diff --git a/nixos/modules/tasks/filesystems.nix b/nixos/modules/tasks/filesystems.nix
index 8581a31d2c8e..f98ef3304635 100644
--- a/nixos/modules/tasks/filesystems.nix
+++ b/nixos/modules/tasks/filesystems.nix
@@ -355,9 +355,7 @@ in
       }
       {
         assertion = ! (any (fs: fs.formatOptions != null) fileSystems);
-        message = let
-          fs = head (filter (fs: fs.formatOptions != null) fileSystems);
-        in ''
+        message = ''
           'fileSystems.<name>.formatOptions' has been removed, since
           systemd-makefs does not support any way to provide formatting
           options.