.redhat.com (ovpn01.gateway.prod.ext.phx2.redhat.com [10.5.9.1]) by ns3.rdu.redhat.com (8.13.8/8.13.8) with ESMTP id p5DGhLRM021497; Mon, 13 Jun 2011 12:43:22 -0400 Received: by opsy.redhat.com (Postfix, from userid 500) id 805A4378232; Mon, 13 Jun 2011 10:43:21 -0600 (MDT) From: Tom Tromey To: Jan Kratochvil Cc: Mark Kettenis , gdb-patches@sourceware.org Subject: Re: [RFC] i386 PLT stub unwinder References: <201106131555.p5DFtucc019690@glazunov.sibelius.xs4all.nl> <20110613161402.GB18588@host1.jankratochvil.net> Date: Mon, 13 Jun 2011 16:43:00 -0000 In-Reply-To: <20110613161402.GB18588@host1.jankratochvil.net> (Jan Kratochvil's message of "Mon, 13 Jun 2011 18:14:02 +0200") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii 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: 2011-06/txt/msg00170.txt.bz2 >>>>> "Jan" == Jan Kratochvil writes: Jan> On Mon, 13 Jun 2011 17:55:56 +0200, Mark Kettenis wrote: >> Jan's mail about DWARF CFI for PLT stubs prompted me to write an >> undinder for the PLT stubs as defined by the i386 ABI. With this >> change I can step through the PLT stubs and always have a proper >> backtrace. Jan> I do not think GDB is the right place to fix it, it should be fixed Jan> by proper .eh_Frame as this problem affects all the tools trying to Jan> unwind such as also oprofile, systemtap etc. I agree, but I think also doing it in GDB is harmless, at least provided that the new unwinder is only applied when the PLT stubs are missing the needed info. That way, when ld is fixed, GDB will automatically start doing the right thing. Tom