diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorStorage.h b/unsupported/Eigen/CXX11/src/Tensor/TensorStorage.h
index 91aae091c..ae17c9610 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorStorage.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorStorage.h
@@ -66,7 +66,7 @@ template<typename T, DenseIndex NumIndices_, int Options_>
 class TensorStorage<T, NumIndices_, Dynamic, Options_, void>
   : public TensorStorage<T, NumIndices_, Dynamic, Options_, typename internal::gen_numeric_list_repeated<DenseIndex, NumIndices_, Dynamic>::type>
 {
-  typedef typename internal::compute_index_type<Options_ & Index32Bit>::type Index;
+  typedef typename internal::compute_index_type<static_cast<bool>(Options_ & Index32Bit)>::type Index;
   typedef DSizes<Index, NumIndices_> Dimensions;
   typedef TensorStorage<T, NumIndices_, Dynamic, Options_, typename internal::gen_numeric_list_repeated<DenseIndex, NumIndices_, Dynamic>::type> Base_;
 
@@ -85,7 +85,7 @@ template<typename T, DenseIndex NumIndices_, int Options_>
 class TensorStorage<T, NumIndices_, Dynamic, Options_, typename internal::gen_numeric_list_repeated<DenseIndex, NumIndices_, Dynamic>::type>
 {
   public:
-  typedef typename internal::compute_index_type<Options_&Index32Bit>::type Index;
+  typedef typename internal::compute_index_type<static_cast<bool>(Options_&Index32Bit)>::type Index;
   typedef DSizes<Index, NumIndices_> Dimensions;
 
     typedef TensorStorage<T, NumIndices_, Dynamic, Options_, typename internal::gen_numeric_list_repeated<DenseIndex, NumIndices_, Dynamic>::type> Self_;
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorTraits.h b/unsupported/Eigen/CXX11/src/Tensor/TensorTraits.h
index 424bb24eb..9a35b044d 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorTraits.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorTraits.h
@@ -60,7 +60,7 @@ struct traits<Tensor<Scalar_, NumIndices_, Options_> >
 {
   typedef Scalar_ Scalar;
   typedef Dense StorageKind;
-  typedef typename compute_index_type<Options_&Index32Bit>::type Index;
+  typedef typename compute_index_type<static_cast<bool>(Options_&Index32Bit)>::type Index;
   static const int NumDimensions = NumIndices_;
   static const int Layout = Options_ & RowMajor ? RowMajor : ColMajor;
   enum {
@@ -75,7 +75,7 @@ struct traits<TensorFixedSize<Scalar_, Dimensions, Options_> >
 {
   typedef Scalar_ Scalar;
   typedef Dense StorageKind;
-  typedef typename compute_index_type<Options_&Index32Bit>::type Index;
+  typedef typename compute_index_type<static_cast<bool>(Options_&Index32Bit)>::type Index;
   static const int NumDimensions = array_size<Dimensions>::value;
   static const int Layout = Options_ & RowMajor ? RowMajor : ColMajor;
   enum {