bug#33623: Backtrace when running `guix system roll-back'

[Diego Nicola Barbato <dnbarbato@posteo.de>]

Diego Nicola Barbato <dnbarbato@posteo.de> writes:

> Hello Swedebugia,
>
> swedebugia@riseup.net writes:
>
>> On 2018-12-05 12:36, Diego Nicola Barbato wrote:
>>> Hello Guix,
>>> 
>>> When I run ‘guix system roll-back’ I get the following backtrace:
>>> 
>>> --8<---------------cut here---------------start------------->8---
>>> root@tapuakh ~# guix system roll-back
>>> Backtrace:
>>>           10 (primitive-load "/root/.config/guix/current/bin/guix")
>>> In guix/ui.scm:
>>>   1603:12  9 (run-guix-command _ . _)
>>> In ice-9/boot-9.scm:
>>>     829:9  8 (catch srfi-34 #<procedure 341ea60 at guix/ui.scm:615:…> …)
>>>     829:9  7 (catch system-error #<procedure 341eb00 at guix/script…> …)
>>> In guix/scripts/system.scm:
>>>    1268:8  6 (_)
>>> In guix/status.scm:
>>>     615:4  5 (call-with-status-report _ _)
>>> In guix/scripts/system.scm:
>>>    1208:9  4 (process-command _ _ _)
>>>    469:10  3 (switch-to-system-generation #<build-daemon 256.99 1ec…> …)
>>> In guix/store.scm:
>>>   1659:24  2 (run-with-store _ _ #:guile-for-build _ #:system _ # _)
>>> In guix/scripts/system.scm:
>>>     499:6  1 (_ _)
>>> In unknown file:
>>>            0 (_ #<build-daemon 256.99 1ec03c0>)
>>> 
>>> ERROR: Wrong type to apply: #<<computed-file> name: "grub.cfg" gexp:
>>> #<gexp  3971ab0> guile: #f options: (#:local-build? #t)>
>>> --8<---------------cut here---------------end--------------->8---
>>> 
>>> I run GuixSD (commit: 1f51f0d975d95a2ba645193cf43d0a294d952e83) on an
>>> x86_64 machine.
>>
>> Interesting. Could you provide a config.scm to help us reproduce the
>> issue?
>
> I've got something better.
>
> Steps to reproduce:
>
> Install GuixSD in a VM using the iso image and the attached config.  The
> image should be at least 16G (8G is to small for a reconfigure).
>
> Reboot the VM.
>
> Run ‘guix pull --commit=1f51f0’ as root.
>
> Make sure to log out and back in again to avoid bug#33647.
>
> Run ‘guix system reconfigure /etc/config.scm’.
>
> Reboot the VM.
>
> Run ‘guix system roll-back’ as root.
>
> Backtrace ensues.

I just repeated the aforementioned steps with the new (0.16.0) iso image
and by pulling from current master (5118e2) instead of 1f51f0 and got a
similar backtrace.  I believe ‘guix system roll-back’ is currently
broken on master.
Judging from the backtrace this might have something to do with the
recent clean up of system code (specifically commit 46c296).

Greetings

Diego