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run code in 200+ php & hhvm versions
Bugs & Features
<?php function foo(&$x) { $x = 123; } foo($bar = null); var_dump($bar);
Output for 7.0.0 - 7.3.1
Notice: Only variables should be passed by reference in /in/PdME1 on line 6 NULL
Output for 5.1.2 - 5.6.28
Strict Standards: Only variables should be passed by reference in /in/PdME1 on line 6 NULL
Output for 4.3.0 - 5.1.1
int(123)