bug#15605: 24.3.50; `mouse-drag-region' -> (error "Marker does not point anywhere")

[Drew Adams]

Not from emacs -Q.  And I'm not sure this will be any help.
But just in case it helps...

I didn't think that I used `mouse-1' at all, but apparently I did.  It
seems to me that I was using the mouse to resize a tiny frame that shows
*info*, but I could be mistaken.  Perhaps the mouse was on the mode line
instead of on the frame border?

Debugger entered--Lisp error: (error "Marker does not point anywhere")
  pop-mark()
  mouse-drag-track((down-mouse-1 (#<window 0529a1b0 on *info*<3>> 2256045 (181 
. 173) 80521585 nil 2256045 (22 . 13) nil (5 . 5) (8 . 14))) t)
  mouse-drag-region((down-mouse-1 (#<window 0529a1b0 on *info*<3>> 2256045 (181 
. 173) 80521585 nil 2256045 (22 . 13) nil (5 . 5) (8 . 14))))
  call-interactively(mouse-drag-region nil nil)
  command-execute(mouse-drag-region)

In GNU Emacs 24.3.50.1 (i686-pc-mingw32)
 of 2013-10-09 on LEG570
Bzr revision: 114596 jan.h.d@swipnet.se-20131009185014-vynfyw4o8p5fge54
Windowing system distributor `Microsoft Corp.', version 6.1.7601
Configured using:
 `configure --enable-checking 'CFLAGS=-O0 -g3' CPPFLAGS=-DGLYPH_DEBUG=1'