anchor.diff:  (declaim (inline fill-buffer))
   (defun fill-buffer (reader)
     "Fills internal buffer of READER"
  -  (reset-counters reader)
     #+easy-audio-check-crc
     (setf (reader-crc reader)
           (funcall (reader-crc-fun reader)
  
positive.code: (declaim (inline can-not-read))
  (defun can-not-read (reader)
    "Checks if READER can be read without calling fill-buffer"
    (declare (type reader reader))
  
    (= (reader-ibyte reader)
       (reader-end reader)))
  
  
negative.code: (declaim (ftype (function (reader) (integer 0 1)) read-bit))
  (defun read-bit (reader)
    "Read a single bit from READER"
    (if (can-not-read reader) (fill-buffer reader))
  
    (prog1
  