anchor.diff:  (defconstant +location-type-signed-byte-64+   8)
   (defconstant +location-type-single-float+     9)
   (defconstant +location-type-double-float+     10)
  +(defconstant +location-type-short-float+      11)
   
   (defun sys.int::%instance-layout (object)
     "Return an instance's direct layout."
  
positive.code:     (#.+location-type-single-float+
       'sys.int::%object-ref-single-float-unscaled)
      (#.+location-type-double-float+
       'sys.int::%object-ref-double-float-unscaled)))
  )
  
  (macrolet ((def (name-base args)
  
negative.code:     #.+location-type-signed-byte-32+
      #.+location-type-signed-byte-64+
      #.+location-type-single-float+
      #.+location-type-double-float+
      #.+location-type-short-float+))
  
  (defun make-location (type offset)
    (logior (dpb type +location-type+ 0)
  