Description:
------------
Destructor has to be called on every attempt to release the object.

Test script:
---------------
class Registry {
  public static $v;
}

$v = new class() extends \stdClass {
  public function __destruct() {
    var_dump($this);
    Registry::$v = $this;
    echo 'destroyed' . "\n";
  }
};

unset($v);
var_dump(Registry::$v);
Registry::$v = null; // unset 2nd time

Expected result:
----------------
object(class@anonymous)#17 (0) {
}
destroyed
object(class@anonymous)#17 (0) {
}
object(class@anonymous)#17 (0) {
}
destroyed

Actual result:
--------------
object(class@anonymous)#17 (0) {
}
destroyed
object(class@anonymous)#17 (0) {
}