bug#2018: 23.0.60; Rmail buffer's encoding set incorrectly

[Eli Zaretskii <eliz@gnu.org>]

Start Rmail on an mbox file FOO with "C-u M-x rmail RET FOO RET", then
evaluate buffer-file-coding-system: you will see the value of
default-buffer-file-coding-system, instead of the encoding of the
message that is being displayed.

Type `p' and then `n' (to get to the same message): the value now
changes to undecided-unix.

Type "C-x C-s" (perhaps after making some changes, such as deleting a
message): the value changes to raw-text-dos.  Type `p' two times, and
the value changes back to undecided-unix.

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
d:/gnu/emacs/etc/DEBUG for instructions.


In GNU Emacs 23.0.60.1 (i386-mingw-nt5.1.2600)
 of 2009-01-24 on HOME-C4E4A596F7
Windowing system distributor `Microsoft Corp.', version 5.1.2600
configured using `configure --with-gcc (3.4)'

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: ENU
  value of $XMODIFIERS: nil
  locale-coding-system: cp1255
  default-enable-multibyte-characters: t

Major mode: RMAIL

Minor modes in effect:
  tooltip-mode: t
  tool-bar-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  global-auto-composition-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> O t h e r SPC <up> <left> SPC SPC <delete> 
<delete> <M-right> SPC ` = ' SPC c h a r a c t e r 
s SPC e l s e w h e r e SPC i n SPC t h e SPC b o d 
y SPC o f SPC t h e SPC p a r t i a l SPC m e s s a 
g e SPC a l s o SPC b e c o m e SPC e n c o d e d SPC 
i n SPC q u o t e d - p r i n t a b l e . M-q <up> 
<up> <down> <down> <right> <C-home> <down> <down> <C-right> 
<C-right> <C-right> <C-right> <C-right> <C-right> <C-right> 
<C-right> <right> r e - <C-right> C-k SPC q u o t e 
d - p r i n t a b l e SPC p a r t s <down> <down> <right> 
<up> <down> <up> <down> C-SPC <next> <down> <down> 
<down> <down> <down> <down> <down> <down> <down> <next> 
<down> <down> <down> <down> <down> <down> <down> <down> 
<down> <down> <down> <down> <down> <down> <down> <down> 
<down> <down> <down> <down> <down> <down> <down> <down> 
<next> <next> <next> <down> <down> <down> <down> <down> 
<down> <down> <down> <down> <down> <down> <down> <down> 
<down> <down> <down> <down> <down> <down> M-w <help-echo> 
<C-home> <down> <down> <C-right> <C-right> <C-right> 
<C-right> <right> <right> C-SPC C-e M-w <help-echo> 
<help-echo> <help-echo> C-x b <return> M-x <up> <up> 
<return>

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