bug#61841: bug#61255: [PATCH 0/5] Add support for the RPM format to "guix pack"

[Ludovic Courtès]

Hi Maxim,

Ludovic Courtès <ludo@gnu.org> skribis:

> I’m really not sure what the impact of
> 68775338a510f84e63657ab09242d79e726fa457 is, nor whether it was the only
> solution to the problem.
>
> One thing that probably happens is that (default-guile) is now never
> used for <computed-file>, contrary to what was happening before.  The
> spirit is that (default-guile) would be used as the default for all the
> declarative file-like objects; gexp compilers refer to (default-guile),
> not (%guile-for-build).
>
> Importantly, (%guile-for-build) is a derivation, possibly built for
> another system, whereas (default-guile) is a package, which allows
> ‘lower-object’ to return the derivation for the right system type.

Commit 68775338a510f84e63657ab09242d79e726fa457 turned out to have
unintended side effects:

  https://issues.guix.gnu.org/61841

I fixed it with:

  a516a0ba93 gexp: computed-file: Do not honor %guile-for-build.
  fee1d08f0d pack: Make sure tests can run without a world rebuild.

Please take a look.

We should think about how to improve our processes to avoid such issues
in the future.  I did raise concerns about this very patch late at night
during FOSDEM, 24h after submission, and reaffirmed my viewpoint days
later.  I understand that delaying a nice patch series like this one is
unpleasant, but I think those concerns should have been taken into
account.

Ludo’.