diff --git a/stubs/Stringable.php b/stubs/Stringable.php
index 48afc3af7ba..29a3f6f618f 100644
--- a/stubs/Stringable.php
+++ b/stubs/Stringable.php
@@ -2,5 +2,6 @@
 
 interface Stringable
 {
-    function __toString() : string;
+    /** @return string */
+    function __toString();
 }