diff --git a/src/counter.c b/src/counter.c
index cbee7b9..dace15f 100644
--- a/src/counter.c
+++ b/src/counter.c
@@ -75,7 +75,7 @@
 
 /*! Counts the registered counter
  *  \returns amount of counters */
-int osmo_counters_count()
+int osmo_counters_count(void)
 {
 	return llist_count(&counters);
 }