bug#18047: 24.4.50; Wrong type argument: arrayp, nil for `cua-mark-rectangle-mode'

[Drew Adams <drew.adams@oracle.com>]

emacs -Q

1. M-x load-library cua-rect.el

2. M-x set-variable debug-on-error t

3. Select text with the mouse, so its beginning and end are on different
   lines and columns (so they define a rectangle).

4. M-x cua-rectangle-mark-mode RET
   C-g

Repeat 3 & 4, selecting a different rectangle for 3.

You get this backtrace (or similar):

Debugger entered--Lisp error: (wrong-type-argument arrayp nil)
  aref(nil 6)
  (and (aref cua--rectangle 6))
  cua--rectangle-virtual-edges()
  (if (cua--rectangle-virtual-edges) " [R]" "")
  (setq cua--rectangle (if (and cua--last-rectangle (eq (car cua--last-rectangle) (current-buffer)) (eq (car (cdr cua--last-rectangle)) (point))) (cdr (cdr cua--last-rectangle)) (cua--rectangle-get-corners)) cua--status-string (if (cua--rectangle-virtual-edges) " [R]" "") cua--last-rectangle nil)
  cua--activate-rectangle()
  (progn (if (and reopen cua--last-rectangle (eq (car cua--last-rectangle) (current-buffer))) (goto-char (car (cdr cua--last-rectangle))) (if (not mark-active) (push-mark nil nil t))) (cua--activate-rectangle) (cua--rectangle-set-corners) (if cua-enable-rectangle-auto-help (cua-help-for-rectangle t)))
  (if (not cua--rectangle) (progn (if (and reopen cua--last-rectangle (eq (car cua--last-rectangle) (current-buffer))) (goto-char (car (cdr cua--last-rectangle))) (if (not mark-active) (push-mark nil nil t))) (cua--activate-rectangle) (cua--rectangle-set-corners) (if cua-enable-rectangle-auto-help (cua-help-for-rectangle t))))
  cua-set-rectangle-mark()
  (cond (cua-rectangle-mark-mode (add-hook (quote deactivate-mark-hook) (function (lambda nil (cua-rectangle-mark-mode -1)))) (add-hook (quote post-command-hook) (function cua--rectangle-post-command) nil t) (cua-set-rectangle-mark)) (t (cua--deactivate-rectangle) (remove-hook (quote post-command-hook) (function cua--rectangle-post-command) t)))
  (let ((last-message (current-message))) (setq cua-rectangle-mark-mode (if (eq arg (quote toggle)) (not cua-rectangle-mark-mode) (> (prefix-numeric-value arg) 0))) (cond (cua-rectangle-mark-mode (add-hook (quote deactivate-mark-hook) (function (lambda nil (cua-rectangle-mark-mode -1)))) (add-hook (quote post-command-hook) (function cua--rectangle-post-command) nil t) (cua-set-rectangle-mark)) (t (cua--deactivate-rectangle) (remove-hook (quote post-command-hook) (function cua--rectangle-post-command) t))) (run-hooks (quote cua-rectangle-mark-mode-hook) (if cua-rectangle-mark-mode (quote cua-rectangle-mark-mode-on-hook) (quote cua-rectangle-mark-mode-off-hook))) (if (called-interactively-p (quote any)) (progn nil (if (and (current-message) (not (equal last-message (current-message)))) nil (message "Cua-Rectangle-Mark mode %sabled" (if cua-rectangle-mark-mode "en" "dis"))))))
  cua-rectangle-mark-mode(toggle)
  funcall-interactively(cua-rectangle-mark-mode toggle)
  call-interactively(cua-rectangle-mark-mode record nil)
  command-execute(cua-rectangle-mark-mode record)
  execute-extended-command(nil "cua-rectangle-mark-mode")
  funcall-interactively(execute-extended-command nil "cua-rectangle-mark-mode")
  call-interactively(execute-extended-command nil nil)
  command-execute(execute-extended-command)

In GNU Emacs 24.4.50.1 (i686-pc-mingw32)
 of 2014-06-28 on ODIEONE
Bzr revision: 117431 rgm@gnu.org-20140628015517-eku6hj8mpgcvfnso
Windowing system distributor `Microsoft Corp.', version 6.1.7601
Configured using:
 `configure --prefix=3D/c/Devel/emacs/snapshot/trunk
 --enable-checking=3Dyes,glyphs 'CFLAGS=3D-O0 -g3'
 LDFLAGS=3D-Lc:/Devel/emacs/lib 'CPPFLAGS=3D-DGC_MCHECK=3D1
 -Ic:/Devel/emacs/include''