No need to collect calls without params

There is no need to collect calls without parameters
as we only need the signature of the function and the code
will be generated when compiling the first file.

compiler/minils/transformations/callgraph_mapfold.ml

@@ -92,9 +92,12 @@ let node_by_longname ln =
     corresponding params (static parameters appear as free variables). *)
 let collect_node_calls ln =
   let add_called_node ln params acc =
-    match ln with
-      | Modname { qual = "Pervasives" } -> acc
-      | _ -> (ln, params)::acc
+    match params with
+      | [] -> acc
+      | _ ->
+          (match ln with
+            | Modname { qual = "Pervasives" } -> acc
+            | _ -> (ln, params)::acc)
   in
   let edesc funs acc ed = match ed with
     | Eapp ({ a_op = (Enode ln | Efun ln); a_params = params }, _, _) ->