diff --git a/include/eigenpy/deprecation-policy.hpp b/include/eigenpy/deprecation-policy.hpp
index e8660523febe7419f19861d9c8987ce4000e6053..42de0213cc56cc93d1add046591c4836577ecb2c 100644
--- a/include/eigenpy/deprecation-policy.hpp
+++ b/include/eigenpy/deprecation-policy.hpp
@@ -13,7 +13,7 @@ enum class DeprecationType { DEPRECATION, FUTURE };
 
 namespace detail {
 
-constexpr PyObject *deprecationTypeToPyObj(DeprecationType dep) {
+PyObject *deprecationTypeToPyObj(DeprecationType dep) {
   switch (dep) {
     case DeprecationType::DEPRECATION:
       return PyExc_DeprecationWarning;
diff --git a/include/eigenpy/numpy.hpp b/include/eigenpy/numpy.hpp
index f74349dd8b22b8886c4cd6306c342556927ca7c0..bf738b32f32cb0495d774daa8509799ccce1b3cf 100644
--- a/include/eigenpy/numpy.hpp
+++ b/include/eigenpy/numpy.hpp
@@ -150,15 +150,16 @@ struct NumpyEquivalentType<unsigned long> {
 
 template <typename Scalar>
 struct NumpyEquivalentType<
-    Scalar, std::enable_if_t<!std::is_same<int64_t, long long>::value &&
-                             std::is_same<Scalar, long long>::value> > {
+    Scalar,
+    typename std::enable_if<!std::is_same<int64_t, long long>::value &&
+                            std::is_same<Scalar, long long>::value>::type> {
   enum { type_code = NPY_LONGLONG };
 };
 template <typename Scalar>
 struct NumpyEquivalentType<
-    Scalar,
-    std::enable_if_t<!std::is_same<uint64_t, unsigned long long>::value &&
-                     std::is_same<Scalar, unsigned long long>::value> > {
+    Scalar, typename std::enable_if<
+                !std::is_same<uint64_t, unsigned long long>::value &&
+                std::is_same<Scalar, unsigned long long>::value>::type> {
   enum { type_code = NPY_ULONGLONG };
 };