Fixes: debbugs:18939

* simple.el (deactivate-mark): Only modify PRIMARY if we own PRIMARY.

2 files changed, 7 insertions, 1 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 8f888e37b06..7c7c66d24d6 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,8 @@
+2015-03-22  Jan Djärv  <jan.h.d@swipnet.se>
+
+        * simple.el (deactivate-mark): Only modify PRIMARY if we own
+        PRIMARY (Bug#18939).
+
 2015-03-22  Martin Rudalics  <rudalics@gmx.at>
 
         * emacs-lisp/debug.el (debug): Don't try using "previous" window
diff --git a/lisp/simple.el b/lisp/simple.el
index ae07f6237ce..5e5cd877e9b 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -4420,7 +4420,8 @@ run `deactivate-mark-hook'."
       ;; the region prior to the last command modifying the buffer.
       ;; Set the selection to that, or to the current region.
       (cond (saved-region-selection
-             (x-set-selection 'PRIMARY saved-region-selection)
+             (if (x-selection-owner-p 'PRIMARY)
+                 (x-set-selection 'PRIMARY saved-region-selection))
              (setq saved-region-selection nil))
             ;; If another program has acquired the selection, region
             ;; deactivation should not clobber it (Bug#11772).