Merge from origin/emacs-24

[gnu-emacs] / lisp / emacs-lisp / debug.el

diff --git a/lisp/emacs-lisp/debug.el b/lisp/emacs-lisp/debug.el
index 83213285d4e93e6719bbf41d011687b6065a9e1d..ce5c7863c3cd64ad83daa149ea3895f3b8858fbd 100644 (file)
--- a/lisp/emacs-lisp/debug.el
+++ b/lisp/emacs-lisp/debug.el
@@ -192,8 +192,10 @@ first will be printed into the backtrace buffer."
               debugger-buffer
               `((display-buffer-reuse-window
                  display-buffer-in-previous-window)
-                 . (,(when debugger-previous-window
-                       `(previous-window . ,debugger-previous-window)))))
+                . (,(when (and (window-live-p debugger-previous-window)
+                               (frame-visible-p
+                                (window-frame debugger-previous-window)))
+                      `(previous-window . ,debugger-previous-window)))))
              (setq debugger-window (selected-window))
              (if (eq debugger-previous-window debugger-window)
                  (when debugger-jumping-flag