Discard killed buffers from deleted window and frame objects.

[bpt/emacs.git] / src / alloc.c

diff --git a/src/alloc.c b/src/alloc.c
index 7bbc0ab..fb16b7d 100644 (file)
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -5865,6 +5865,32 @@ mark_buffer (struct buffer *buffer)
     mark_buffer (buffer->base_buffer);
 }
 
+/* Remove killed buffers or items whose car is a killed buffer
+   from LIST and return changed LIST.  Called during GC.  */
+
+static inline Lisp_Object
+discard_killed_buffers (Lisp_Object list)
+{
+  Lisp_Object tail, prev, tem;
+
+  for (tail = list, prev = Qnil; CONSP (tail); tail = XCDR (tail))
+    {
+      tem = XCAR (tail);
+      if (CONSP (tem))
+       tem = XCAR (tem);
+      if (BUFFERP (tem) && !BUFFER_LIVE_P (XBUFFER (tem)))
+       {
+         if (NILP (prev))
+           list = XCDR (tail);
+         else
+           XSETCDR (prev, XCDR (tail));
+       }
+      else
+       prev = tail;
+    }
+  return list;
+}
+
 /* Determine type of generic Lisp_Object and mark it accordingly.  */
 
 void
@@ -6001,20 +6027,41 @@ mark_object (Lisp_Object arg)
            break;
 
          case PVEC_FRAME:
-           mark_vectorlike (ptr);
-           mark_face_cache (((struct frame *) ptr)->face_cache);
+           {
+             struct frame *f = (struct frame *) ptr;
+
+             /* For live frames, killed buffers are filtered out by
+                store_frame_param.  For dead frames, we do it here in
+                attempt to help GC to reclaim killed buffers faster.  */
+             if (!FRAME_LIVE_P (f))
+               fset_buffer_list (f, discard_killed_buffers (f->buffer_list));
+
+             mark_vectorlike (ptr);
+             mark_face_cache (f->face_cache);
+           }
            break;
 
          case PVEC_WINDOW:
            {
              struct window *w = (struct window *) ptr;
+             bool leaf = NILP (w->hchild) && NILP (w->vchild);
+             
+             /* For live windows, Lisp code filters out killed buffers
+                from both buffer lists.  For dead windows, we do it here
+                in attempt to help GC to reclaim killed buffers faster.  */
+             if (leaf && NILP (w->buffer))
+               {
+                 wset_prev_buffers
+                   (w, discard_killed_buffers (w->prev_buffers));
+                 wset_next_buffers
+                   (w, discard_killed_buffers (w->next_buffers));
+               }
 
              mark_vectorlike (ptr);
              /* Mark glyphs for leaf windows.  Marking window
                 matrices is sufficient because frame matrices
                 use the same glyph memory.  */
-             if (NILP (w->hchild) && NILP (w->vchild)
-                 && w->current_matrix)
+             if (leaf && w->current_matrix)
                {
                  mark_glyph_matrix (w->current_matrix);
                  mark_glyph_matrix (w->desired_matrix);
@@ -6081,10 +6128,14 @@ mark_object (Lisp_Object arg)
          case SYMBOL_LOCALIZED:
            {
              struct Lisp_Buffer_Local_Value *blv = SYMBOL_BLV (ptr);
-             /* If the value is forwarded to a buffer or keyboard field,
-                these are marked when we see the corresponding object.
-                And if it's forwarded to a C variable, either it's not
-                a Lisp_Object var, or it's staticpro'd already.  */
+             Lisp_Object where = blv->where;
+             /* If the value is set up for a killed buffer or deleted
+                frame, restore it's global binding.  If the value is
+                forwarded to a C variable, either it's not a Lisp_Object
+                var, or it's staticpro'd already.  */
+             if ((BUFFERP (where) && !BUFFER_LIVE_P (XBUFFER (where)))
+                 || (FRAMEP (where) && !FRAME_LIVE_P (XFRAME (where))))
+               swap_in_global_binding (ptr);
              mark_object (blv->where);
              mark_object (blv->valcell);
              mark_object (blv->defcell);