Subject: bug#43890: closed (Re: bug#43890: ‘package-input-rewriting/spec’can introduce unnecessary variants)

From: [email-masked] (GNU bug Tracking System)
Date: Tue, 20 Oct 2020 14:36:02 +0000

Your bug report

#43890: ‘package-input-rewriting/spec’ can introduce unnecessary variants

which was filed against the guix package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to [email-masked].

-- 
43890: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=43890
GNU Bug Tracking System
Contact [email-masked] with problems

Subject: Re: bug#43890: ‘package-input-rewriting/spec’ can introduce unnecessary variants
From: Ludovic Courtès <[email-masked]>
To: [email-masked]
Date: Tue, 20 Oct 2020 16:35:33 +0200
List-Id: <debbugs-submit.debbugs.gnu.org>

Ludovic Courtès <[email-masked]> skribis:

> Consider this example:
>
> $ guix describe
> Generacio 162	Oct 01 2020 00:23:38	(nuna)
>   guix 7607ace
>     repository URL: https://git.savannah.gnu.org/git/guix.git
>     branch: master
>     commit: 7607ace5091aea0157ba5c8a508129cc5fc4f931
> $ guix build inkscape --no-grafts -d
> /gnu/store/arjs5hb4wmy6dh5d3y8bbs808ki9abf8-inkscape-1.0.1.drv
> $ guix build inkscape --no-grafts -d --with-graft=glib=glib-networking
> /gnu/store/zd8mm3w6x9c97anfaly77fz28s5y3i5h-inkscape-1.0.1.drv
> $ guix build inkscape --no-grafts -d --with-graft=libreoffice=abiword
> /gnu/store/arjs5hb4wmy6dh5d3y8bbs808ki9abf8-inkscape-1.0.1.drv
>
> The last one is fine: it has no effect.
>
> The second one is problematic: since we’re using ‘--no-grafts’, the
> ‘--with-graft’ option should have absolutely no effect; yet, it yields a
> different derivation.

Fixed in 8db4ebb0cd9bfdcf1aea63eb8d20eb6af0c87c93.  \o/

It makes ‘--with-debug-info’ more practical.

The difficulty is to find out where the difference is and what piece of
code introduced a non-eq?-but-equal package.  Likewise, the test suite
catches corner cases that can take a while to address.

Related to that, commit 6b4663363c061071c10209f71aed1017a241af6c deletes
duplicates in ‘bag->derivation’, which should make the whole thing less
sensitive to the introduction of non-eq?-but-equal packages in the
graph.

Ludo’.

Subject: ‘package-input-rewriting/spec’ can introduce unnecessary variants
From: Ludovic Courtès <[email-masked]>
To: [email-masked]
Date: Fri, 09 Oct 2020 22:14:08 +0200
List-Id: <debbugs-submit.debbugs.gnu.org>

Consider this example:

--8<---------------cut here---------------start------------->8---
$ guix describe
Generacio 162	Oct 01 2020 00:23:38	(nuna)
  guix 7607ace
    repository URL: https://git.savannah.gnu.org/git/guix.git
    branch: master
    commit: 7607ace5091aea0157ba5c8a508129cc5fc4f931
$ guix build inkscape --no-grafts -d
/gnu/store/arjs5hb4wmy6dh5d3y8bbs808ki9abf8-inkscape-1.0.1.drv
$ guix build inkscape --no-grafts -d --with-graft=glib=glib-networking
/gnu/store/zd8mm3w6x9c97anfaly77fz28s5y3i5h-inkscape-1.0.1.drv
$ guix build inkscape --no-grafts -d --with-graft=libreoffice=abiword
/gnu/store/arjs5hb4wmy6dh5d3y8bbs808ki9abf8-inkscape-1.0.1.drv
--8<---------------cut here---------------end--------------->8---

The last one is fine: it has no effect.

The second one is problematic: since we’re using ‘--no-grafts’, the
‘--with-graft’ option should have absolutely no effect; yet, it yields a
different derivation.

On closer inspection, we see that the core issue is that
‘gobject-introspection’ in the second case ends up with ‘libffi’ twice
in its ‘*-guile-builder’ script, a problem similar to
<https://issues.guix.gnu.org/38100>.  (‘libffi’ is propagated by both
‘glib’ and ‘gobject-introspection’.)

Ludo’.