From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Lepiller Subject: Re: Why reproducibility is breaking by metadata? Date: Wed, 03 Jul 2019 08:13:56 +0200 Message-ID: References: <71aab7b233f9f6df36e0248c86b5e020@disroot.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Return-path: Received: from eggs.gnu.org ([2001:470:142:3::10]:46750) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hiYWy-0004bK-RJ for help-guix@gnu.org; Wed, 03 Jul 2019 02:14:13 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hiYWx-00070L-HZ for help-guix@gnu.org; Wed, 03 Jul 2019 02:14:12 -0400 Received: from lepiller.eu ([2a00:5884:8208::1]:52774) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hiYWw-0006wF-4c for help-guix@gnu.org; Wed, 03 Jul 2019 02:14:11 -0400 In-Reply-To: <71aab7b233f9f6df36e0248c86b5e020@disroot.org> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-guix-bounces+gcggh-help-guix=m.gmane.org@gnu.org Sender: "Help-Guix" To: help-guix@gnu.org, znavko@disroot.org Le 3 juillet 2019 06:05:02 GMT+02:00, znavko@disroot=2Eorg a =C3=A9crit : >Hello, Guix Help! I am translating Guix manual and found that the >author is entirely given to reproducibility=2E It leads to such phrases >that metadata breaks reproducibility when he describes >'--save-provenance' flag of 'guix pack' command here: > >'This option is not enabled by default because, like timestamps, >provenance information contributes nothing to the build process=2E In >other words, there is an infinity of channel URLs and commit IDs that >can lead to the same pack=2E Recording such =E2=80=9Csilent=E2=80=9D meta= data in the >output thus potentially breaks the source-to-binary bitwise >reproducibility property=2E ' > >I did not expected such a categorical statement=2E I think, it does not >actually break reproducibility but only complicates checks=2E If we have >to talk about reproducibility to ignoramus, saying 'this option breaks >reproducibility option' have to have remark 'simply put' or 'plainly'=2E I think the key here is "bitwise": it breaks reproducibility in terms of t= he build results not having the same hash=2E Does it make sense?