Emacs crashes when killing region with overlays in it

[Michael Schierl]

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In GNU Emacs 21.3.1 (i386-msvc-nt5.0.2195)
 of 2003-03-28 on buffy
configured using `configure --with-msvc (12.00)'
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: iso-latin-1
  default-enable-multibyte-characters: t

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

Run an emacs - the emacs 21.3 on Windows (from where I send the
bug report) and the emacs 21.4 on Debian Sarge and the Unstable Emacs
on nqmacs.sf.net are affected - with emacs -q.

Then load a file containing

(let (ovl)
  (with-temp-buffer
    (insert "-\n<a\n-\n<b\n-\n<c\n-\n<d\n-")
    (mapc (lambda (pos)
            (setq ovl (make-overlay pos (1+ pos)))
            (overlay-put ovl 'after-string ">"))
          '(4 9 14 19))
    (switch-to-buffer (current-buffer))
    (sit-for 0)
    (kill-region 3 21)
    (sit-for 0)
))
 
and execute it with C-x C-e. On Windows you will get the usual
"program will be terminated" dialog, on Linux a "Segmentation fault"
is printed to the console.

This is some weird bug - I tried to make the sequence to reproduce it
more minimal, especially to remove the sit-for calls or reduce the
number of overlays, but I did not succeed. For some strange reason,
this bug sometimes (very rarely, it happened once to me) cannot be
reproduced when you already worked a lot in your Emacs, but when
starting up a fresh one, reproducing it works again.

Michael