Crash when having malformed PBM image on screen and viewing *Messages* buffer (on Windows)

[Michael Schierl]

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 bug-gnu-emacs@gnu.org mailing list,
and to the gnu.emacs.bug news group.

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



It was a bit hard to reproduce. In fact, I tried to make up a valid xbm
:data chunk, and failed (any hints for a working example
appreciated...), because my Emacs crashed too often.

There are lots of ways to crash Emacs (just work with it for a while
while there are lots of broken xbm images in your buffer), but here is a
reproducable one:


- start emacs -Q
- run this in *scratch* buffer

(progn
  (put-image '(image :type pbm :data "") 0)
  (pop-to-buffer "*Messages*")
  (goto-char (point-max)))

Now press <down> <right> <down> <right>.

When Emacs asks you whether you want to attach a debugger, answer
whatever you find appropriate :)

Sorry, no gdb available here, but I guess this is pretty reproducable
for those who have one.


In GNU Emacs 22.1.1 (i386-mingw-nt5.1.2600)
 of 2007-06-02 on RELEASE
Windowing system distributor `Microsoft Corp.', version 5.1.2600
configured using `configure --with-gcc (3.4) --cflags -Ic:/gnuwin32/include'

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: DEU
  locale-coding-system: cp1252
  default-enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:
  encoded-kbd-mode: t
  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
  unify-8859-on-encoding-mode: t
  utf-translate-cjk-mode: t
  auto-compression-mode: t
  line-number-mode: t

Recent input:
M-x r e p o r t <tab> <return>

Recent messages:
("D:\\Progs\\emacs\\bin\\emacs.exe" "-Q")
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