From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 27136 invoked by alias); 5 Apr 2004 19:13:53 -0000 Mailing-List: contact gdb-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sources.redhat.com Received: (qmail 27081 invoked from network); 5 Apr 2004 19:13:39 -0000 Received: from unknown (HELO mx1.redhat.com) (66.187.233.31) by sources.redhat.com with SMTP; 5 Apr 2004 19:13:39 -0000 Received: from int-mx1.corp.redhat.com (int-mx1.corp.redhat.com [172.16.52.254]) by mx1.redhat.com (8.12.10/8.12.10) with ESMTP id i35JDd5F009177 for ; Mon, 5 Apr 2004 15:13:39 -0400 Received: from localhost.redhat.com (to-dhcp51.toronto.redhat.com [172.16.14.151]) by int-mx1.corp.redhat.com (8.11.6/8.11.6) with ESMTP id i35JDdj14451; Mon, 5 Apr 2004 15:13:39 -0400 Received: from gnu.org (localhost [127.0.0.1]) by localhost.redhat.com (Postfix) with ESMTP id 81ACE2B9D; Mon, 5 Apr 2004 15:10:58 -0400 (EDT) Message-ID: <4071AF42.90401@gnu.org> Date: Mon, 05 Apr 2004 19:13:00 -0000 From: Andrew Cagney User-Agent: Mozilla/5.0 (X11; U; NetBSD macppc; en-GB; rv:1.4.1) Gecko/20040217 MIME-Version: 1.0 To: gdb@sources.redhat.com Subject: segv and function descriptors Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-SW-Source: 2004-04/txt/msg00028.txt.bz2 Hello, I'm trying to come up with a robust test for GDB backtracing through a NULL function pointer vis: segv_handler 0 main ABIs using function descriptors unfortunatly end up with the stack: segv_handler main This is because the call ((*)())0 turns into a data (the descriptor) access at 0 rather than a code access. Can anyone think of a way to detect a descriptor abi? If I know that, I can fudge a null descriptor and hence always cause the correct segv. Andrew