Upgrade PHP to php7 X (III) failure of wechat payment callback

Today, the customer responded to the paid order , The system still shows unpaid
Look at the callback log file , It's empty
This is how callbacks in the original program get callbacks $xml = $GLOBALS['HTTP_RAW_POST_DATA'];
This cannot get content , Try this $xml = file_get_contents('php://input');
Sure enough ！！！