bug#40839: Shepherd activation .GO files are not cross-compiled ... and the Hurd

[Mathieu Othacehe <m.othacehe@gmail.com>]

Hello Jan,

> /gnu/store/dbmj8ls2bwn0vbwi6qzng56rgrza3z0i-shepherd-host-name.go
> $ 11:27:25 janneke@dundal:~/src/guix/core-updates [env]
> $ file /gnu/store/dbmj8ls2bwn0vbwi6qzng56rgrza3z0i-shepherd-host-name.go
> /gnu/store/dbmj8ls2bwn0vbwi6qzng56rgrza3z0i-shepherd-host-name.go: ELF 64-bit LSB shared object no machine, version 1 (embedded), dynamically linked, with debug_info, not stripped

I strongly suspect this is because we would need to wrap the
"compile-file" call in "scm->go" procedure of (gnu services shepherd)
inside a "with-target".

That would look like:

--8<---------------cut here---------------start------------->8---
(if target
    (with-target target
                 (compile-file #$file #:output-file #$output
                               #:env env))
  (compile-file #$file #:output-file #$output
                #:env env))
--8<---------------cut here---------------end--------------->8---


Now, the tricky part is the value of target, because
#$(%current-target-system) might not be correct in that context.

Mathieu