diff --git a/kernel/mutex.h b/kernel/mutex.h
index aeb2d91..a075daf 100644
--- a/kernel/mutex.h
+++ b/kernel/mutex.h
@@ -22,7 +22,7 @@
 #define debug_mutex_free_waiter(waiter)			do { } while (0)
 #define debug_mutex_add_waiter(lock, waiter, ti)	do { } while (0)
 #define debug_mutex_unlock(lock)			do { } while (0)
-#define debug_mutex_init(lock, name)			do { } while (0)
+#define debug_mutex_init(lock, name, key)		do { } while (0)
 
 static inline void
 debug_mutex_lock_common(struct mutex *lock, struct mutex_waiter *waiter)