3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php function foo(&$v){ $v++; } $a = 0; $b = 1; foo($a); foo($a = $b);
Output for 7.0.0 - 7.2.0
Notice: Only variables should be passed by reference in /in/6v9hh on line 11
Output for 5.1.0 - 5.6.28
Strict Standards: Only variables should be passed by reference in /in/6v9hh on line 11
Output for 4.3.2 - 4.4.0, 5.0.0 - 5.0.5
Fatal error: Only variables can be passed by reference in /in/6v9hh on line 11
Process exited with code 255.
Output for 4.4.1 - 4.4.9
Notice: Only variables can be passed by reference in /in/6v9hh on line 11
Output for 4.3.0 - 4.3.1
Fatal error: Only variables can be passed by reference in /in/6v9hh on line 11