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<?php class A { public $b = false; function __construct($oB) { $this->b = $oB; } } class B { public $a = false; function __construct($oA) { $this->a = $oA; } } $aDepends = array(); $pLink = function() use (&$aDepends) { return $aDepends['A']; }; $oB = new B($pLink); $oA = new A($oB); $aDepends['A']=$oA; //$aDepends=$oA; //$oB->a = $oA; //var_dump($oA); //var_dump($oB); var_dump($oB->a);
Output for 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
object(Closure)#1 (1) { ["static"]=> array(1) { ["aDepends"]=> &array(1) { ["A"]=> object(A)#3 (1) { ["b"]=> object(B)#2 (1) { ["a"]=> *RECURSION* } } } } }

preferences:
175.7 ms | 404 KiB | 211 Q