diff --git a/mod/quiz/lib.php b/mod/quiz/lib.php
index 5680552cc768a..d1a33b483a449 100644
--- a/mod/quiz/lib.php
+++ b/mod/quiz/lib.php
@@ -473,6 +473,8 @@ function quiz_cron() {
         }
     }
     mtrace("Finished legacy quiz reports");
+
+    return true;
 }
 
 /**