bug#32593: bad error message when kernel module does not exist

[ludo@gnu.org (Ludovic Courtès)]

Hello,

Ricardo Wurmus <rekado@elephly.net> skribis:

> When a system is built that requests a kernel module that does not
> exists, this is the error message a user will see:
>
> Backtrace:
>            8 (primitive-load "/gnu/store/vz7ci9rh483f2zps2cl174rd91b?")
> In ice-9/eval.scm:
>     619:8  7 (_ #f)
>    626:19  6 (_ #<directory (guile-user) 7cf140>)
>     159:9  5 (_ _)
> In gnu/build/linux-modules.scm:
>    184:47  4 (recursive-module-dependencies _ #:lookup-module _)
>     98:14  3 (module-dependencies _)
>     85:18  2 (modinfo-section-contents _)
> In ice-9/ports.scm:
>    439:11  1 (call-with-input-file #f #<procedure get-bytevector-al?> ?)
> In unknown file:
>            0 (open-file #f "r" #:encoding #f #:guess-encoding #f)
>
> ERROR: In procedure open-file:
> Wrong type (expecting string): #f
> builder for `/gnu/store/0ahsvp7wx52zzh1rywbdbq78llcwb7id-linux-modules.drv' failed with exit code 1

This project is incredible: the bug was fixed even before you had
reported it, in commit 4db7a9dc663c5b26e45ec35538bf68ff87acdf7b.  :-)

You still get a backtrace, but at least the error message is somewhat
clearer.  (Should we do away with the backtrace?)

Ludo’.