Description:
------------
Converting a stdClass object with (array) behaves different than get_object_vars()

I tested this with PHP 5.4.45 5.5.18 and 5.6.2

Test script:
---------------
$tmp = json_decode(json_encode(
    (object) array('cars' => (object) array("1" => "one"))
));

// expected $cars = array("1" => "one");
$cars = (array) $tmp->cars;

var_dump(array_key_exists("1", $cars)); // expected true, returns false
var_dump(array_key_exists(1, $cars)); // expected true, returns false

$cars = get_object_vars($tmp->cars);

var_dump(array_key_exists("1", $cars)); // expected true, returns true
var_dump(array_key_exists(1, $cars)); // expected true, returns true