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run code in 150+ php & hhvm versions
Bugs & Features
<?php $x = array('hello'); $x[] = & $x; $y = unserialize(serialize($x)); $y[0] = 'world'; $x[0] = 'world'; var_dump($x); var_dump($y);
Output for 5.2.14 - 5.2.17, 5.3.3 - 5.6.28, 7.0.0 - 7.1.0
array(2) { [0]=> string(5) "world" [1]=> &array(2) { [0]=> string(5) "world" [1]=> *RECURSION* } } array(2) { [0]=> string(5) "world" [1]=> &array(2) { [0]=> string(5) "hello" [1]=> *RECURSION* } }
Output for hhvm-3.10.0 - 3.12.0
array(2) { [0]=> string(5) "world" [1]=> &array(2) { [0]=> string(5) "world" [1]=> *RECURSION* } } array(2) { [0]=> string(5) "world" [1]=> &array(2) { [0]=> string(5) "hello" [1]=> &array(2) { [0]=> string(5) "hello" [1]=> *RECURSION* } } }
Output for 5.1.0 - 5.2.13, 5.3.0 - 5.3.2
array(2) { [0]=> string(5) "world" [1]=> &array(2) { [0]=> string(5) "world" [1]=> &array(2) { [0]=> string(5) "world" [1]=> *RECURSION* } } } array(2) { [0]=> string(5) "world" [1]=> &array(2) { [0]=> string(5) "hello" [1]=> &array(2) { [0]=> string(5) "hello" [1]=> *RECURSION* } } }
Output for 4.3.0 - 5.0.5
array(2) { [0]=> string(5) "world" [1]=> array(2) { [0]=> string(5) "world" [1]=> *RECURSION* } } array(2) { [0]=> string(5) "world" [1]=> array(2) { [0]=> string(5) "hello" [1]=> NULL } }