From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 19177 invoked by alias); 13 Sep 2006 00:47:28 -0000 Received: (qmail 19169 invoked by uid 22791); 13 Sep 2006 00:47:28 -0000 X-Spam-Check-By: sourceware.org Received: from nile.gnat.com (HELO nile.gnat.com) (205.232.38.5) by sourceware.org (qpsmtpd/0.31) with ESMTP; Wed, 13 Sep 2006 00:47:23 +0000 Received: from localhost (localhost [127.0.0.1]) by filtered-nile.gnat.com (Postfix) with ESMTP id 84D2348CE0B for ; Tue, 12 Sep 2006 20:47:21 -0400 (EDT) Received: from nile.gnat.com ([127.0.0.1]) by localhost (nile.gnat.com [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 05999-01-5 for ; Tue, 12 Sep 2006 20:47:21 -0400 (EDT) Received: from takamaka.act-europe.fr (unknown [70.71.0.212]) by nile.gnat.com (Postfix) with ESMTP id 1AF0048CBD6 for ; Tue, 12 Sep 2006 20:47:21 -0400 (EDT) Received: by takamaka.act-europe.fr (Postfix, from userid 507) id 7059147F00; Tue, 12 Sep 2006 17:47:20 -0700 (PDT) Date: Wed, 13 Sep 2006 00:47:00 -0000 From: Joel Brobecker To: gdb@sources.redhat.com Subject: Re: (linux/threads) Interesting side-effect of "auto-solib-add 0" Message-ID: <20060913004720.GG24293@adacore.com> References: <20060913002712.GF24293@adacore.com> <20060913003347.GA24280@nevyn.them.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060913003347.GA24280@nevyn.them.org> User-Agent: Mutt/1.4i Mailing-List: contact gdb-help@sourceware.org; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sourceware.org X-SW-Source: 2006-09/txt/msg00067.txt.bz2 > You've missed the pertinent fact here. We're not waiting for > libpthread.so to be loaded just for kicks! The only way libthread_db > can operate is by querying back through GDB for the locations of > symbols in the thread library. If we don't load that objfile, then > it can't initialize. It's really strange. I put traces everywhere inside linux-thread-db so that if there was any callbacks called during the detection, I would see them. As you can see, I'm not very familiar with how this library works. Do you know where the callbacks are in the debugger code? I've been trying to find a document that explains how the pthread_db library works, is there one? > > The only difference I can see between the two runs is that symbols > > are read in one case, and not read in the other case. Is libthread_db.so > > dependent on having the symbol table being loaded or something of that > > sort? > > Yes. Don't load libpthread, won't get threads. Sounds fair enough to me. Eli, everyone, Would it be something worth documenting somewhere in the manual? I could probably write a small paragraph somewhere after the description of the auto-solib-add setting. Thanks! -- Joel