From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 29689 invoked by alias); 9 Apr 2008 17:06:17 -0000 Received: (qmail 29675 invoked by uid 22791); 9 Apr 2008 17:06:15 -0000 X-Spam-Check-By: sourceware.org Received: from mtaout1.012.net.il (HELO mtaout1.012.net.il) (84.95.2.1) by sourceware.org (qpsmtpd/0.31) with ESMTP; Wed, 09 Apr 2008 17:05:50 +0000 Received: from HOME-C4E4A596F7 ([80.230.253.114]) by i-mtaout1.012.net.il (HyperSendmail v2007.08) with ESMTPA id <0JZ200I74ISKNR40@i-mtaout1.012.net.il> for gdb-patches@sources.redhat.com; Wed, 09 Apr 2008 20:19:33 +0300 (IDT) Date: Wed, 09 Apr 2008 18:04:00 -0000 From: Eli Zaretskii Subject: Re: [RFA] Document fixed/floating variable objects and thread-id. In-reply-to: <200804091910.56855.ghost@cs.msu.su> X-012-Sender: halo1@inter.net.il To: Vladimir Prus Cc: gdb-patches@sources.redhat.com Reply-to: Eli Zaretskii Message-id: Content-transfer-encoding: 7BIT References: <200804041320.00361.vladimir@codesourcery.com> <200804091910.56855.ghost@cs.msu.su> 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: 2008-04/txt/msg00172.txt.bz2 > From: Vladimir Prus > Date: Wed, 9 Apr 2008 19:10:56 +0400 > Cc: gdb-patches@sources.redhat.com > > On Wednesday 09 April 2008 19:00:28 Eli Zaretskii wrote: > > > From: Vladimir Prus > > > Date: Wed, 09 Apr 2008 15:59:14 +0400 > > > > > > >> +fixed variable object, the expression is parsed when the variable > > > >> +object is created, including associating indentifiers to specific > > > >> +variables. The meaning of expression never changes. A floating > > > >> +variable object has its expression reparsed each time the variable > > > >> +object is updated. In particular, the meaning of identifiers can > > > >> +change every time. > > > > > > > > Instead of ``meaning'' here, isn't it better to say ``value''? > > > > > > Identifier does not have a value. Think of 'i' -- it's just a name. > > > It is then associated to a specific variable, which variable has value. > > > What I mean is that association between identifiers to variables can > > > change for floating variable objects. Of course, the values can also > > > change, but values can change even for fixed variable objects. > > > > > > What's the best way to express this? > > > > I don't know yet: what is an ``identifier'' in this context? You > > don't mean symbols in the source language of the program being > > debugged, as in your example with `i', do you? > > I mean exactly that. variable object is created for an expression. > That expression, among other things, has identifiers that are resolved > to refer to variables in the program. Then how about ``the values of variables whose names appear in the expressions are re-evaluated every time''?