X-Recipient:	archive-cygwin AT delorie DOT com
X-SWARE-Spam-Status:	No, hits=-2.2 required=5.0 tests=AWL,BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,T_TO_NO_BRKTS_FREEMAIL
X-Spam-Check-By:	sourceware.org
Message-ID:	<4BE11A07.1040308@gmail.com>
Date:	Wed, 05 May 2010 08:11:03 +0100
From:	Dave Korn <dave DOT korn DOT cygwin AT googlemail DOT com>
User-Agent:	Thunderbird 2.0.0.17 (Windows/20080914)
MIME-Version:	1.0
To:	cygwin AT cygwin DOT com
Subject:	Re: Cygwin make target is never determined up to date
References:	<28454344 DOT post AT talk DOT nabble DOT com> <4BE0F722 DOT 1040009 AT bopp DOT net> <28456659 DOT post AT talk DOT nabble DOT com> <4BE0FC52 DOT 80708 AT bopp DOT net>
In-Reply-To:	<4BE0FC52.80708@bopp.net>
Mailing-List:	contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Id:	<cygwin.cygwin.com>
List-Subscribe:	<mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive:	<http://sourceware.org/ml/cygwin/>
List-Post:	<mailto:cygwin AT cygwin DOT com>
List-Help:	<mailto:cygwin-help AT cygwin DOT com>, <http://sourceware.org/ml/#faqs>
Sender:	cygwin-owner AT cygwin DOT com
Mail-Followup-To:	cygwin AT cygwin DOT com
Delivered-To:	mailing list cygwin AT cygwin DOT com

On 05/05/2010 06:04, Jeremy Bopp wrote:
> MichaelKim wrote:

>>          Prerequisite `../bin/build/chrome' is newer than
>>                  target `../bin/build/chrome/alt.jar'.
>>         Must remake target `../bin/build/chrome/alt.jar'.

> So let me get this straight.  The JAR file you're trying to build is
> within a directory which is listed as a prerequisite of that JAR file?
> Unless I'm completely off base, it would seem to be that this is
> expected behavior then.  If you mess with the contents of a directory,
> such as by adding a file to it, the last modified timestamp of the
> directory is going to be updated.  I would expect that to happen after
> the file is added to the directory which could very well be *after* the
> last modified timestamp of the file is set.  Thus the directory will
> appear newer than the file.

  Yep:

>     $(chrome_jar_file): $(jar_sources) $(jar_target_dir)

  The idea is supposed to be to make the jar file depend on the output dir, so
that if the output dir doesn't exist, the $(jar_target_dir) rule will get
invoked to mkdir it; but it doesn't anticipate that the timestamp of an
existing dir changes everytime you touch the files within it.

  For a discussion of better ways to create an output dir in make, see:

http://www.cmcrossroads.com/cm-articles/columns/ask-mr-make

The particular article you're looking for is #26, "Making directories in GNU
Make":

http://www.cmcrossroads.com/ask-mr-make/6936-making-directories-in-gnu-make

  I don't know why this would be working on the old XP machine, unless it's
running an older version of cygwin that had a bug or didn't implement updating
directory timestamps.

    cheers,
      DaveK


--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple

- Raw text -