Another instance of overlay problems

[Gerd Moellmann]

In GNU Emacs 21.3.50.1 (i386-unknown-freebsd4.8, X toolkit, Xaw3d scroll bars)
 of 2003-08-17

Emacs looped infinitely in recenter_overlay_lists because the
overlays_before list had a cycle.

#6  0x80efbbe in recenter_overlay_lists (buf=0x884a408, pos=961229)
    at buffer.c:3234
3234                  if (OVERLAY_POSITION (otherend) <= where)

(gdb) p buf->name
$26 = 948351644
(gdb) pr
"*shell*"
(gdb) p buf->text->z
$27 = 961229
(gdb) p pos
$28 = 961229

(gdb) p buf->overlays_before
$22 = (struct Lisp_Overlay *) 0x86c96b4
(gdb) p buf->overlays_before->next
$23 = (struct Lisp_Overlay *) 0x86c96b4

(gdb) p buf->overlays_after
$24 = (struct Lisp_Overlay *) 0x88905b0
(gdb) p buf->overlays_after->next
$25 = (struct Lisp_Overlay *) 0x0

(gdb) xbacktrace
"move-overlay"
"show-paren-function"
"apply"
"byte-code"
"timer-event-handler"

Don't know what the last input was, because I forgot to print it
before I closed the session :/.