diff --git a/Caster/Caster.php b/Caster/Caster.php
index cd9b35f7..b6a84fcb 100644
--- a/Caster/Caster.php
+++ b/Caster/Caster.php
@@ -115,7 +115,7 @@ public static function castObject(object $obj, string $class, bool $hasDebugInfo
      * @param array    $a                The array containing the properties to filter
      * @param int      $filter           A bit field of Caster::EXCLUDE_* constants specifying which properties to filter out
      * @param string[] $listedProperties List of properties to exclude when Caster::EXCLUDE_VERBOSE is set, and to preserve when Caster::EXCLUDE_NOT_IMPORTANT is set
-     * @param int      &$count           Set to the number of removed properties
+     * @param int|null &$count           Set to the number of removed properties
      */
     public static function filter(array $a, int $filter, array $listedProperties = [], ?int &$count = 0): array
     {
diff --git a/Caster/ReflectionCaster.php b/Caster/ReflectionCaster.php
index 591751fc..4adb9bc9 100644
--- a/Caster/ReflectionCaster.php
+++ b/Caster/ReflectionCaster.php
@@ -322,7 +322,7 @@ public static function castParameter(\ReflectionParameter $c, array $a, Stub $st
         if ($c->isOptional()) {
             try {
                 $a[$prefix.'default'] = $v = $c->getDefaultValue();
-                if ($c->isDefaultValueConstant()) {
+                if ($c->isDefaultValueConstant() && !\is_object($v)) {
                     $a[$prefix.'default'] = new ConstStub($c->getDefaultValueConstantName(), $v);
                 }
                 if (null === $v) {