Bug 65349

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User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0; T312461; Q312461)

Description of problem:
[This is, IMO, an upstream bug, which I've reported a couple of times to the 
upstream maintainers, without any luck.]

If I use mouse-avoidance-fancy-hook in my post-command-hook, I sometimes get 
errors causing post-command-hook to be set to nil (most annoying). I think this 
is really due to a bug in mouse-avoidance-fancy-hook, but can't be bothered to 
dig it out, since it seems to cause no ill effects (and mouse-avoidance is 
purely a cosmetic thing).

I do have a fix: simply wrap mouse-avoidance-fancy-hook's body in(condition-
case nil ... (error nil)), i.e. ignore any errors generated inside it. I've 
been using this fix for months with no ill effects.

mouse-avoidance-fancy-hook is in xemacs-packages/lisp/edit-utils/avoid.el.

Version-Release number of selected component (if applicable):


How reproducible:
Always

Steps to Reproduce:
Actually reproducing the bug in normal use is tricky. Try something like:

1. Add mouse-avoidance-fancy-hook to your post-command-hook
2. Use XEmacs a lot, closing buffers from time to time (C-x k)
3. Eventually, you should get an error, caused by a position being out of 
range. I think it's because mouse-avoidance-fancy-hook is trying to examine 
part of a buffer that has just been killed. This will set post-command-hook to 
nil.


Actual Results:  post-command-hook was set to nil and I got an error

Expected Results:  Neither: it should Just Work (TM)

Additional info: