bug#21732: 25.0.50; intermittent failure using windmove when in doc-view buffer

[martin rudalics]

> Sorry for the confusion. I do have `windmove-wrap-around' set to t, and this 
is
> with the frame split; i.e. when there is a different window to wrap around
> to. In that case (sorry for not being specific), other windows on the right 
side
> of the frame were wrapping around correctly, but the window viewing the 
doc-view
> buffer was not. Again, an intermittent error, so I'll try to provide a 
backtrace
> when it happens again.

Alternatively, you could try to add the function ‘window-in-direction’
(in window.el) temporarily to your .emacs.  There replace the line

           ((let ((posn-cons (nth 2 (posn-at-point (window-point window) 
window))))

by a form like

           ((let ((posn-cons (nth 2 (posn-at-point (window-point window) 
window))))
              (let ((my-value (cdr posn-cons)))
                (when (or (not my-value) (< my-value 0))
                  (setq my-variable
                        (cons
                         (format "window: %s direction : %s sign: %s wrap: %s mini: 
%s posn-cons: %s"
                                 window direction sign wrap mini posn-cons)
                         my-variable))))

and also add a definition like

(defvar my-variable nil)

to your .emacs.  When now a "No window right from selected window" error
triggers, look at the value of ‘my-variable’.  If it's non-nil, we might
have a clue.

Obviously you can make the above mentioned change also in-place, i.e. in
window.el, but don't forget to remake the emacs executable afterwards.

martin