bug#8047: 23.2.94; Auto image mode breaks C-x C-w

[Eli Zaretskii]

> From: Glenn Morris <rgm@gnu.org>
> Cc: monnier@iro.umontreal.ca,  cyd@stupidchicken.com,  8047@debbugs.gnu.org
> Date: Wed, 16 Feb 2011 23:34:43 -0500
> 
> Eli Zaretskii wrote:
> 
> >> You would need to make it buffer-local.
> >
> > ??? It's permanently local already, see its doc string.
> 
> If you test your proposed patch, you will find it sets the global value.

I tested it, just not deep enough ;-)

> It is permanently local, *once made buffer local*.

Turns out I had a fundamental misunderstanding of what "permanently
local" means.  The fact that the Elisp manual is silent about that
does not help.  Is there something beyond the fact that
kill-all-local-variables doesn't touch them, or is that all there is
to it?