3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $a = "abcdef"; $a[-1];
Output for 4.3.0 - 5.3.29, 7.1.0 - 7.3.0rc4
Output for 5.4.0 - 7.0.20
Notice: Uninitialized string offset: -1 in /in/9FDhE on line 3