Description:
------------
When using same variable with reference and without reference in foreach works incorrectly.

Test script:
---------------
$data = [
    [1, 2, 3],
    [4, 5, 6],
    [7, 8, 9]
];

foreach($data as $k => &$v) {
    rsort($v);
}

foreach($data as $k => $v) {
    print_r($v);
}

Expected result:
----------------
Array
(
    [0] => 3
    [1] => 2
    [2] => 1
)
Array
(
    [0] => 6
    [1] => 5
    [2] => 4
)
Array
(
    [0] => 6
    [1] => 5
    [2] => 4
)

Actual result:
--------------
Array
(
    [0] => 3
    [1] => 2
    [2] => 1
)
Array
(
    [0] => 6
    [1] => 5
    [2] => 4
)
Array
(
    [0] => 9
    [1] => 8
    [2] => 7
)