id	summary	reporter	owner	description	type	status	priority	milestone	component	version	severity	resolution	keywords	cc
21650	replace serialize() with print_r() in stats() function in wp-includes/cache.php	bobbingwide		"In PHP 5.3 it is no longer possible to serialize data that contains a SimpleXMLElement object. It produces a fatal error. See https://bugs.php.net/bug.php?id=49800

The stats() function attempts to determine the allocated space for objects in the cache by using strlen() of the serialized object.

This can fail for the reason above.

Given that the figure returned is simply an estimation of the space 
I propose that the code is changed to use 
print_r( $cache, true ) instead of serialize( $cache )

ie. to become
`echo ""<li><strong>Group:</strong> $group - ( "" . number_format( strlen( print_r( $cache, true ) ) / 1024, 2 ) . 'k )</li>';`



This TRAC was raised after a longish chain of events starting with #18488 and the final response (today) which led to another chance discovery of a similar problem in the debug-bar plugin.

http://wordpress.org/support/topic/plugin-debug-bar-fatal-error-uncaught-exception-serialization-of-simplexmlelement-is-not-allowed



"	defect (bug)	new	normal	Awaiting Review	Cache	3.4.1	minor		has-patch