From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 24110 invoked by alias); 30 Jan 2008 16:42:21 -0000 Received: (qmail 24101 invoked by uid 22791); 30 Jan 2008 16:42:20 -0000 X-Spam-Check-By: sourceware.org Received: from shell4.BAYAREA.NET (HELO shell4.bayarea.net) (209.128.82.1) by sourceware.org (qpsmtpd/0.31) with ESMTP; Wed, 30 Jan 2008 16:42:02 +0000 Received: (qmail 22719 invoked from network); 30 Jan 2008 08:42:00 -0800 Received: from 209-128-106-254.bayarea.net (HELO ?192.168.20.7?) (209.128.106.254) by shell4.bayarea.net with SMTP; 30 Jan 2008 08:42:00 -0800 Message-ID: <47A0A8D8.7090508@eagercon.com> Date: Wed, 30 Jan 2008 16:42:00 -0000 From: Michael Eager User-Agent: Thunderbird 1.5.0.9 (X11/20070102) MIME-Version: 1.0 To: gdb@sourceware.org Subject: Finding ld.so dynamic loader Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit 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: 2008-01/txt/msg00333.txt.bz2 I've been reading through solib_open() in solib.c and the way that the code searches for the dynamic loader doesn't make sense to me, especially when using gdbserver to debug a program on a remote system. Perhaps someone can explain to me why it is correct. solib_open() is called by enable_break() with the name of the dynamic loader, say, "/lib/ld.so.1". The comments at the top of solib_open() say: 125 * If there is a solib_absolute_prefix and path is absolute: 126 * Search for solib_absolute_prefix/path. 127 * else 128 * Look for it literally (unmodified). 129 * Look in SOLIB_SEARCH_PATH. 130 * If available, use target defined search function. 131 * If solib_absolute_prefix is NOT set, perform the following two searches: 132 * Look in inferior's $PATH. 133 * Look in inferior's $LD_LIBRARY_PATH. If solib_absolute_prefix is empty (true for almost all targets) and /lib/ld.so.1 exists on the host system, this will be opened in preference to either one specified on the SOLIB_SEARCH_PATH or using a target search path. This seems incorrect. The dynamic loader on the host system may not be the same as on the target system, and in the case of cross development, may not even have the same architecture. Shouldn't the search using the unmodified name be the last choice, not the first? Can someone explain to me how gdb is supposed to find the correct ld.so or why I'm looking at this incorrectly? -- Michael Eager eager@eagercon.com 1960 Park Blvd., Palo Alto, CA 94306 650-325-8077