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<?php error_reporting(E_ALL); function byref_function(&$a, &$b) { $a = 3; $b = 4; } $array = array(1, 2); call_user_func_array('byref_function', $array); var_dump($a, $b);
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Warning: byref_function(): Argument #1 ($a) must be passed by reference, value given in /in/4jNQ8 on line 11 Warning: byref_function(): Argument #2 ($b) must be passed by reference, value given in /in/4jNQ8 on line 11 Warning: Undefined variable $a in /in/4jNQ8 on line 13 Warning: Undefined variable $b in /in/4jNQ8 on line 13 NULL NULL
Output for 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33
Warning: Parameter 1 to byref_function() expected to be a reference, value given in /in/4jNQ8 on line 11 Warning: Parameter 2 to byref_function() expected to be a reference, value given in /in/4jNQ8 on line 11 Notice: Undefined variable: a in /in/4jNQ8 on line 13 Notice: Undefined variable: b in /in/4jNQ8 on line 13 NULL NULL
Output for 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20
Warning: Parameter 1 to byref_function() expected to be a reference, value given in /in/4jNQ8 on line 11 Notice: Undefined variable: a in /in/4jNQ8 on line 13 Notice: Undefined variable: b in /in/4jNQ8 on line 13 NULL NULL
Output for 5.0.4 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17
Notice: Undefined variable: a in /in/4jNQ8 on line 13 Notice: Undefined variable: b in /in/4jNQ8 on line 13 NULL NULL
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.3
Notice: Undefined variable: a in /in/4jNQ8 on line 13 Notice: Undefined variable: b in /in/4jNQ8 on line 13 NULL NULL

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212.57 ms | 402 KiB | 352 Q