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<?php $x = 4; $y = &$x; $a = [1,2,$y]; $b = $a; $b[2] = 40; var_dump($a); var_dump($b);
Output for 7.1.25 - 7.1.33, 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.27, 8.4.1 - 8.4.14
array(3) { [0]=> int(1) [1]=> int(2) [2]=> int(4) } array(3) { [0]=> int(1) [1]=> int(2) [2]=> int(40) }

preferences:
149.98 ms | 408 KiB | 5 Q