Align temporary array in TensorSelectOp packet evaluator.

unsupported/Eigen/CXX11/src/Tensor/TensorEvaluator.h

diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorEvaluator.h b/unsupported/Eigen/CXX11/src/Tensor/TensorEvaluator.h
index 6c81d53..bd9a7d8 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorEvaluator.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorEvaluator.h
@@ -789,7 +789,7 @@
 
   template <int LoadMode, bool UseTernary = TernaryPacketAccess, std::enable_if_t<!UseTernary, bool> = true>
   EIGEN_DEVICE_FUNC PacketReturnType packet(Index index) const {
-    std::remove_const_t<Scalar> arr[PacketSize];
+    EIGEN_ALIGN_TO_BOUNDARY(sizeof(PacketReturnType)) std::remove_const_t<Scalar> arr[PacketSize];
     EIGEN_UNROLL_LOOP
     for (Index i = 0; i < PacketSize; ++i) {
       arr[i] = m_condImpl.coeff(index + i) ? Scalar(-1) : Scalar(0);