- print_r: documentation ( source)
<?php
$date1 = new DateTime('2013-11-26T11:00:12');
$date2 = new DateTime('2004-11-26T23:59:59');
$date2 = DateTime::createFromFormat('YmdHis', '2004' . $date1->format('md') . '235959');
$diff = $date2->diff($date1);
print_r($diff);