bug#1654: 23.0.60; auto encoding detection (detect-coding-region) not working

[Gaofeng Huang]

Please write in English if possible, because the Emacs maintainers
usually do not have translators to read other languages for them.

Your bug report will be posted to the emacs-pretest-bug@gnu.org mailing list.

Please describe exactly what actions triggered the bug
and the precise symptoms of the bug:


The auto encoding detection can not detect the correct encoding (for
example, for the two files attached). And neither the
detect-coding-region function works (after M-x find-file-literally)

File: 08-jj_lin-street-tosk.mp3
Title:   街道                           Track: 8
Artist:  林俊傑
Album:   陸                             Year:  2008

File: 08-jj_lin-street-tosk.mp3
Title:   街道                           Track: 8
Artist:  林俊傑
Album:   陸                             Year:  2008



If Emacs crashed, and you have the Emacs process in the gdb debugger,
please include the output from the following gdb commands:
    `bt full' and `xbacktrace'.
If you would like to further debug the crash, please read the file
/Applications/Emacs.app/Contents/Resources/etc/DEBUG for instructions.


In GNU Emacs 23.0.60.1 (i386-apple-darwin9.5.0, NS apple-appkit-949.35)
 of 2008-12-11 on neutron.local
Windowing system distributor `Apple', version 
97.112.112.108.101.45.97.112.112.107.105.116.45.57.52.57.46.51.53
configured using `configure  '--with-ns''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: zh_CN.UTF-8
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: nil
  value of $XMODIFIERS: @im=fcitx
  locale-coding-system: utf-8-unix
  default-enable-multibyte-characters: t

Major mode: Group

Minor modes in effect:
  erc-log-mode: t
  erc-list-mode: t
  erc-menu-mode: t
  erc-autojoin-mode: t
  erc-ring-mode: t
  erc-networks-mode: t
  erc-pcomplete-mode: t
  erc-track-mode: t
  erc-track-minor-mode: t
  erc-match-mode: t
  erc-button-mode: t
  erc-fill-mode: t
  erc-stamp-mode: t
  erc-netsplit-mode: t
  erc-irccontrols-mode: t
  erc-noncommands-mode: t
  erc-move-to-prompt-mode: t
  erc-readonly-mode: t
  gnus-undo-mode: t
  iswitchb-mode: t
  recentf-mode: t
  which-function-mode: t
  show-paren-mode: t
  mouse-sel-mode: t
  global-hl-line-mode: t
  pinbar-mode: t
  shell-dirtrack-mode: t
  tooltip-mode: t
  tool-bar-mode: t
  mouse-wheel-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  global-auto-composition-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
g i p SPC r y m SPC DEL r t f p SPC v b SPC b SPC . 
RET w q SPC j SPC i SPC j SPC e t SPC r SPC h j SPC 
t h g c SPC s g SPC ? RET ESC 1 C-c C-@ C-c C-@ C-l 
ESC 1 p ESC x u n i TAB c TAB TAB - v TAB RET C-n C-n 
C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-x C-f ESC 
p RET C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n 
C-n C-n C-n C-n C-x k C-x b & RET ESC 1 C-c C-@ DEL 
DEL DEL DEL DEL DEL DEL DEL DEL DEL DEL DEL DEL DEL 
DEL DEL DEL C-l C-l C-l C-l DEL DEL ESC 1 ESC x n e 
w s C-p C-p RET U N o o o o o o ESC x n e w s C-p C-p 
RET ESC 1 C-p C-p C-p C-p C-p C-p C-p C-p C-p C-p C-p 
C-p C-p C-p C-p C-p C-p C-p C-p C-p C-p C-p C-p C-p 
C-x C-f ~ / t e s t _ g b k TAB RET C-x k C-x C-f ESC 
p C-g ESC x u n i c a TAB - d i s TAB RET C-x C-f ESC 
p RET C-x k C-x C-f ESC p ESC DEL ESC DEL b i g TAB 
RET C-x k ESC x ESC p C-e ESC DEL e n TAB RET C-x C-f 
ESC p RET C-x k C-x C-f ESC p ESC DEL ESC DEL g b k 
TAB RET C-x k C-n C-n C-n C-n C-n C-n C-n C-n C-p ESC 
x r e p o TAB r TAB RET

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