3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php function &foo() { static $a; return ++$a; } $a = &foo(); var_dump($a + $a + $a + $a);
Output for 5.6.0 - 7.1.0
Notice: Only variable references should be returned by reference in /in/2IZRv on line 5 int(4)
Output for 4.3.0 - 5.5.38
int(4)