// Use the implementation above for non function pointers
template <typename T, unsigned Select
= (unsigned)sizeof(::boost::type_traits::gcc8503::mini_funcptr_tester((T)0)) >
-struct cv_traits_imp : ::boost::type_traits::gcc8503::cv_traits_imp<T> { };
+struct cv_traits_imp : public ::boost::type_traits::gcc8503::cv_traits_imp<T> { };
// Functions are never cv-qualified
template <typename T> struct cv_traits_imp<T*,1>