Discard killed buffers from deleted window and frame objects.

This reduces an amount of references to killed buffers and
helps GC to reclaim them faster.
* alloc.c (discard_killed_buffers): New function.
(mark_object): Use it for deleted windows and frames.
(mark_object): If symbol's value is set up for a killed buffer
or deleted frame, restore it's global binding.
* data.c (swap_in_global_binding): Add GC notice.
(swap_in_symval_forwarding): Use convenient set_blv_where.
* window.c (wset_next_buffers, wset_prev_buffers): Move ...
* window.h: ... to here.

1 files changed, 10 insertions, 1 deletions

diff --git a/src/window.h b/src/window.h
index a70bc55bac5..62ae43a999d 100644
--- a/src/window.h
+++ b/src/window.h
@@ -414,7 +414,16 @@ wset_window_end_vpos (struct window *w, Lisp_Object val)
 {
   w->window_end_vpos = val;
 }
-
+WINDOW_INLINE void
+wset_prev_buffers (struct window *w, Lisp_Object val)
+{
+  w->prev_buffers = val;
+}
+WINDOW_INLINE void
+wset_next_buffers (struct window *w, Lisp_Object val)
+{
+  w->next_buffers = val;
+}
 
 /* 1 if W is a minibuffer window.  */