Description:
------------
Unsetting the last item of an array that has a numeric key updates the last used index of the array but the previous information is used when copying this array. Changing unset() to array_pop() produces the expected behaviour.

Test script:
---------------
<?php
// Output using xdebug
$ary = array('zero', 'one', 'two');
//array_pop($ary);
//array_pop($ary);
unset($ary[1]);
unset($ary[2]);
$bry = $ary;
$ary[] = 'three';
$bry[] = 'three';
var_dump($ary, $bry, $ary == $bry);
?>

Expected result:
----------------
array (size=2)
  0 => string 'zero' (length=4)
  1 => string 'three' (length=5)
array (size=2)
  0 => string 'zero' (length=4)
  3 => string 'three' (length=5)
boolean false

Actual result:
--------------
array (size=2)
  0 => string 'zero' (length=4)
  1 => string 'three' (length=5)
array (size=2)
  0 => string 'zero' (length=4)
  1 => string 'three' (length=5)
boolean true