bug#69401: /etc/guix/machines.scm symlink can be garbage collected

[Ludovic Courtès]

Ludovic Courtès <ludo@gnu.org> skribis:

> Ludovic Courtès <ludo@gnu.org> skribis:
>
>> root@hydra-guix-108 ~# guix gc -R $(readlink -f /run/current-system) |grep 
>> machines.scm
>> /gnu/store/xg26iis3ydik6zxqk24cyk7h9zli1d25-machines.scm
>> root@hydra-guix-108 ~# ls -l /etc/guix/machines.scm
>> lrwxrwxrwx 1 root root 56 Mar  7 11:53 /etc/guix/machines.scm -> 
>> /gnu/store/1171q4xhph07ll3mlzlg7igcwg3c98i1-machines.scm
>
> Turns out that both files are identical, but:
>
>   • /gnu/store/1171q4xhph07ll3mlzlg7igcwg3c98i1-machines.scm is built
>     with
>     /gnu/store/g8p09w6r78hhkl2rv1747pcp9zbk6fxv-guile-3.0.9/bin/guile
>     (‘guile-final’ ungrafted);
>
>   • /gnu/store/xg26iis3ydik6zxqk24cyk7h9zli1d25-machines.scm is built
>     with
>     /gnu/store/g49b4v7dff8xwfi7wpi8pps1ixhld3n7-guile-3.0.9/bin/guile
>     (‘guile-final’ grafted).
>
> As it turns out, <scheme-file> (used for “machines.scm”) uses
> ‘gexp->file’, which, unlike ‘gexp->script’, does not default to
> (default-guile).  That probably explains the difference.

I believe this is fixed by b30b838d5055e36be19d030db28838fec4474d98.

Ludo’.