3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php function f(&$x) {echo $x;} function g() {return 2;} $x = 1; f(1); echo $x;
Output for 5.3.0 - 5.4.21
Fatal error: Only variables can be passed by reference in /in/OKcJR on line 5
Process exited with code 255.