diff --git a/src/util.c b/src/util.c
index 945262e..e65fd37 100644
--- a/src/util.c
+++ b/src/util.c
@@ -58,7 +58,7 @@ void PTHREAD_MUTEX_LOCK(pthread_mutex_t *x)
     }
 }
 
-void exit_failure()
+void exit_failure(void)
 {
     int nptrs;
     void *buffer[BT_BUF_SIZE];
diff --git a/src/util.h b/src/util.h
index 02d1442..fa4b679 100644
--- a/src/util.h
+++ b/src/util.h
@@ -46,7 +46,7 @@ void PTHREAD_MUTEX_UNLOCK(pthread_mutex_t *x);
 /**
  * \brief wrapper for exit(EXIT_FAILURE)
  */
-void exit_failure();
+void exit_failure(void);
 
 
 /**