3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php function bar($a){} function foo(&$a){ var_dump($a); } foo($b); bar($a);
based on iHj91
Output for 5.0.4 - 7.2.0
NULL Notice: Undefined variable: a in /in/iGt6F on line 7
Output for 4.3.0 - 5.0.3
NULL Notice: Undefined variable: a in /in/iGt6F on line 7