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<?php $a = array(3, 4); $b =& $a[0]; $c = $a; var_dump($a); $c[0] = 5; var_dump($a); unset($b); $c[0] = 6; var_dump($a);
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 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, 7.1.0 - 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 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
array(2) { [0]=> &int(3) [1]=> int(4) } array(2) { [0]=> &int(5) [1]=> int(4) } array(2) { [0]=> &int(6) [1]=> int(4) }

preferences:
256.11 ms | 406 KiB | 367 Q