From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 8109 invoked by alias); 12 Apr 2011 20:40:09 -0000 Received: (qmail 8098 invoked by uid 22791); 12 Apr 2011 20:40:09 -0000 X-SWARE-Spam-Status: No, hits=-6.9 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_HI,SPF_HELO_PASS,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Tue, 12 Apr 2011 20:40:02 +0000 Received: from int-mx12.intmail.prod.int.phx2.redhat.com (int-mx12.intmail.prod.int.phx2.redhat.com [10.5.11.25]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id p3CKdrEh012268 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Tue, 12 Apr 2011 16:39:53 -0400 Received: from ns3.rdu.redhat.com (ns3.rdu.redhat.com [10.11.255.199]) by int-mx12.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id p3CKdqqM031211; Tue, 12 Apr 2011 16:39:52 -0400 Received: from opsy.redhat.com (ovpn01.gateway.prod.ext.phx2.redhat.com [10.5.9.1]) by ns3.rdu.redhat.com (8.13.8/8.13.8) with ESMTP id p3CKdpWB022072; Tue, 12 Apr 2011 16:39:52 -0400 Received: by opsy.redhat.com (Postfix, from userid 500) id 91A883791BA; Tue, 12 Apr 2011 14:39:51 -0600 (MDT) From: Tom Tromey To: Pedro Alves Cc: gdb-patches@sourceware.org, Sergio Durigan Junior Subject: Re: [PATCH 3/6] Modify internalvar mechanism References: <201104121224.31901.pedro@codesourcery.com> Date: Tue, 12 Apr 2011 20:40:00 -0000 In-Reply-To: <201104121224.31901.pedro@codesourcery.com> (Pedro Alves's message of "Tue, 12 Apr 2011 12:24:31 +0100") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii 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: 2011-04/txt/msg00174.txt.bz2 >>>>> "Pedro" == Pedro Alves writes: >> This patch modifies the mechanism of internalvar. It basically adds >> more manipulation functions to them (`compile_to_ax' and `destroy'), and >> updates the definitions and pointers of existing internalvars. Pedro> Can you explain this? Why would you want to compile an internal Pedro> var to AX, for example? A programmer can pass arguments to a SystemTap probe. In GDB these are represented as convenience variables. We also wanted to be able to collect these probe arguments from tracepoints set at probe points. Rather than write custom code to recognize the variables by name, I thought it would be better to provide a general way to define variables which can be compiled to AX. Pedro> It would be imensely helpful if patches came with a high Pedro> level explanation of why they are necessary in the first Pedro> place. :-/ Sorry about that. Tom