diff --git a/clatd/main.c b/clatd/main.c
index f888041c0f..7aa1671339 100644
--- a/clatd/main.c
+++ b/clatd/main.c
@@ -37,7 +37,7 @@
 /* function: stop_loop
  * signal handler: stop the event loop
  */
-static void stop_loop() { running = 0; };
+static void stop_loop(__attribute__((unused)) int unused) { running = 0; };
 
 /* function: print_help
  * in case the user is running this on the command line