Description:
------------
Hello

I have a PHP warning with ArrayIterator when used with references.
Thank you for looking at this.


My test scripts works as expected if you replace 'cast($b)' by '$b = (int)$b'

Test script:
---------------
<?php
function cast(&$a) {
	$a = (int)$a;
}

$a = new ArrayIterator;
$a[-1] = 123;

$b = "-1";
cast($b);

echo $a[$b];
?>

Expected result:
----------------
123

Actual result:
--------------
PHP Warning:  Illegal offset type in /tmp/test.php on line 12