diff --git a/CoAlgLogics.ml b/CoAlgLogics.ml
index 14d8d64bec674332da6ba830ecd977ade9fc31cf..a7d10c36eb4c2c8745325b23812b9ce74c5ba701 100644
--- a/CoAlgLogics.ml
+++ b/CoAlgLogics.ml
@@ -170,6 +170,8 @@ let mkRule_CL sort bs sl =
           C_i pairwise disjoint and I maximal
         }
   *)
+  (* just do this to let it compile... *)
+  mkRule_MultiModalK sort bs sl
 
 let mkRule_Choice sort bs sl =
   assert (List.length sl = 2);