too weird

[gnu-emacs-hacker]

In GNU Emacs 21.3.3 (i386-unknown-freebsd4.8, X toolkit, Xaw3d scroll bars)
 of 2003-06-08 on grant.org
Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: nil
  locale-coding-system: nil
  default-enable-multibyte-characters: t

$ emacs -q --no-site-file

Paste the code shown below and type <Control-X> <Control-E> to produce
the incorrect display shown below.  Now press <Return> and the missing
close-square-bracket character at the end of the buffer might just
appear.  Then again it might not.  It's hard to tell but it is more
than just a display bug as looking-at complains of that missing
close-square-bracket too, although not every time.

File Edit Options Buffers Tools Help
;; This buffer is for notes you don't want to save, and for Lisp evaluation.
;; If you want to create a file, visit that file with C-x C-f,
;; then enter the text in that file's own buffer.

(let* ((e "No error")
       (s '(133 2233))
       (r (concat "[" s "]")))
  (insert r)
  (condition-case err-var
      (looking-at r)
    (error (setq e (format "Error %S" err-var))))
  (message "%S %S %S %X %X %X\n%s" s r (length r)
           (aref r 0) (aref r 1) (aref r 2) e))



[\205?

----:**-F1  *scratch*         (Lisp Interaction)--L17--All------
"(133 2233) \"[\\205?]\" 3 5B 85 5D
No error"

Recent input:
SPC % S SPC % X SPC % X SPC % X % s " SPC s SPC r SPC 
( l e n g t h SPC r ) RET SPC SPC SPC SPC SPC SPC SPC 
SPC SPC SPC SPC ( a r e f SPC r SPC 0 ) SPC ( a r e 
f SPC r SPC 1 ) SPC ( a r e f SPC r SPC 2 ) SPC e ) 
) RET RET RET RET C-x C-e ESC x r e p o r t SPC e m 
SPC b u g RET

Recent messages:
(emacs -q --no-site-file)
For information about the GNU Project and its goals, type C-h C-p.
(133 2233) "[\205¹]" 3 5B 85 5D
No error
"(133 2233) \"[\\205¹]\" 3 5B 85 5D
No error"
Loading emacsbug...done