[bug#41924] [PATCH] profiles: Make linux-module-database skip inappropriate inputs

[Ivan Kozlov <kanichos@yandex.ru>]

This allows a Linux package with CONFIG_MODULES=n, that doesn’t contain the ‘lib/modules’ directory, to be used.

* guix/profiles.scm (linux-module-database): Add if clause to ignore unrelated inputs. Allow empty result.
---
 guix/profiles.scm | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/guix/profiles.scm b/guix/profiles.scm
index 25ff146bdf..a3868e8343 100644
--- a/guix/profiles.scm
+++ b/guix/profiles.scm
@@ -1220,9 +1220,11 @@ This is meant to be used as a profile hook."
                        inputs))
                  (directory-entries
                   (lambda (directory)
-                    (scandir directory (lambda (basename)
-                                         (not
-                                           (string-prefix? "." basename))))))
+                    (if (file-exists? directory)
+                        (scandir directory (lambda (basename)
+                                             (not
+                                              (string-prefix? "." basename))))
+                        '())))
                  ;; Note: Should usually result in one entry.
                  (versions (delete-duplicates
                             (append-map directory-entries
@@ -1233,6 +1235,8 @@ This is meant to be used as a profile hook."
                   (setenv "PATH" #+(file-append kmod "/bin"))
                   (make-linux-module-directory inputs version #$output)
                   (setenv "PATH" old-path)))
+               ;; Do nothing when there is nothing to do
+               (() (mkdir #$output))
                (_ (error "Specified Linux kernel and Linux kernel modules
 are not all of the same version")))))))
   (gexp->derivation "linux-module-database" build
-- 
2.26.2