diff --git a/src/Type/TypehintHelper.php b/src/Type/TypehintHelper.php
index 333d9de4a7..5ae08aac5d 100644
--- a/src/Type/TypehintHelper.php
+++ b/src/Type/TypehintHelper.php
@@ -77,7 +77,7 @@ public static function decideTypeFromReflection(
 
 	public static function decideType(
 		Type $type,
-		?Type $phpDocType = null,
+		?Type $phpDocType,
 	): Type
 	{
 		if ($type instanceof BenevolentUnionType) {