From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: Don't complain about changed file when it hasn't changed Date: Tue, 30 Aug 2016 19:14:27 +0300 Message-ID: <83wpiymdy4.fsf@gnu.org> References: <83oa4bbq5b.fsf@gnu.org> <87zinvyrrd.fsf@linux-qg7d.fritz.box> <83eg56nve9.fsf@gnu.org> <9ddf1698-b3e4-b281-69ae-919cff14b408@gmail.com> Reply-To: Eli Zaretskii NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit X-Trace: blaine.gmane.org 1472573850 2732 195.159.176.226 (30 Aug 2016 16:17:30 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Tue, 30 Aug 2016 16:17:30 +0000 (UTC) Cc: emacs-devel@gnu.org To: =?windows-1252?Q?Cl=E9ment?= Pit--Claudel Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Tue Aug 30 18:17:24 2016 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1beliy-000879-7K for ged-emacs-devel@m.gmane.org; Tue, 30 Aug 2016 18:17:20 +0200 Original-Received: from localhost ([::1]:50063 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1beliv-000178-QZ for ged-emacs-devel@m.gmane.org; Tue, 30 Aug 2016 12:17:17 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:49754) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1belgI-0008CV-IH for emacs-devel@gnu.org; Tue, 30 Aug 2016 12:14:35 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1belgF-0000Kr-AJ for emacs-devel@gnu.org; Tue, 30 Aug 2016 12:14:34 -0400 Original-Received: from fencepost.gnu.org ([2001:4830:134:3::e]:56467) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1belgF-0000KL-7U; Tue, 30 Aug 2016 12:14:31 -0400 Original-Received: from 84.94.185.246.cable.012.net.il ([84.94.185.246]:1750 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_128_CBC_SHA1:128) (Exim 4.82) (envelope-from ) id 1belgD-0005Xr-Ao; Tue, 30 Aug 2016 12:14:29 -0400 In-reply-to: <9ddf1698-b3e4-b281-69ae-919cff14b408@gmail.com> (message from =?windows-1252?Q?Cl=E9ment?= Pit--Claudel on Tue, 30 Aug 2016 11:34:13 -0400) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2001:4830:134:3::e X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:206956 Archived-At: > From: Clément Pit--Claudel > Date: Tue, 30 Aug 2016 11:34:13 -0400 > > Another case: a Makefile may generate a.x automatically from b.x. If b.x is updated, a.x will be regenerated on the next run. If a.x was already open in Emacs, Emacs will prompts if the user tries to change it, even if a.x didn't actually change as a result of the re-generation. a.x is not likely to be version-controlled, since it's auto-generated. This will cause much more trouble to the project that uses this Makefile, because Make does only consider the time stamp. The usual solution for this (and we have it in the Emacs build procedure as well) is to use the move-if-change script, or something similar. That script makes sure that the file doesn't get updated unless its contents really changed.