IDE highlights this code as wrong (code from /export/new_projects/boost_1_33_1/boost/detail/call_traits.hpp)

template <typename T, bool small_>
struct ct_imp2
{
   typedef const T& param_type;
};

template <typename T>
struct ct_imp2<T, true>
{
   typedef const T param_type;
};

template <typename T, bool isp, bool b1>
struct ct_imp
{
   typedef const T& param_type;
};

template <typename T, bool isp>
struct ct_imp<T, isp, true > {
    typedef typename ct_imp2<T, sizeof (T) <= sizeof (void*) >::param_type param_type;
};

int main() {
    return 0;
}