Prevent core dump when connection is lost during frame creation.

* src/xfns.c (unwind_create_frame): Don't do anything if the frame is
  already dead.


git-archimport-id: lorentey@elte.hu--2004/emacs--multi-tty--0--patch-321

1 files changed, 6 insertions, 0 deletions

diff --git a/src/xfns.c b/src/xfns.c
index 66f0a2e94a4..6a9ec8a6b47 100644
--- a/src/xfns.c
+++ b/src/xfns.c
@@ -2952,6 +2952,12 @@ unwind_create_frame (frame)
 {
   struct frame *f = XFRAME (frame);
 
+  /* If frame is already dead, nothing to do.  This can happen if the
+     display is disconnected after the frame has become official, but
+     before x_create_frame removes the unwind protect.  */
+  if (!FRAME_LIVE_P (f))
+    return Qnil;
+
   /* If frame is ``official'', nothing to do.  */
   if (!CONSP (Vframe_list) || !EQ (XCAR (Vframe_list), frame))
     {