From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 22635 invoked by alias); 2 Dec 2007 10:50:48 -0000 Received: (qmail 22624 invoked by uid 22791); 2 Dec 2007 10:50:48 -0000 X-Spam-Check-By: sourceware.org Received: from mx-out.libertysurf.net (HELO mail.libertysurf.net) (213.36.80.91) by sourceware.org (qpsmtpd/0.31) with ESMTP; Sun, 02 Dec 2007 10:50:40 +0000 Received: from [192.168.1.3] (83.156.55.88) by mail.libertysurf.net (7.3.118.8) id 470CEC8700859C88; Sun, 2 Dec 2007 12:51:23 +0100 From: Eric Botcazou To: Samuel Tardieu Subject: Re: Rant about ChangeLog entries and commit messages Date: Sun, 02 Dec 2007 10:50:00 -0000 User-Agent: KMail/1.7.1 Cc: gcc@gcc.gnu.org References: <2007-12-02-11-05-39+trackit+sam@rfc1149.net> <200712021127.46198.ebotcazou@libertysurf.fr> <2007-12-02-11-43-44+trackit+sam@rfc1149.net> In-Reply-To: <2007-12-02-11-43-44+trackit+sam@rfc1149.net> MIME-Version: 1.0 Content-Disposition: inline Message-Id: <200712021151.08971.ebotcazou@libertysurf.fr> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org X-SW-Source: 2007-12/txt/msg00020.txt.bz2 > I know this document and I think the part on ChangeLog doesn't achieve > its purpose: > > http://www.gnu.org/prep/standards/standards.html#Change-Logs > > Keep a change log to describe all the changes made to program source > files. The purpose of this is so that people investigating bugs in the > future will know about the changes that might have introduced the bug. > Often a new bug can be found by looking at what was recently changed. > More importantly, change logs can help you eliminate conceptual > inconsistencies between different parts of a program, by giving you a > history of how the conflicting concepts arose and who they came from. Could you elaborate? > When you fix a bug by changing a constant (for example if there has been > an offset by one error or, as I did a few minutes ago in > config/sh/sh.md, there was an error in the argument to consider), this > doesn't always mandate a comment in the code. For example, I think a > description such as the one I wrote when describing the problem > > cmpgeusi_t splitting code compares operand 0 to 0, while this constant > value can only be in operand 1. When compiling the Ada runtime, this > leads to a "cmp/hs #0,r7" instruction which is not valid as "cmp/hs" > operands must be two registers. > > along with the above change would have been a better commit message than > just > > gcc/ > * config/sh/sh.md (cmpgeusi_t): Fix condition. > > which I used as suggested. Not really in my opinion, it's a trivial fix and totally unrelated to Ada in itself, "Fix typo" or "Fix obvious mistake" would have been just fine too. -- Eric Botcazou