Description:
------------
This bug (http://bugs.php.net/bug.php?id=33635) reports the same php error but involves session handlers.

This bug (http://bugs.php.net/bug.php?id=33772) describes a possible reason this problem to be working as designed.

As reported bu the php team:

"This is chicken/egg problem and it cannot be solved. One expect that
destructors are called before session close the other uses object for
save handlers."

Are we to assume that a change has been made that is calling destructors before session close?  Fine, but why is this affecting register_shutdown? If register_shutdown() is part of the request, we expect to have access to the same scope.   Secondly why is this just affecting MySQLi?  Go ahead and reproduce the example code using MySQL and you'll see that it works as expected.

Reproduce code:
---------------
function shutdown()
{
	global $link;
	echo mysqli_real_escape_string($link, 'foo');
}

$servername = 'localhost';
$username = 'username';
$password = 'password';

$link = mysqli_init();
mysqli_real_connect($link, $servername, $username, $password);

echo mysqli_real_escape_string($link, 'foo') . '<br />';
register_shutdown_function('shutdown');

Expected result:
----------------
foo
foo

Actual result:
--------------
foo
Warning: Couldn't fetch mysqli in c:\program files\apache
group\Apache\htdocs\foo.php on line 7