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run code in 200+ php & hhvm versions
Bugs & Features
<?php function bar($a){} function foo(&$a){ var_dump($a); } bar($b); foo($b); $c = &$d; var_dump($c);
based on qOAVi
Output for 5.0.4 - 7.2.0
Notice: Undefined variable: b in /in/jY8JO on line 6 NULL NULL
Output for 4.3.0 - 5.0.3
Notice: Undefined variable: b in /in/jY8JO on line 6 NULL NULL