diff --git a/libstdc++-v3/include/bits/stl_set.h b/libstdc++-v3/include/bits/stl_set.h
index c0eb4dbf65f..3d17626f330 100644
--- a/libstdc++-v3/include/bits/stl_set.h
+++ b/libstdc++-v3/include/bits/stl_set.h
@@ -875,7 +875,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
       template<typename _Kt>
 	auto
 	upper_bound(const _Kt& __x) const
-	-> decltype(iterator(_M_t._M_upper_bound_tr(__x)))
+	-> decltype(const_iterator(_M_t._M_upper_bound_tr(__x)))
 	{ return const_iterator(_M_t._M_upper_bound_tr(__x)); }
 #endif
       ///@}