Description:
------------
Tested this on my custom built 5.3.8 and the standard 5.3.8 that ships with FC 15 - same result in both so I assume it is not specific to my build.  Run the test code - it will segfault.  Not sure if this is PHP related (PHP hooks into PCRE) or solely lives inside PCRE.

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

$input = "
................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. ................................................................................................................................................................................................. .................................................................................................................................................................................................
";
echo preg_replace('/(\.\s?){3,}/', '...', $input);

Expected result:
----------------
Not to dump core

Actual result:
--------------
Dumped core