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<?php function wer(&$x) { echo $x; } $e = 'ert'; call_user_func('wer', $e);
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Warning: wer(): Argument #1 ($x) must be passed by reference, value given in /in/QT9Gd on line 6 ert
Output for 7.1.0 - 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
Warning: Parameter 1 to wer() expected to be a reference, value given in /in/QT9Gd on line 6 ert
Output for 7.0.0 - 7.0.20
Warning: Parameter 1 to wer() expected to be a reference, value given in /in/QT9Gd on line 6

preferences:
147.98 ms | 401 KiB | 183 Q