Do not mark objects from deleted buffers, windows and frames.

* alloc.c (mark_buffer): Mark just the buffer if it is dead.
(mark_object): Likewise for windows and frames.

2 files changed, 48 insertions, 22 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 3d2e25f7828..a0c3f3537bb 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,11 @@
 2012-09-05  Dmitry Antipov  <dmantipov@yandex.ru>
 
+	Do not mark objects from deleted buffers, windows and frames.
+	* alloc.c (mark_buffer): Mark just the buffer if it is dead.
+	(mark_object): Likewise for windows and frames.
+
+2012-09-05  Dmitry Antipov  <dmantipov@yandex.ru>
+
 	* alloc.c (valid_lisp_object_p): Treat killed buffers,
 	buffer_defaults and buffer_local_symbols as valid objects.
 	Return special value to denote them.
diff --git a/src/alloc.c b/src/alloc.c
index 80ab2d2cb97..e90cca637df 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -5838,23 +5838,29 @@ mark_overlay (struct Lisp_Overlay *ptr)
 static void
 mark_buffer (struct buffer *buffer)
 {
-  /* This is handled much like other pseudovectors...  */
-  mark_vectorlike ((struct Lisp_Vector *) buffer);
+  if (NILP (BVAR (buffer, name)))
+    /* If the buffer is killed, mark just the buffer itself.  */
+    VECTOR_MARK (buffer);
+  else
+    {
+      /* This is handled much like other pseudovectors...  */
+      mark_vectorlike ((struct Lisp_Vector *) buffer);
 
-  /* ...but there are some buffer-specific things.  */
+      /* ...but there are some buffer-specific things.  */
 
-  MARK_INTERVAL_TREE (buffer_intervals (buffer));
+      MARK_INTERVAL_TREE (buffer_intervals (buffer));
 
-  /* For now, we just don't mark the undo_list.  It's done later in
-     a special way just before the sweep phase, and after stripping
-     some of its elements that are not needed any more.  */
+      /* For now, we just don't mark the undo_list.  It's done later in
+	 a special way just before the sweep phase, and after stripping
+	 some of its elements that are not needed any more.  */
 
-  mark_overlay (buffer->overlays_before);
-  mark_overlay (buffer->overlays_after);
+      mark_overlay (buffer->overlays_before);
+      mark_overlay (buffer->overlays_after);
 
-  /* If this is an indirect buffer, mark its base buffer.  */
-  if (buffer->base_buffer && !VECTOR_MARKED_P (buffer->base_buffer))
-    mark_buffer (buffer->base_buffer);
+      /* If this is an indirect buffer, mark its base buffer.  */
+      if (buffer->base_buffer && !VECTOR_MARKED_P (buffer->base_buffer))
+	mark_buffer (buffer->base_buffer);
+    }
 }
 
 /* Determine type of generic Lisp_Object and mark it accordingly.  */
@@ -5997,24 +6003,38 @@ mark_object (Lisp_Object arg)
 
 	  case PVEC_FRAME:
 	    {
-	      mark_vectorlike (ptr);
-	      mark_face_cache (((struct frame *) ptr)->face_cache);
+	      struct frame *f = (struct frame *) ptr;
+
+	      if (FRAME_LIVE_P (f))
+		{
+		  mark_vectorlike (ptr);
+		  mark_face_cache (f->face_cache);
+		}
+	      else
+		/* If the frame is deleted, mark just the frame itself.  */
+		VECTOR_MARK (ptr);
 	    }
 	    break;
 
 	  case PVEC_WINDOW:
 	    {
 	      struct window *w = (struct window *) ptr;
+	      bool leaf = NILP (w->hchild) && NILP (w->vchild);
 
-	      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 && NILP (w->buffer))
+		/* If the window is deleted, mark just the window itself.  */
+		VECTOR_MARK (ptr);
+	      else
 		{
-		  mark_glyph_matrix (w->current_matrix);
-		  mark_glyph_matrix (w->desired_matrix);
+		  mark_vectorlike (ptr);
+		  /* Mark glyphs for leaf windows.  Marking window
+		     matrices is sufficient because frame matrices
+		     use the same glyph memory.  */
+		  if (leaf && w->current_matrix)
+		    {
+		      mark_glyph_matrix (w->current_matrix);
+		      mark_glyph_matrix (w->desired_matrix);
+		    }
 		}
 	    }
 	    break;