lib/modules: Fix missing prefix in extendModules when unset in both eval- and extend-

1 files changed, 1 insertions, 1 deletions

diff --git a/lib/modules.nix b/lib/modules.nix
index 0bbf9d43c575e..48ddb31508f25 100644
--- a/lib/modules.nix
+++ b/lib/modules.nix
@@ -350,7 +350,7 @@ rec {
           evalModules (evalModulesArgs // {
             modules = regularModules ++ modules;
             specialArgs = evalModulesArgs.specialArgs or {} // specialArgs;
-            prefix = extendArgs.prefix or evalModulesArgs.prefix;
+            prefix = extendArgs.prefix or evalModulesArgs.prefix or [];
             inherit extensionOffset;
           });