Description:
------------
I'm not sure, if this is a bug or a desired behaviour that is not mentioned in the docs. When merging an array with itself with array_merge() then modifiying one array element afterwards does also affect all other elements.

If it's intentional, then it should be mentionend in the documentation.

Test script:
---------------
<?php

$items = array();

$items[] = (object) array(
	'year' => 2012,
	'desc' => 'something happens'
);

$many = array_merge($items, $items);

print_r($many);

$many[0]->year = 2040;

print_r($many); // changes also year of $many[1]

Expected result:
----------------
$many[0]->year should be 2040
$many[1]->year should be 2012

Actual result:
--------------
$many[0]->year is 2040
$many[1]->year is 2040