From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 23302 invoked by alias); 4 Mar 2010 02:13:42 -0000 Received: (qmail 23209 invoked by uid 22791); 4 Mar 2010 02:13:41 -0000 X-SWARE-Spam-Status: No, hits=-2.5 required=5.0 tests=AWL,BAYES_00 X-Spam-Check-By: sourceware.org Received: from mail.codesourcery.com (HELO mail.codesourcery.com) (38.113.113.100) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Thu, 04 Mar 2010 02:13:38 +0000 Received: (qmail 31656 invoked from network); 4 Mar 2010 02:13:36 -0000 Received: from unknown (HELO orlando.localnet) (pedro@127.0.0.2) by mail.codesourcery.com with ESMTPA; 4 Mar 2010 02:13:36 -0000 From: Pedro Alves To: Michael Snyder Subject: Re: Watching expressions that don't involve memory (e.g., watch $regfoo) Date: Thu, 04 Mar 2010 02:13:00 -0000 User-Agent: KMail/1.12.2 (Linux/2.6.31-19-generic; KDE/4.3.2; x86_64; ; ) Cc: "gdb-patches@sourceware.org" References: <201003040156.44957.pedro@codesourcery.com> <4B8F155E.8050209@vmware.com> In-Reply-To: <4B8F155E.8050209@vmware.com> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201003040213.19438.pedro@codesourcery.com> 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: 2010-03/txt/msg00146.txt.bz2 On Thursday 04 March 2010 02:05:18, Michael Snyder wrote: > I think watching registers, or expressions involving registers > (such as $sp > 0x10000000) could be incredibly useful. Yeah, that works. (top-gdb) p $rsp $1 = (void *) 0x7fffffffe040 (top-gdb) watch $rsp < 0x7fffffffe040 Watchpoint 4: $rsp < 0x7fffffffe040 (top-gdb) c Continuing. Watchpoint 4: $rsp < 0x7fffffffe040 Old value = 0 New value = 1 0x0000000000454fd8 in memset@plt () (top-gdb) bt #0 0x0000000000454fd8 in memset@plt () #1 0x0000000000456659 in main (argc=1, argv=0x7fffffffe158) at ../../src/gdb/gdb.c:28 (top-gdb) > Expressions on a varobj sound useful to watch too. What do you mean by varobj here? If that's something that you can "(gdb) print", it should work too. It sounds like it opens pathway for some crazy watching :-) > One question; what will happen if I watch a constant? The watchpoint never triggers, as is today. -- Pedro Alves