From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 21366 invoked by alias); 23 Jun 2009 18:25:16 -0000 Received: (qmail 21338 invoked by uid 22791); 23 Jun 2009 18:25:15 -0000 X-SWARE-Spam-Status: No, hits=-1.6 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_LOW,RCVD_NUMERIC_HELO,SPF_HELO_PASS,SPF_PASS X-Spam-Check-By: sourceware.org Received: from main.gmane.org (HELO ciao.gmane.org) (80.91.229.2) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Tue, 23 Jun 2009 18:25:07 +0000 Received: from root by ciao.gmane.org with local (Exim 4.43) id 1MJAg3-0007DE-V0 for gdb@sources.redhat.com; Tue, 23 Jun 2009 18:25:03 +0000 Received: from 69.34.67.62 ([69.34.67.62]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Tue, 23 Jun 2009 18:25:03 +0000 Received: from grant.b.edwards by 69.34.67.62 with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Tue, 23 Jun 2009 18:25:03 +0000 To: gdb@sources.redhat.com From: Grant Edwards Subject: Re: Troubleshooting broken gdbserver/remote-target Date: Tue, 23 Jun 2009 18:25:00 -0000 Message-ID: References: <8ac60eac0906230959k7d89636av6edd36d8d25b7457@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit User-Agent: slrn/pre0.9.9-102 (Linux) 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: 2009-06/txt/msg00222.txt.bz2 On 2009-06-23, Grant Edwards wrote: > On 2009-06-23, Paul Pluzhnikov wrote: > >>> What would cause gdb to miss out on the fact that >>> /lib/libuClibc-0.9.30.1.so is mapped? >>> >>> Where does gdb get mapping info? >> >> I believe the code GDB should be using on Linux is in solib-svr4.c >> >> Gdb looks for _r_debug symbol and DT_DEBUG Elf32_Dyn entry to >> find the 'struct r_debug', which contains a linked list of >> loaded shared libraries, and traverses that list. > > Thanks for the hint. When I have a chance I'll see if I can > figure out what's wrong. I presume gdb is looking for those > symbols in the ELF executable file? > >> My guess: either GDB is not finding _r_debug, or (more likely) >> is not traversing the list correctly. > > I found other reports that 6.8 doesn't work for ARM targets, > but 6.7.1 does. I switched from 6.8 to 6.7.1, and that fixed > the problem. > > Now to see if that fixed the problems with thread support > as well... Indeed it does! Multithreaded debugging using gdbserver on an ARM9 target works fine with 6.7.1, but it with 6.8 you get SIG32 and a variety of other problems. -- Grant Edwards grante Yow! ... I want FORTY-TWO at TRYNEL FLOATATION SYSTEMS visi.com installed within SIX AND A HALF HOURS!!!