Index: uspace/lib/cpp/include/internal/rbtree_iterators.hpp
===================================================================
--- uspace/lib/cpp/include/internal/rbtree_iterators.hpp	(revision b7cc0a90e62af91d1b6ef1d883a5f99d48289573)
+++ uspace/lib/cpp/include/internal/rbtree_iterators.hpp	(revision 349b0f749c344cd512e25815859fdcd7069ce079)
@@ -181,4 +181,8 @@
             using iterator_category = bidirectional_iterator_tag;
 
+            // For iterator_traits.
+            using reference = ConstReference;
+            using pointer   = ConstPointer;
+
             using node_type = Node;