From mboxrd@z Thu Jan 1 00:00:00 1970 From: ludo@gnu.org (Ludovic =?utf-8?Q?Court=C3=A8s?=) Subject: Re: Determinism issue Date: Sat, 19 Jul 2014 15:52:57 +0200 Message-ID: <8761itfoau.fsf@gnu.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Return-path: Received: from eggs.gnu.org ([2001:4830:134:3::10]:43465) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X8V4X-0006oc-6l for guix-devel@gnu.org; Sat, 19 Jul 2014 09:53:14 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1X8V4R-0002jC-PK for guix-devel@gnu.org; Sat, 19 Jul 2014 09:53:09 -0400 Received: from hera.aquilenet.fr ([2a01:474::1]:34446) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X8V4R-0002iz-I5 for guix-devel@gnu.org; Sat, 19 Jul 2014 09:53:03 -0400 In-Reply-To: (Ondra Pelech's message of "Fri, 18 Jul 2014 04:23:59 +0200") List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org Sender: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org To: Ondra Pelech Cc: guix-devel@gnu.org Hello, Roughly, there=E2=80=99s not much difference between what Guix and Nixpkgs provide in terms of build determinism, but this is clearly something we=E2=80=99re interested in. Guix may be slightly stricter in that chroot builds are the default, and it doesn=E2=80=99t rely on /bin/sh being in the chroot (unlike Nixpkgs.) You mention profile-guided optimizations. This is *disabled* by default in GCC, AFAIK, so GCC is definitely deterministic. Another thing we do is build Binutils with --enable-deterministic-archives, which makes =E2=80=98ar=E2=80=99 archives = with zeroed timestamps by default. For other examples of non-determinism issues, the Debian project has a nice summary: . Similarly, some time ago, I started looking a fixed-point builds, though I didn=E2=80=99t complete that: https://lists.gnu.org/archive/html/guix-devel/2013-09/msg00159.html Thanks, Ludo=E2=80=99.