diff --git a/include/pybind11/numpy.h b/include/pybind11/numpy.h
index b35790bf1..eb4ee606e 100644
--- a/include/pybind11/numpy.h
+++ b/include/pybind11/numpy.h
@@ -147,7 +147,7 @@ NAMESPACE_BEGIN(detail)
 
 template <typename T> struct npy_format_descriptor<T, typename std::enable_if<std::is_integral<T>::value>::type> {
 private:
-    constexpr static const int values[] = {
+    constexpr static const int values[8] = {
         array::API::NPY_BYTE_, array::API::NPY_UBYTE_, array::API::NPY_SHORT_,    array::API::NPY_USHORT_,
         array::API::NPY_INT_,  array::API::NPY_UINT_,  array::API::NPY_LONGLONG_, array::API::NPY_ULONGLONG_ };
 public: