From mboxrd@z Thu Jan  1 00:00:00 1970
From: ludo@gnu.org (Ludovic =?utf-8?Q?Court=C3=A8s?=)
Subject: Re: reproducibility
Date: Tue, 12 Jan 2016 22:37:46 +0100
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	(Federico Beffa's message of "Tue, 12 Jan 2016 21:11:47 +0100")
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To: Federico Beffa <beffa@ieee.org>
Cc: Guix-devel <guix-devel@gnu.org>

Federico Beffa <beffa@ieee.org> skribis:

> On Sun, Jan 10, 2016 at 9:49 PM, Ludovic Court=C3=A8s <ludo@gnu.org> wrot=
e:
>> Federico Beffa <beffa@ieee.org> skribis:
>>
>>> I've noticed that a derivation is a function of the order of the
>>> inputs. As an example, the following two input orders give rise to two
>>> distinct derivations:
>>>
>>> A)
>>>
>>>     (inputs
>>>      `(("texlive" ,texlive)
>>>        ("texinfo" ,texinfo)
>>>        ("m4" ,m4)
>>>        ("libx11" ,libx11))
>>>
>>> B)
>>>     (inputs
>>>      `(("texinfo" ,texinfo)
>>>        ("texlive" ,texlive)
>>>        ("m4" ,m4)
>>>        ("libx11" ,libx11))
>>>
>>> Is this intentional?
>>
>> Yes.  There are several places where order matters, most importantly
>> search paths, and these are computed from the input lists.
>
> If order matters, it would probably be more robust to force internally
> a specific order rather than relying on the (often random) order
> defined in a package recipe (possibly created by an importer, ...).

Most of the time any order would work, but I can imagine situations
where the packager could purposefully choose a specific order.  So I=E2=80=
=99d
rather not do any automatic sorting, if that=E2=80=99s what you have in min=
d.

Thanks,
Ludo=E2=80=99.