From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pigeon.gentoo.org ([208.92.234.80] helo=lists.gentoo.org) by finch.gentoo.org with esmtp (Exim 4.60) (envelope-from ) id 1NDS2I-0006pp-2A for garchives@archives.gentoo.org; Thu, 26 Nov 2009 00:16:39 +0000 Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id C2AC2E0ABA; Thu, 26 Nov 2009 00:16:04 +0000 (UTC) Received: from mail-ew0-f224.google.com (mail-ew0-f224.google.com [209.85.219.224]) by pigeon.gentoo.org (Postfix) with ESMTP id 605DCE0ABA for ; Thu, 26 Nov 2009 00:16:04 +0000 (UTC) Received: by ewy24 with SMTP id 24so294615ewy.26 for ; Wed, 25 Nov 2009 16:16:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=gamma; h=domainkey-signature:received:received:date:from:to:subject :message-id:in-reply-to:references:x-mailer:mime-version :content-type; bh=c4iHSkhKfdp27BuZWdBctxo/Q1cbBMcf1COFgF18C7E=; b=Z+3pkPsbsUoO6qKyiOl6G520T6tJNqeImZ0HAQ9i1WjRidnn64zu6e9jcS4Calzdr3 rh2A8OZ7x87mmzTapC27ymQ9Uz456XEonoPmPdntxz0WtHOoQJevpGdd4N8PD4TMcT0h T4XgoK0tpfUy1nQXbgVkspxVsckA8NzQtXkYk= DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=date:from:to:subject:message-id:in-reply-to:references:x-mailer :mime-version:content-type; b=toLaxe6REmWCvZtumIos2+qGqTvoZ800ZGn7/LTaMjnTERE+8qSLqf0UmV38jRVe8K dKlz6ZBUHTJHs1OErFq1ofUafVTC9e6Yw3Kbi2XcU6B5JwsFRcQFnA0u+dNBuDFOOr2n sPMyJjdyqujt2B2cOEFXxMwIm841OICObYjD0= Received: by 10.216.89.135 with SMTP id c7mr551775wef.62.1259194563676; Wed, 25 Nov 2009 16:16:03 -0800 (PST) Received: from snowmobile (92-235-187-79.cable.ubr18.sgyl.blueyonder.co.uk [92.235.187.79]) by mx.google.com with ESMTPS id p10sm515285gvf.28.2009.11.25.16.16.02 (version=TLSv1/SSLv3 cipher=RC4-MD5); Wed, 25 Nov 2009 16:16:03 -0800 (PST) Date: Thu, 26 Nov 2009 00:15:40 +0000 From: Ciaran McCreesh To: gentoo-dev@lists.gentoo.org Subject: Re: [gentoo-dev] mtime preservation Message-ID: <20091126001540.08a6e193@snowmobile> In-Reply-To: <19213.46817.620937.656202@a1i15.kph.uni-mainz.de> References: <19184.25176.380022.392451@a1i15.kph.uni-mainz.de> <20091108191439.3fcee79d@snowcone> <7c612fc60911090718y144319f5lc9827a5e2e153c2@mail.gmail.com> <20091109153429.502e272f@snowcone> <19193.4389.637969.727075@a1i15.kph.uni-mainz.de> <20091119221248.539eedd9@snowmobile> <7c612fc60911191614h5e37c849y50ad217a828fa744@mail.gmail.com> <20091120001820.7274bdf7@snowmobile> <4B07362D.2010108@gentoo.org> <7c612fc60911231049n4a51ddb0u30ae72d8ed93cdec@mail.gmail.com> <7c612fc60911251313i705a182as6cf50402c7829beb@mail.gmail.com> <20091125212718.5deb42f8@snowcone> <20091125221327.324e11fb@snowcone> <19213.46817.620937.656202@a1i15.kph.uni-mainz.de> X-Mailer: Claws Mail 3.7.3 (GTK+ 2.16.5; i686-pc-linux-gnu) Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-dev@lists.gentoo.org Reply-to: gentoo-dev@lists.gentoo.org Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; boundary="Sig_/Yt.LFFo.7/i=IxXLXA.d6J4"; protocol="application/pgp-signature" X-Archives-Salt: 3ec753ce-e39d-4f27-8204-86a825bc0beb X-Archives-Hash: bdecb081650697fc14a4e3044956db76 --Sig_/Yt.LFFo.7/i=IxXLXA.d6J4 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Wed, 25 Nov 2009 23:59:45 +0100 Ulrich Mueller wrote: > Real examples would be issues like bugs 83877 [1] or 263387 [2]. > Nothing that could be easily dismissed or worked around. Both issues > are fixed with Portage since a long time. Yes, those are examples of packages relying upon something that is undefined behaviour, and that behaves differently depending upon the Portage version you use. > I don't know of any example where non-preservation of nanosecond > timestamps would cause problems. Not non-preservation. Partial and inconsistent corruption. srcfile gets installed with its mtime preserved, because it is installed using rename. objfile, whose mtime should be a bit later than srctime's, gets installed with its mtime corrupted to be slightly less than it should be, and less than srctime's, because it is installed the slow way. A program checks that objfile's mtime is greater than or equal to srcfile's mtime. That check will fail, and reinstalls will randomly fix and break it depending upon which way the corruption goes. --=20 Ciaran McCreesh --Sig_/Yt.LFFo.7/i=IxXLXA.d6J4 Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.12 (GNU/Linux) iEYEARECAAYFAksNyK4ACgkQ96zL6DUtXhFx0QCgm0NgHefKOSWAxsRKIyKcUzPd nEoAn0S5rdjCaS2XBZAqXGsKPSw/KQHa =GQvB -----END PGP SIGNATURE----- --Sig_/Yt.LFFo.7/i=IxXLXA.d6J4--