-void *_rb_find(const struct rb_type *, struct rbt_tree *, const void *);
-void *_rb_nfind(const struct rb_type *, struct rbt_tree *, const void *);
-void *_rb_root(const struct rb_type *, struct rbt_tree *);
-void *_rb_min(const struct rb_type *, struct rbt_tree *);
-void *_rb_max(const struct rb_type *, struct rbt_tree *);
+void *_rb_find(const struct rb_type *, const struct rbt_tree *, const void *);
+void *_rb_nfind(const struct rb_type *, const struct rbt_tree *, const void *);
+void *_rb_root(const struct rb_type *, const struct rbt_tree *);
+void *_rb_min(const struct rb_type *, const struct rbt_tree *);
+void *_rb_max(const struct rb_type *, const struct rbt_tree *);