bug#6454: 24.0.50; kill-buffer switches current-buffer

[Helmut Eller <eller.helmut@gmail.com>]

* martin rudalics [2010-06-21 12:46+0200] writes:

>> Below are two patches.  The first essentially adds a save-excursion
>> around the whole function.
>>
>> The second patch adds a function run_hook_in_buffer. It iterates over
>> the functions in the hook and for each function explicitly sets the
>> buffer before calling it.  I had to introduce a new macro
>> DO_HOOK_FUNCTIONS which is a big hammer for this, but I couldn't find a
>> better way.
>
> Thanks.  I applied them here and will run them for a while to see
> whether and what they change.  BTW run_window_scroll_functions in
> xdisp.c has
>
>       run_hook_with_args_2 (Qwindow_scroll_functions, window,
> 			    make_number (CHARPOS (startp)));
>       SET_TEXT_POS_FROM_MARKER (startp, w->start);
>       /* In case the hook functions switch buffers.  */
>       if (current_buffer != XBUFFER (w->buffer))
> 	set_buffer_internal_1 (XBUFFER (w->buffer));
>
> so with your patch this is probably no more needed?
>
> Now, when a function run by a hook wants to change the current buffer it
> cannot do so any more.  Admittedly this was unreliable before so we
> probably won't lose much ...

My run_hook_in_buffer is (static) in buffer.c and only used by
Fkill_buffer.  The refactoring in eval.c was only needed to make it
possible to iterate over the functions of a hook.  It shouldn't affect
other things (modulo bugs that I introduced).

I guess unintended buffer switching could be a problem with many hooks,
but it's not clear if/when it's fix-worthy.

Helmut