3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $x = array(10); $x[1] = &$x[0]; $x[0]++; var_dump($x);
Output for 4.3.0 - 7.2.0
array(2) { [0]=> &int(11) [1]=> &int(11) }