From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 18076 invoked by alias); 21 Sep 2005 20:37:13 -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 18015 invoked by uid 22791); 21 Sep 2005 20:37:03 -0000 Received: from sj-iport-3-in.cisco.com (HELO sj-iport-3.cisco.com) (171.71.176.72) by sourceware.org (qpsmtpd/0.30-dev) with ESMTP; Wed, 21 Sep 2005 20:37:03 +0000 Received: from sj-core-1.cisco.com ([171.71.177.237]) by sj-iport-3.cisco.com with ESMTP; 21 Sep 2005 13:37:01 -0700 X-IronPort-AV: i="3.97,132,1125903600"; d="scan'208"; a="344155668:sNHT32065380" Received: from xbh-sjc-221.amer.cisco.com (xbh-sjc-221.cisco.com [128.107.191.63]) by sj-core-1.cisco.com (8.12.10/8.12.6) with ESMTP id j8LKaR5M009460; Wed, 21 Sep 2005 13:36:59 -0700 (PDT) Received: from xfe-sjc-211.amer.cisco.com ([171.70.151.174]) by xbh-sjc-221.amer.cisco.com with Microsoft SMTPSVC(6.0.3790.211); Wed, 21 Sep 2005 13:36:57 -0700 Received: from [128.107.165.235] ([128.107.165.235]) by xfe-sjc-211.amer.cisco.com with Microsoft SMTPSVC(6.0.3790.211); Wed, 21 Sep 2005 13:36:56 -0700 Message-ID: <4331C468.3080204@cisco.com> Date: Wed, 21 Sep 2005 20:37:00 -0000 From: Michael Snyder User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.3) Gecko/20040929 MIME-Version: 1.0 To: Ian Lance Taylor CC: Eli Zaretskii , gdb@sources.redhat.com, shebs@apple.com Subject: Re: Using reverse execution References: <43309387.4020504@cisco.com> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-SW-Source: 2005-09/txt/msg00163.txt.bz2 Ian Lance Taylor wrote: > Eli Zaretskii writes: > > >>>Cc: gdb@sources.redhat.com, shebs@apple.com >>>From: Ian Lance Taylor >>>Date: 20 Sep 2005 16:13:55 -0700 >>> >>>There is probably some cool use for which tracepoints are the >>>obvious right answer, but I don't know what it is. >> >>In native debugging, tracepoints would be very useful to debug a >>real-time program, or, more generally, a program where timing issues >>are crucial to its correct operation. With such programs, normal GDB >>usage disrupts the program operation and might even cause the program >>to fail in ways that are unrelated to the bug you are looking for. > > > I get that that is the idea, it's just that I wouldn't tackle that > problem that way. I would put a logging framework in the program > itself. That's how I've debugged this sort of issue in the past, and > the logging framework generally pays off for itself over time. That's what tracepoint debugging is, Ian -- it's a re-usable logging framework. It just frees you up from having to write that logging code over and over into different projects, and recompile your project whenever you want to log something different. Well, that and a way-cool interactive data review and presentation mode. ;-) But let's not highjack this thread to talk about tracepoints, unles it's to compare their use and utility to reverse execution. Michael