modification hooks called only once in c-mode

[Nikolaj Schumacher <n_schumacher@web.de>]

Hello,


occasionally modification hooks seem to be called only once in c-mode
(and derivatives).

This happens in both released and CVS version of Emacs 22, but not in
Emacs 21.


To reproduce, evaluate the following:

(defun test-bug-hook (overlay afterp beg end &optional r)
  (message "%s hook called" (if afterp "after" "before")))

(defun test-bug ()
  (let ((beg (point))
        ov)
    (insert "foobar")
    (setq ov (make-overlay beg (point)))
    (overlay-put ov 'face 'highlight)
    (overlay-put ov 'insert-in-front-hooks '(test-bug-hook))))


1) Create a new buffer in fundamental-mode, evaluate (test-bug), and
insert a char before the overlay.

Result:
before hook called
after hook called


1) Create a new buffer in c-mode, evaluate (test-bug), and insert a char
before the overlay.

Result:
before hook called


The hook is never called after the change.



In GNU Emacs 22.1.1 (i386-apple-darwin8.10.1, Carbon Version 1.6.0)
 of 2007-07-16 on wednesday
Windowing system distributor `Apple Inc.', version 10.4.10
configured using `configure  '--prefix=/Applications/Emacs.app/Contents/Resources' '--with-carbon' '--without-x' '--libexecdir=/Applications/Emacs.app/Contents/MacOS/libexec' 'CFLAGS=-arch i386 -isysroot /Developer/SDKs/MacOSX10.4u.sdk -DUSE_ATSUI -O2''


regards,
Nikolaj Schumacher