message: Fix compilation with math constants with MSVC.
diff: @@ -16,6 +16,7 @@ limitations under the License.
  #ifndef TENSORFLOW_CORE_KERNELS_CWISE_OPS_H_
  #define TENSORFLOW_CORE_KERNELS_CWISE_OPS_H_
  +#define _USE_MATH_DEFINES
  #include <cmath>
  #include <functional>
  #include <type_traits>
  