Description:
------------
when i conert langer than 2147483647(0x6fffffff) use decbin will return 32's 1

Reproduce code:
---------------
<?php
$shmKey = ftok(__FILE__, 'c');
$pid    = posix_getpid();
if ($shmKey) {
>---$shmId = shmop_open($shmKey, 'c', 0775, 32);
>---$w     = shmop_write($shmId, 0x7fffffff, 0);
>---$r     = shmop_read($shmId, 0, 32);
>---$d     = shmop_delete($shmId);
>---echo $r . "\n";
>---echo decbin($r);
}
?>