From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 16530 invoked by alias); 21 Jul 2009 18:09:17 -0000 Received: (qmail 16521 invoked by uid 22791); 21 Jul 2009 18:09:17 -0000 X-SWARE-Spam-Status: No, hits=-2.2 required=5.0 tests=AWL,BAYES_00,J_CHICKENPOX_21 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; Tue, 21 Jul 2009 18:09:10 +0000 Received: from nan.false.org (localhost [127.0.0.1]) by nan.false.org (Postfix) with ESMTP id 6109510B04; Tue, 21 Jul 2009 18:09:08 +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 47C3310A63; Tue, 21 Jul 2009 18:09:08 +0000 (GMT) Received: from drow by caradoc.them.org with local (Exim 4.69) (envelope-from ) id 1MTJlz-000367-Lt; Tue, 21 Jul 2009 14:09:07 -0400 Date: Tue, 21 Jul 2009 18:15:00 -0000 From: Daniel Jacobowitz To: Thinker Li Cc: gdb-patches@sourceware.org Subject: Re: Get backtrace at PLT and stepi into PLT Message-ID: <20090721180907.GB11667@caradoc.them.org> Mail-Followup-To: Thinker Li , gdb-patches@sourceware.org References: <20090720120722.GA28313@caradoc.them.org> <19045.11906.492610.388479@bibi.branda.to> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <19045.11906.492610.388479@bibi.branda.to> User-Agent: Mutt/1.5.20 (2009-06-14) 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: 2009-07/txt/msg00519.txt.bz2 On Tue, Jul 21, 2009 at 10:57:06AM +0800, Thinker Li wrote: > You can not do backtrace when you stop at PLT with GDB. > arm_stub_unwind_sniffer create a frame with NORMAL_FRAME type for > PLT. But, when we do backtrace, get_prev_frame() will check if > this frame inside_entry_func. Since we can not found any symbol for > PLT, it:s func address is 0, and entry_point_address() is also 0 if > symfile_objfile is NULL (no main symbol table). It makes problem on > backtracing. Thanks, that's much clearer. That's where the bug is. An unknown function address should not be inside_entry_func. -- Daniel Jacobowitz CodeSourcery