From mboxrd@z Thu Jan  1 00:00:00 1970
From: ludo@gnu.org (Ludovic =?utf-8?Q?Court=C3=A8s?=)
Subject: Re: dry-run defunct
Date: Sun, 17 Jul 2016 15:40:56 +0200
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References: <20160717103218.GA25877@thebird.nl> <20160717110535.GA9940@solar>
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In-Reply-To: <20160717110535.GA9940@solar> (Andreas Enge's message of "Sun, 17
	Jul 2016 13:05:35 +0200")
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To: Andreas Enge <andreas@enge.fr>
Cc: guix-devel <guix-devel@gnu.org>

Andreas Enge <andreas@enge.fr> skribis:

> On Sun, Jul 17, 2016 at 12:32:18PM +0200, Pjotr Prins wrote:
>> Did --dry-run stop working, or is it me? Basically the flag is ignored
>> on the latest checkout.
>
> It does not quite work in the presence of grafts. As far as I understand
> from testing, the ungrafted packages are still built, and then it stops
> only before grafting.

Specifically, to determine whether a binary needs to be grafted, Guix
must check whether that binary depends on one of the things that we
would graft.

To do that, it must either have access to substitute information, or
have a local build of the thing at hand.

Thus, when substitutes are lacking, it will tend to build things right
away so that it can answer that question.

I agree this isn=E2=80=99t great, but I=E2=80=99m not sure how to improve o=
n that.
(Nevertheless, it is better than answering the question based on
compile-time dependencies as was done before.)

Ludo=E2=80=99.