3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $test = array(1,9,3,5,1,5,3); usort(function ($a, $b){ return $a - $b; }, $test); ?>
Output for 5.3.0 - 5.4.24
Fatal error: Only variables can be passed by reference in /in/MPXCK on line 5
Process exited with code 255.