--- /dev/null
+Return-Path: <amdragon@mit.edu>\r
+X-Original-To: notmuch@notmuchmail.org\r
+Delivered-To: notmuch@notmuchmail.org\r
+Received: from localhost (localhost [127.0.0.1])\r
+ by olra.theworths.org (Postfix) with ESMTP id 2BFCC431FBD\r
+ for <notmuch@notmuchmail.org>; Wed, 19 Feb 2014 11:55:12 -0800 (PST)\r
+X-Virus-Scanned: Debian amavisd-new at olra.theworths.org\r
+X-Spam-Flag: NO\r
+X-Spam-Score: -0.7\r
+X-Spam-Level: \r
+X-Spam-Status: No, score=-0.7 tagged_above=-999 required=5\r
+ tests=[RCVD_IN_DNSWL_LOW=-0.7] autolearn=disabled\r
+Received: from olra.theworths.org ([127.0.0.1])\r
+ by localhost (olra.theworths.org [127.0.0.1]) (amavisd-new, port 10024)\r
+ with ESMTP id xEYHbvnwpr6n for <notmuch@notmuchmail.org>;\r
+ Wed, 19 Feb 2014 11:55:06 -0800 (PST)\r
+Received: from dmz-mailsec-scanner-4.mit.edu (dmz-mailsec-scanner-4.mit.edu\r
+ [18.9.25.15])\r
+ (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits))\r
+ (No client certificate requested)\r
+ by olra.theworths.org (Postfix) with ESMTPS id AD654431FAE\r
+ for <notmuch@notmuchmail.org>; Wed, 19 Feb 2014 11:55:05 -0800 (PST)\r
+X-AuditID: 1209190f-f790b6d000000c3a-e4-53050c1672c9\r
+Received: from mailhub-auth-1.mit.edu ( [18.9.21.35])\r
+ (using TLS with cipher AES256-SHA (256/256 bits))\r
+ (Client did not present a certificate)\r
+ by dmz-mailsec-scanner-4.mit.edu (Symantec Messaging Gateway) with SMTP\r
+ id B7.CC.03130.61C05035; Wed, 19 Feb 2014 14:55:02 -0500 (EST)\r
+Received: from outgoing.mit.edu (outgoing-auth-1.mit.edu [18.9.28.11])\r
+ by mailhub-auth-1.mit.edu (8.13.8/8.9.2) with ESMTP id s1JJt11U001804; \r
+ Wed, 19 Feb 2014 14:55:02 -0500\r
+Received: from awakening.csail.mit.edu (awakening.csail.mit.edu [18.26.4.91])\r
+ (authenticated bits=0)\r
+ (User authenticated as amdragon@ATHENA.MIT.EDU)\r
+ by outgoing.mit.edu (8.13.8/8.12.4) with ESMTP id s1JJswCu026247\r
+ (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NOT);\r
+ Wed, 19 Feb 2014 14:55:00 -0500\r
+Received: from amthrax by awakening.csail.mit.edu with local (Exim 4.80)\r
+ (envelope-from <amdragon@MIT.EDU>)\r
+ id 1WGDEQ-0001A9-44; Wed, 19 Feb 2014 14:54:58 -0500\r
+Date: Wed, 19 Feb 2014 14:54:57 -0500\r
+From: Austin Clements <amdragon@MIT.EDU>\r
+To: Tomi Ollila <tomi.ollila@iki.fi>\r
+Subject: Re: [PATCH 1/1] emacs: always write emacs/.eldeps when the target is\r
+ remade\r
+Message-ID: <20140219195457.GD13537@mit.edu>\r
+References: <1390645309-2326-1-git-send-email-tomi.ollila@iki.fi>\r
+ <20140213071026.GX4375@mit.edu> <m2sirn1nik.fsf@guru.guru-group.fi>\r
+ <20140213074944.GY4375@mit.edu> <m2bny9ebvk.fsf@guru.guru-group.fi>\r
+ <20140214215736.GD4375@mit.edu>\r
+MIME-Version: 1.0\r
+Content-Type: text/plain; charset=us-ascii\r
+Content-Disposition: inline\r
+In-Reply-To: <20140214215736.GD4375@mit.edu>\r
+User-Agent: Mutt/1.5.21 (2010-09-15)\r
+X-Brightmail-Tracker:\r
+ H4sIAAAAAAAAA+NgFmpmleLIzCtJLcpLzFFi42IR4hRV1hXjYQ02+L/OwuL6zZnMFm9WzmN1\r
+ YPI4/HUhi8ezVbeYA5iiuGxSUnMyy1KL9O0SuDKm7NjBWLDarOJ243bGBsYjWl2MnBwSAiYS\r
+ X//NYYawxSQu3FvPBmILCcxmkvhzXKeLkQvI3sgoMe/GFhaIxGkmiaaWQIjEEkaJ2+f+gnWz\r
+ CKhKXHj1hh3EZhPQkNi2fzkjiC0ioCLxoG09K4jNLCAt8e13MxOILSwQJjFz0WmwXl4BHYlD\r
+ 9x6yQQz9zChxfNs8RoiEoMTJmU9YIJq1JG78ewnUzAE2aPk/DpAwJ1BvZ18b2HxRoF1TTm5j\r
+ m8AoNAtJ9ywk3bMQuhcwMq9ilE3JrdLNTczMKU5N1i1OTszLSy3SNdHLzSzRS00p3cQIDmtJ\r
+ /h2M3w4qHWIU4GBU4uFluMoSLMSaWFZcmXuIUZKDSUmUdx0Ta7AQX1J+SmVGYnFGfFFpTmrx\r
+ IUYJDmYlEd5oNqAcb0piZVVqUT5MSpqDRUmct9biV5CQQHpiSWp2ampBahFMVoaDQ0mCt5Qb\r
+ qFGwKDU9tSItM6cEIc3EwQkynAdo+CSQGt7igsTc4sx0iPwpRkUpcd7XHEAJAZBERmkeXC8s\r
+ 7bxiFAd6RZh3Okg7DzBlwXW/AhrMBDTYay8jyOCSRISUVAOj3bfr6rtiiqcmcz2aNc3HQ9N6\r
+ XXfUKXbJp0mPGEJ3Pf95WEvm6bzAf4/iLy+dbf3V6qX6BTth85rsN6tLoueeniUaWNhzLYtF\r
+ bYHcJkttsXR/De0n8y1P5k9ZfXaWZJvPaWPVA9rKB3zU+xmnCps/yE96d/CHw6zpgReU69t4\r
+ /oWWh5xodVRRYinOSDTUYi4qTgQAM4ZivhYDAAA=\r
+Cc: notmuch@notmuchmail.org\r
+X-BeenThere: notmuch@notmuchmail.org\r
+X-Mailman-Version: 2.1.13\r
+Precedence: list\r
+List-Id: "Use and development of the notmuch mail system."\r
+ <notmuch.notmuchmail.org>\r
+List-Unsubscribe: <http://notmuchmail.org/mailman/options/notmuch>,\r
+ <mailto:notmuch-request@notmuchmail.org?subject=unsubscribe>\r
+List-Archive: <http://notmuchmail.org/pipermail/notmuch>\r
+List-Post: <mailto:notmuch@notmuchmail.org>\r
+List-Help: <mailto:notmuch-request@notmuchmail.org?subject=help>\r
+List-Subscribe: <http://notmuchmail.org/mailman/listinfo/notmuch>,\r
+ <mailto:notmuch-request@notmuchmail.org?subject=subscribe>\r
+X-List-Received-Date: Wed, 19 Feb 2014 19:55:12 -0000\r
+\r
+Quoth myself on Feb 14 at 4:58 pm:\r
+> Quoth Tomi Ollila on Feb 14 at 9:24 pm:\r
+> > On Thu, Feb 13 2014, Austin Clements <amdragon@MIT.EDU> wrote:\r
+> > \r
+> > > Quoth Tomi Ollila on Feb 13 at 9:26 am:\r
+> > >> On Thu, Feb 13 2014, Austin Clements <amdragon@MIT.EDU> wrote:\r
+> > >> \r
+> > >> > Quoth Tomi Ollila on Jan 25 at 12:21 pm:\r
+> > >> >> So that the target is newer than its prerequisites.\r
+> > >> >> ---\r
+> > >> >> emacs/Makefile.local | 3 +--\r
+> > >> >> 1 file changed, 1 insertion(+), 2 deletions(-)\r
+> > >> >> \r
+> > >> >> diff --git a/emacs/Makefile.local b/emacs/Makefile.local\r
+> > >> >> index 42bfbd9..d5d402e 100644\r
+> > >> >> --- a/emacs/Makefile.local\r
+> > >> >> +++ b/emacs/Makefile.local\r
+> > >> >> @@ -32,8 +32,7 @@ emacs_bytecode = $(emacs_sources:.el=.elc)\r
+> > >> >> ifeq ($(HAVE_EMACS),1)\r
+> > >> >> $(dir)/.eldeps: $(dir)/Makefile.local $(dir)/make-deps.el $(emacs_sources)\r
+> > >> >> $(call quiet,EMACS) --directory emacs -batch -l make-deps.el \\r
+> > >> >> - -f batch-make-deps $(emacs_sources) > $@.tmp && \\r
+> > >> >> - (cmp -s $@.tmp $@ || mv $@.tmp $@)\r
+> > >> >> + -f batch-make-deps $(emacs_sources) > $@.tmp && mv $@.tmp $@\r
+> > >> >> -include $(dir)/.eldeps\r
+> > >> >> endif\r
+> > >> >> CLEAN+=$(dir)/.eldeps $(dir)/.eldeps.tmp\r
+> > >> >\r
+> > >> > Is this just so the rule doesn't get run again on the next make\r
+> > >> > invocation (unless, of course, a dependent changed)?\r
+> > >> \r
+> > >> Basically yes. I did multiple builds in rapid succession when developing\r
+> > >> something and this thing confused me quite a lot in the beginning...\r
+> > >> \r
+> > >> > Interestingly, if any of the dependents have changed, but in ways that\r
+> > >> > don't affect .eldeps, this change will make the build more expensive\r
+> > >> > because it will trigger a make restart after .eldeps is updated.\r
+> > >> \r
+> > >> I wondered what was the reason for the recipe you've chosen here, has\r
+> > >> it something to do with inodes or something ;) (and were going to ask\r
+> > >> an alternative to touch (or even : > $@) the target...\r
+> > >> \r
+> > >> ... but now I understand. E.g. change in notmuch-lib.el will cause *all* \r
+> > >> .el files to be re-bytecompiled after this change. \r
+> > >\r
+> > > This is unrelated to the cmp in the recipe. A change in\r
+> > > notmuch-lib.el *must* cause almost all .el files to be recompiled\r
+> > > because they almost all require it and may use macros from it. If you\r
+> > > touch, e.g., notmuch-hello.el, you'll see that very little is rebuilt\r
+> > > (with or without this patch).\r
+> > >\r
+> > >> An alternative to this patch would be adding a message to the rule\r
+> > >> which informs user to touch .eldeps to avoid re-doing .eldeps if\r
+> > >> that irritates one :D\r
+> > >> \r
+> > >> something like:\r
+> > >> \r
+> > >> (cmp -s $@.tmp $@ && \\r
+> > >> echo "touch $@ to avoid redoing this target" || mv $@.tmp $@)\r
+> > >\r
+> > > I think this patch is good as it is; I was just pointing out that the\r
+> > > change also has a performance drawback in some situations. (Knowing\r
+> > > make, there's probably *some* way to get the best of both worlds and\r
+> > > it's probably really ugly.)\r
+> > \r
+> > Ah, now I understand, because emacs/Makefile.local includes emacs/.eldeps\r
+> > when it notices mtime of emacs/.eldeps changes it restarts itself...\r
+> > \r
+> > ... to compare with current behaviour:\r
+> > \r
+> > $ make\r
+> > ...\r
+> > $ touch emacs/notmuch.el\r
+> > $ make\r
+> > ...\r
+> > $ make\r
+> > Use "make V=1" to see the verbose compile lines.\r
+> > EMACS emacs/.eldeps\r
+> > make: Nothing to be done for `all'.\r
+> > $ make\r
+> > Use "make V=1" to see the verbose compile lines.\r
+> > EMACS emacs/.eldeps\r
+> > make: Nothing to be done for `all'.\r
+> > $ make\r
+> > Use "make V=1" to see the verbose compile lines.\r
+> > EMACS emacs/.eldeps\r
+> > make: Nothing to be done for `all'.\r
+> > \r
+> > It will rerun emacs -L emacs -batch -l make-deps.el -f batch-make-deps ...\r
+> > over and over again...\r
+> > \r
+> > I thought I figured out a solution involving .eldeps.stamp file but\r
+> > that turned out to be no-go... (circular dependency netween .eldeps.stamp\r
+> > and Makefile.local).\r
+> > \r
+> > So, with this if one edits emacs/* files and keeps building byte-compiled\r
+> > versions often, make will both run EMACS emacs/.eldeps and restarting\r
+> > -- and when moving to edit other files both of the above stops. Without\r
+> > this change after editing emacs/* files EMACS emacs/.eldeps will be\r
+> > executed until it is touched or make clean executed (I wonder how make\r
+> > handles rebuilding emacs/.eldeps while doing make clean ;)\r
+> > \r
+> > \r
+> > Tomi\r
+> \r
+> Here's a way that works, but it's more complicated than your patch and\r
+> doesn't seem to perform any better:\r
+> \r
+> diff --git a/emacs/Makefile.local b/emacs/Makefile.local\r
+> index 42bfbd9..8a1f1c2 100644\r
+> --- a/emacs/Makefile.local\r
+> +++ b/emacs/Makefile.local\r
+> @@ -29,14 +29,28 @@ emacs_bytecode = $(emacs_sources:.el=.elc)\r
+> # the byte compiler may load an old .elc file when processing a\r
+> # "require" or we may fail to rebuild a .elc that depended on a macro\r
+> # from an updated file.\r
+> +#\r
+> +# We do this in two rules. .eldeps is the "real" dependencies file\r
+> +# and will be rebuilt if and only if a .el source file changes. We\r
+> +# could include this directly, but then whenever a .el file changed\r
+> +# (and .eldeps's mtime changed), make would restart immediately after\r
+> +# the include below. To avoid this, we create a second file,\r
+> +# .eldeps.x, that we only update when its *contents* differ from\r
+> +# .eldeps. .eldeps will often have an mtime older than .eldeps.x (any\r
+> +# .el file change that does not change dependencies will cause this),\r
+> +# so the .eldeps.x rule will often run, but it executes quickly and\r
+> +# quietly and will not trigger a make restart unless the dependencies\r
+> +# actually change.\r
+\r
+Here's a version of this comment that gets to the point directly:\r
+\r
+# We could include .eldeps directly, but that would cause a make\r
+# restart whenever any .el file was modified, even if dependencies\r
+# didn't change, because the mtime of .eldeps will change. Instead,\r
+# we include a second file, .eldeps.x, which we ensure always has the\r
+# same content as .eldeps, but its mtime only changes when dependency\r
+# information changes, in which case a make restart is necessary\r
+# anyway.\r
+\r
+> ifeq ($(HAVE_EMACS),1)\r
+> $(dir)/.eldeps: $(dir)/Makefile.local $(dir)/make-deps.el $(emacs_sources)\r
+> $(call quiet,EMACS) --directory emacs -batch -l make-deps.el \\r
+> -f batch-make-deps $(emacs_sources) > $@.tmp && \\r
+> - (cmp -s $@.tmp $@ || mv $@.tmp $@)\r
+> --include $(dir)/.eldeps\r
+> + mv $@.tmp $@\r
+> +$(dir)/.eldeps.x: $(dir)/.eldeps\r
+> + @cmp -s $^ $@ || cp $^ $@\r
+> +-include $(dir)/.eldeps.x\r
+> endif\r
+> -CLEAN+=$(dir)/.eldeps $(dir)/.eldeps.tmp\r
+> +CLEAN+=$(dir)/.eldeps $(dir)/.eldeps.tmp $(dir)/.eldeps.x\r
+> \r
+> ifeq ($(HAVE_EMACS),1)\r
+> %.elc: %.el $(global_deps)\r
projects / notmuch-archives.git / commitdiff