From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark H Weaver Subject: bug#40612: guix build system --dry-run is broken Date: Fri, 17 Apr 2020 15:50:23 -0400 Message-ID: <87ftd1uc11.fsf@netris.org> References: <87wo6jax7c.fsf@netris.org> <20200414171632.41dae6fd@alma-ubu> <87d088sn6j.fsf@gnu.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]:48696) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jPX2t-0002hn-Gs for bug-guix@gnu.org; Fri, 17 Apr 2020 15:53:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1jPX2s-0000qP-E0 for bug-guix@gnu.org; Fri, 17 Apr 2020 15:53:03 -0400 Received: from debbugs.gnu.org ([209.51.188.43]:58411) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1jPX2s-0000q6-Ac for bug-guix@gnu.org; Fri, 17 Apr 2020 15:53:02 -0400 Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1jPX2s-0002vh-8C for bug-guix@gnu.org; Fri, 17 Apr 2020 15:53:02 -0400 Sender: "Debbugs-submit" Resent-Message-ID: In-Reply-To: <87d088sn6j.fsf@gnu.org> List-Id: Bug reports for GNU Guix List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-guix-bounces+gcggb-bug-guix=m.gmane-mx.org@gnu.org Sender: "bug-Guix" To: Ludovic =?UTF-8?Q?Court=C3=A8s?= Cc: 40612@debbugs.gnu.org Hi Ludovic, > Bj=C3=B6rn H=C3=B6fling skribis: > >> On Mon, 13 Apr 2020 17:31:56 -0400 >> Mark H Weaver wrote: >> >>> I guess this is related to the recent changes in graft handling, where >>> --dry-run (a.k.a. -n) no longer implies --no-grafts. It's not working >>> well for me. I hadn't updated my system since before those grafting >>> changes were made, and there's a lot for me to rebuild (I don't use >>> substitutes). I was very surprised to see this small output: >> >> Hi Mark, >> >> I can confirm this behavior for "guix system". I'm on > > Yeah, it has to do with the new build handler and the lack of > =E2=80=9Cparallelism=E2=80=9D when building the system derivation: > > https://lists.gnu.org/archive/html/guix-devel/2020-03/msg00337.html > > I think we=E2=80=99ll improve it over time by introducing more parallelism > there. > > Fundamentally though, we have to understand that =E2=80=98--dry-run=E2=80= =99 can only > print the first derivation plans, not those that are dynamically built > as a function of build results. Yes, of course, I agree that it's not possible to present a build plan ahead of time when grafts are enabled. That was the case before these changes, and it's the case today. The only part I don't understand is why you decided that "--dry-run" should no longer imply "--no-grafts". Does it work better for other people? For me, the "--dry-run" output has become utterly useless unless "--no-grafts" is included. Anyway, it's not that important to me. I can just fix it in my own private branch. I filed this report because I thought it might benefit other users to have this fixed upstream. Regards, Mark