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<?php function ref(&$a) {$a = 42;} function val($a) {$a = 42;} $val1 = 7; $val2 = 8; ref($val1); val($val2); var_dump([$val1, $val2]);
Output for 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 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
array(2) { [0]=> int(42) [1]=> int(8) }

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