diff --git a/src/engine.c b/src/engine.c
index cd3d05c09d54f54a4ed042c3c04ce0a0485c4fd5..75c25cdb8b5f0450deb6f05e4c896c6ebe24305a 100644
--- a/src/engine.c
+++ b/src/engine.c
@@ -2926,6 +2926,7 @@ void engine_prepare(struct engine *e) {
  * @brief Implements a barrier for the #runner threads.
  *
  * @param e The #engine.
+ * @param tid The thread ID
  */
 void engine_barrier(struct engine *e) {