Mathieu Othacehe <othacehe@gnu.org> writes:

> Now there are multiple unclear points to me:
>
> 1. Why do we need an available machine with the foreign architecture to
> compute the corresponding "guix" derivation? Note that the evaluation of
> package derivations for foreign systems works even though a
> corresponding machine is not available:
>
> mathieu@berlin ~$ guix build -s powerpc64le-linux -d hello
> /gnu/store/spzmh79qi21k26p15w27r3jjg95szg17-hello-2.12.1.drv

This has been something I've been interested in as well, since the Guix
Data Service has the same problem when computing these derivations.

I think the latest information I have is set out here:

  https://lists.gnu.org/archive/html/guix-devel/2022-02/msg00196.html

So, I think there's some involvement of grafts that mean you end up
building things when just trying to compute the derivation. But that's
as far as I got, I don't really understand why this is the case, or what
can be done about it.

Chris