gnus bug when editing?

gnus bug when editing?

[Stefan Waldherr]

Hi,

I recently observed the following bug: select an article, hit `e' to edit,
edit something, then `C c' to finish. Selecting another article yields

(85) (warning/warning) Error caught in `font-lock-pre-idle-hook'

in the message line. Debug output is 

Signaling: (wrong-type-argument extent-live-p #<destroyed extent>)
  extent-start-position(#<destroyed extent>)
  font-lock-after-change-function(1 1 2111)
  erase-buffer()
  gnus-request-article-this-buffer(91 "nnml:timm")
  gnus-article-prepare(91 nil)
  gnus-summary-display-article(91 nil)
  gnus-summary-select-article(nil nil pseudo)
  gnus-summary-scroll-up(1)
  call-interactively(gnus-summary-scroll-up)

Anyone?

Thanks,
Stefan.
-- 
Stefan Waldherr                   fax +49 431 8058 136
                               e-Mail swa@cs.cmu.edu
                                  www http://www.waldherr.org/

XEmacs bug? [was Re: gnus bug when editing?]

[Jan Vroonhof]

Stefan Waldherr <swa@cs.cmu.edu> writes:

> I recently observed the following bug: select an article, hit `e' to edit,
> edit something, then `C c' to finish. Selecting another article yields
> 
> (85) (warning/warning) Error caught in `font-lock-pre-idle-hook'

I cannot reproduce this with 21.x, but I think I can see what the problem is.

> Signaling: (wrong-type-argument extent-live-p #<destroyed extent>)
>   extent-start-position(#<destroyed extent>)
>   font-lock-after-change-function(1 1 2111)

It is a bug in the XEmacs font-lock-pre-idle-hook, does this "obviously
correct"  patch help:

1998-07-22  Jan Vroonhof  <vroonhof@math.ethz.ch>

	* font-lock.el (font-lock-fontify-glumped-region): Add guard
	aginst destroyed extents


Index: font-lock.el
===================================================================
RCS file: /usr/CVSroot/XEmacs/xemacs-20/lisp/font-lock.el,v
retrieving revision 1.7
diff -u -u -r1.7 font-lock.el
--- font-lock.el	1998/06/20 00:58:20	1.7
+++ font-lock.el	1998/07/22 16:29:22
@@ -1073,8 +1073,9 @@
   ;; region as fontified; otherwise, the same error might get signaled
   ;; after every command.
   (unwind-protect
-      ;; buffer may be deleted.
-      (if (buffer-live-p (extent-object font-lock-old-extent))
+      ;; buffer/extent may be deleted.
+      (if (and (extent-live-p font-lock-old-extent)
+	       (buffer-live-p (extent-object font-lock-old-extent)))
 	  (save-excursion
 	    (set-buffer (extent-object font-lock-old-extent))
 	    (font-lock-after-change-function-1