3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $x = 0; $a = array(&$x); $b = $a; $x = 2; unset($x); $b[0]++; echo $a[0], ' ', $b[0];
based on XcCom
Output for 4.3.0 - 7.1.0
2 3