* cp-tree.h (dfs_walk, dfs_walk_real, dfs_unmark, markedp,
	unmarkedp): Remove.
	(dfs_skip_bases, dfs_walk_all, dfs_walk_once): New.
	* class.c (struct find_final_overrider_data): Remove most_derived,
	vpath_list and vpath fields.  Add path field.
	(dfs_find_final_ocerrider_1): Add DEPTH parameter. Adjust.
	(dfs_find_final_overrider): Rename to ...
	(dfs_find_final_overrider_pre): ... here. Adjust.
	(dfs_find_final_overrider_post): Adjust.
	(dfs_find_final_overrider_q): Fold into
	dfs_find_final_overrider_pre.
	(find_final_overrider): Adjust dfs searching.
	(dfs_modify_vtables): Don't mark binfo here.
	(modify_all_vtables): Use dfs_walk_once.
	(build_vtt_inits): Likwise. Use dfs_walk_all.
	(dfs_build_secondary_vptr_vtt_inits): Don't mark binfo here.
	Return dfs_skip_bases as appropriate.
	(dfs_fixup_binfo_vtbls): Return dfs_skip_bases as appropriate.
	* init.c (dfs_initialized_vtbl_ptrs): Return dfs_skip_bases as
	appropriate. Don't mark binfo here.
	(initialize_vtbl_ptrs): Use dfs_walk_once.
	* search.c (struct vbase_info): Remove unused struct.
	(access_in_type): Use dfs_walk_once.
	(dfs_access_in_type): Don't mark binfo here.
	(dfs_accessible_queue_p, dfs_accessible_p) Remove.
	Fold into ...
	(accessible_r): ... here. New. Specialize dfs_walk_once.
	(accessible_p): Use accessible_r.
	(lookup_field_queue_p): Remove. Fold into ...
	(lookup_field_r): ... here. Adjust.
	(lookup_member): Use dfs_walk_all.
	(dfs_walk_real, dfs_walk): Replace with ...
	(dfs_walk_all, dfs_walk_once): ... these.
	(dfs_walk_once_r, dfs_unmark_r): Workers for dfs_walk_once.
	(dfs_unmark, unmarkedp, markedp): Remove.
	(dfs_get_pure_virtuals): Don't mark binfo here.
	(get_pure_virtuals): Use dfs_walk_once.
	(dfs_debug_unmarked_p): Remove. Fold into ...
	(dfs_debug_mark): ... here.
	(note_debug_info_needed): Use dfs_walk_all.

From-SVN: r88738