bug#41237: guix deploy hangs when a file-system-device is set to a UUID

[Maxim Cournoyer <maxim.cournoyer@gmail.com>]

Hello Brice and Ludovic,

Ludovic Courtès <ludo@gnu.org> writes:

> Hi Brice,
>
> Brice Waegeneire <brice@waegenei.re> skribis:
>
>> scheme@(guix-user) [1]> ,up
>> In gnu/system/uuid.scm:
>>      302:5  3 (uuid=? . _)
>> scheme@(guix-user) [1]> ,locals
>>    Local variables:
>>    $8 = closure = #<procedure uuid=? expr>
>>    $9 = w = #vu8(185 176 222 181)
>> While executing meta-command:
>> In procedure frame-local-ref: Argument 2 out of range: 3
>> scheme@(guix-user) [1]> ,up
>>             4 (find #<procedure 7f9a930bd570 at 
>> gnu/build/file-systems.scm:606:4 (device)> ("/dev/sda" "/dev/sda1" 
>> "/dev/sda2" "/dev/sda3" "/dev/sdb" "/dev/sdb2" "/dev/sdb3"))
>
> So all we can say, is that one of the “partition readers” in (gnu build
> file-systems) hangs while reading from one of these.
>
> I don’t have good advice other than trying to run the code by hand to
> find out which device/reader pair causes the problem.
>
> I hope that makes sense.  We can further debug this on IRC if you want.
>
> Thanks,
> Ludo’.

Fixed with 0dd04b9986dd834782c988035569089785a6987d and
04a4af6dd4fbfcfc564eac5eafe647b192ba3a8f.  Thanks to Ludovic for the
pointers and both of you for recording the very useful above debugging
session.

Closing,

Maxim