(define (make-crc-table)
  (map (lambda (n)
         (let ((c n))
           (for-each (lambda (k)
                       (if (fxand c 1)
                           (set! c (fxxor #xedb88320 (fxshr c 1)))
                           (set! c (fxshr c 1))))
                     (iota 8))
           c))
       (iota 256)))

; Why does this give different results for each call?