diff --git a/include/armadillo_bits/BaseCube_bones.hpp b/include/armadillo_bits/BaseCube_bones.hpp
index 3c96e048..5e88a753 100644
--- a/include/armadillo_bits/BaseCube_bones.hpp
+++ b/include/armadillo_bits/BaseCube_bones.hpp
@@ -24,7 +24,7 @@
 template<typename elem_type, typename derived>
 struct BaseCube_eval_Cube
   {
-  arma_inline const derived& eval() const;
+  arma_inline arma_warn_unused const derived& eval() const;
   };
 
 
diff --git a/include/armadillo_bits/BaseCube_meat.hpp b/include/armadillo_bits/BaseCube_meat.hpp
index ac90d99d..af7b3c30 100644
--- a/include/armadillo_bits/BaseCube_meat.hpp
+++ b/include/armadillo_bits/BaseCube_meat.hpp
@@ -417,6 +417,7 @@ BaseCube<elem_type,derived>::has_nan() const
 
 template<typename elem_type, typename derived>
 arma_inline
+arma_warn_unused
 const derived&
 BaseCube_eval_Cube<elem_type, derived>::eval() const
   {