3v4l.org

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<?php $callback = function & (&$a) { return $a; }; $a = (object) array(); $b = &$callback($a); $c = &call_user_func_array($callback, array(&$a)); var_dump($b === $a); var_dump($c === $a);
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.6 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
bool(true) bool(true)
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.28
Strict Standards: Only variables should be assigned by reference in /in/6dFIl on line 9 bool(true) bool(true)

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176.95 ms | 402 KiB | 219 Q