3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php function a ($n){ return (b($n) * $n); } function b(&$n){ $n++; } var_dump(a(5));
Output for 4.3.0 - 5.6.28, hhvm-3.12.0, 7.0.0 - 7.1.0
int(0)
Output for hhvm-3.10.0

Process exited with code 153.