Fatal error: Uncaught Error: Class "Symfony\Component\Serializer\Exception\RuntimeException" not found in I:\www\frameworks\Symfony\doctrine\vendor\symfony\serializer\Exception\CircularReferenceException.php:19 Stack trace: #0 {main} thrown in I:\www\frameworks\Symfony\doctrine\vendor\symfony\serializer\Exception\CircularReferenceException.php on line 19