run code in 200+ php & hhvm versions
Bugs & Features
<?php $t = 5; mul(&$t); function mul(&$t) { $t *= 5; } var_dump($t);

Here you find the average performance (time & memory) of each version. A grayed out version indicates it didn't complete successfully (based on exit-code).
Note: hhvm uses a JIT which only kicks in after a few runs. Since we run scripts only once, hhvm always runs slower.

VersionSystem time (s)User time (s)Memory (MiB)