This is a bug with WP 3.4 – I’ve posted a ticket ( you want to fix it right now, go into functions.php (in /wp-includes/) and on line 3625 you change

$trace = debug_backtrace( false ); to $trace = debug_backtrace();

It will solve your problems for the time being. Also, tell your host to update the PHP-version the server is running (it is because the old version that this error occurs).


Fix From Here: