;; replacement character, so we hardcode the preferred
;; replacement here.
#\?
- (mb-char-len (or (,ucs-to-mb (char-code byte)) -1))
+ (block size
+ (mb-char-len (or (,ucs-to-mb (char-code byte))
+ (return-from size 0))))
(let ((mb (,ucs-to-mb bits)))
(if (null mb)
(external-format-encoding-error stream byte)