diff --git a/unsupported/Eigen/CXX11/Core b/unsupported/Eigen/CXX11/Core
index e3e2cb60c..946145f5a 100644
--- a/unsupported/Eigen/CXX11/Core
+++ b/unsupported/Eigen/CXX11/Core
@@ -33,6 +33,7 @@
 #include <vector>
 
 #include "src/Core/util/EmulateArray.h"
+#include "src/Core/util/MaxSizeVector.h"
 
 // Emulate the cxx11 functionality that we need if the compiler doesn't support it.
 // Visual studio 2015 doesn't advertise itself as cxx11 compliant, although it
diff --git a/unsupported/Eigen/CXX11/src/Core/util/MaxSizeVector.h b/unsupported/Eigen/CXX11/src/Core/util/MaxSizeVector.h
new file mode 100644
index 000000000..551124bae
--- /dev/null
+++ b/unsupported/Eigen/CXX11/src/Core/util/MaxSizeVector.h
@@ -0,0 +1,130 @@
+// This file is part of Eigen, a lightweight C++ template library
+// for linear algebra.
+//
+// Copyright (C) 2014 Benoit Steiner <benoit.steiner.goog@gmail.com>
+//
+// This Source Code Form is subject to the terms of the Mozilla
+// Public License v. 2.0. If a copy of the MPL was not distributed
+// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#ifndef EIGEN_FIXEDSIZEVECTOR_H
+#define EIGEN_FIXEDSIZEVECTOR_H
+
+namespace Eigen {
+
+/** \class MaxSizeVector
+  * \ingroup Core
+  *
+  * \brief The MaxSizeVector class.
+  *
+  * The %MaxSizeVector provides a subset of std::vector functionality.
+  *
+  * The goal is to provide basic std::vector operations when using
+  * std::vector is not an option (e.g. on GPU or when compiling using
+  * FMA/AVX, as this can cause either compilation failures or illegal
+  * instruction failures).
+  *
+  * Beware: The constructors are not API compatible with these of
+  * std::vector.
+  */
+template <typename T>
+class MaxSizeVector {
+ public:
+  // Construct a new MaxSizeVector, reserve n elements.
+  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
+  explicit MaxSizeVector(size_t n)
+      : reserve_(n), size_(0),
+        data_(static_cast<T*>(internal::aligned_malloc(n * sizeof(T)))) {
+    for (size_t i = 0; i < n; ++i) { new (&data_[i]) T; }
+  }
+
+  // Construct a new MaxSizeVector, reserve and resize to n.
+  // Copy the init value to all elements.
+  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
+  explicit MaxSizeVector(size_t n, const T& init)
+      : reserve_(n), size_(n),
+        data_(static_cast<T*>(internal::aligned_malloc(n * sizeof(T)))) {
+    for (size_t i = 0; i < n; ++i) { new (&data_[i]) T(init); }
+  }
+
+  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
+  ~MaxSizeVector() {
+    for (size_t i = 0; i < size_; ++i) {
+      data_[i].~T();
+    }
+    internal::aligned_free(data_);
+  }
+
+  // Append new elements (up to reserved size).
+  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
+  void push_back(const T& t) {
+    eigen_assert(size_ < reserve_);
+    data_[size_++] = t;
+  }
+
+  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
+  const T& operator[] (size_t i) const {
+    eigen_assert(i < size_);
+    return data_[i];
+  }
+
+  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
+  T& operator[] (size_t i) {
+    eigen_assert(i < size_);
+    return data_[i];
+  }
+
+  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
+  T& back() {
+    eigen_assert(size_ > 0);
+    return data_[size_ - 1];
+  }
+
+  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
+  const T& back() const {
+    eigen_assert(size_ > 0);
+    return data_[size_ - 1];
+  }
+
+  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
+  void pop_back() {
+    // NOTE: This does not destroy the value at the end the way
+    // std::vector's version of pop_back() does.  That happens when
+    // the Vector is destroyed.
+    eigen_assert(size_ > 0);
+    size_--;
+  }
+
+  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
+  size_t size() const { return size_; }
+
+  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
+  bool empty() const { return size_ == 0; }
+
+  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
+  T* data() { return data_; }
+
+  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
+  const T* data() const { return data_; }
+
+  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
+  T* begin() { return data_; }
+
+  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
+  T* end() { return data_ + size_; }
+
+  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
+  const T* begin() const { return data_; }
+
+  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
+  const T* end() const { return data_ + size_; }
+
+ private:
+  size_t reserve_;
+  size_t size_;
+  T* data_;
+};
+
+}  // namespace Eigen
+
+#endif  // EIGEN_FIXEDSIZEVECTOR_H
diff --git a/unsupported/Eigen/CXX11/src/Tensor/Tensor.h b/unsupported/Eigen/CXX11/src/Tensor/Tensor.h
index 17e485f0a..759dede3f 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/Tensor.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/Tensor.h
@@ -69,14 +69,11 @@ class Tensor : public TensorBase<Tensor<Scalar_, NumIndices_, Options_, IndexTyp
     typedef typename internal::traits<Self>::StorageKind StorageKind;
     typedef typename internal::traits<Self>::Index Index;
     typedef Scalar_ Scalar;
-    typedef typename internal::packet_traits<Scalar>::type Packet;
     typedef typename NumTraits<Scalar>::Real RealScalar;
     typedef typename Base::CoeffReturnType CoeffReturnType;
-    typedef typename Base::PacketReturnType PacketReturnType;
 
     enum {
       IsAligned = bool(EIGEN_MAX_ALIGN_BYTES>0) & !(Options_&DontAlign),
-      PacketAccess = (internal::packet_traits<Scalar>::size > 1),
       Layout = Options_ & RowMajor ? RowMajor : ColMajor,
       CoordAccess = true,
       RawAccess = true
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorAssign.h b/unsupported/Eigen/CXX11/src/Tensor/TensorAssign.h
index 10fac0cc5..199d2ce41 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorAssign.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorAssign.h
@@ -25,7 +25,6 @@ template<typename LhsXprType, typename RhsXprType>
 struct traits<TensorAssignOp<LhsXprType, RhsXprType> >
 {
   typedef typename LhsXprType::Scalar Scalar;
-  typedef typename internal::packet_traits<Scalar>::type Packet;
   typedef typename traits<LhsXprType>::StorageKind StorageKind;
   typedef typename promote_index_type<typename traits<LhsXprType>::Index,
                                       typename traits<RhsXprType>::Index>::type Index;
@@ -62,10 +61,8 @@ class TensorAssignOp : public TensorBase<TensorAssignOp<LhsXprType, RhsXprType>
 {
   public:
   typedef typename Eigen::internal::traits<TensorAssignOp>::Scalar Scalar;
-  typedef typename Eigen::internal::traits<TensorAssignOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename LhsXprType::CoeffReturnType CoeffReturnType;
-  typedef typename LhsXprType::PacketReturnType PacketReturnType;
   typedef typename Eigen::internal::nested<TensorAssignOp>::type Nested;
   typedef typename Eigen::internal::traits<TensorAssignOp>::StorageKind StorageKind;
   typedef typename Eigen::internal::traits<TensorAssignOp>::Index Index;
@@ -110,7 +107,7 @@ struct TensorEvaluator<const TensorAssignOp<LeftArgType, RightArgType>, Device>
   typedef typename XprType::Index Index;
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
   typedef typename TensorEvaluator<RightArgType, Device>::Dimensions Dimensions;
 
   EIGEN_DEVICE_FUNC const Dimensions& dimensions() const
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorBase.h b/unsupported/Eigen/CXX11/src/Tensor/TensorBase.h
index 66772a3ad..c854afd2f 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorBase.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorBase.h
@@ -31,7 +31,6 @@ class TensorBase<Derived, ReadOnlyAccessors>
     typedef typename DerivedTraits::Scalar Scalar;
     typedef typename DerivedTraits::Index Index;
     typedef typename internal::remove_const<Scalar>::type CoeffReturnType;
-    typedef typename internal::packet_traits<CoeffReturnType>::type PacketReturnType;
     static const int NumDimensions = DerivedTraits::NumDimensions;
 
     // Generic nullary operation support.
@@ -706,7 +705,6 @@ class TensorBase<Derived, WriteAccessors> : public TensorBase<Derived, ReadOnlyA
     typedef typename DerivedTraits::Scalar Scalar;
     typedef typename DerivedTraits::Index Index;
     typedef Scalar CoeffReturnType;
-    typedef typename internal::packet_traits<Scalar>::type PacketReturnType;
     static const int NumDimensions = DerivedTraits::NumDimensions;
 
     template <typename Scalar, int NumIndices, int Options, typename IndexType> friend class Tensor;
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorBroadcasting.h b/unsupported/Eigen/CXX11/src/Tensor/TensorBroadcasting.h
index efca7cd79..b6e6db12a 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorBroadcasting.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorBroadcasting.h
@@ -25,7 +25,6 @@ struct traits<TensorBroadcastingOp<Broadcast, XprType> > : public traits<XprType
 {
   typedef typename XprType::Scalar Scalar;
   typedef traits<XprType> XprTraits;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename XprTraits::StorageKind StorageKind;
   typedef typename XprTraits::Index Index;
   typedef typename XprType::Nested Nested;
@@ -70,10 +69,8 @@ class TensorBroadcastingOp : public TensorBase<TensorBroadcastingOp<Broadcast, X
 {
   public:
   typedef typename Eigen::internal::traits<TensorBroadcastingOp>::Scalar Scalar;
-  typedef typename Eigen::internal::traits<TensorBroadcastingOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
   typedef typename Eigen::internal::nested<TensorBroadcastingOp>::type Nested;
   typedef typename Eigen::internal::traits<TensorBroadcastingOp>::StorageKind StorageKind;
   typedef typename Eigen::internal::traits<TensorBroadcastingOp>::Index Index;
@@ -144,7 +141,7 @@ struct TensorEvaluator<const TensorBroadcastingOp<Broadcast, ArgType>, Device>
   }
 
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Dimensions& dimensions() const { return m_dimensions; }
 
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorChipping.h b/unsupported/Eigen/CXX11/src/Tensor/TensorChipping.h
index a209e885b..5023371ae 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorChipping.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorChipping.h
@@ -26,7 +26,6 @@ struct traits<TensorChippingOp<DimId, XprType> > : public traits<XprType>
 {
   typedef typename XprType::Scalar Scalar;
   typedef traits<XprType> XprTraits;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename XprTraits::StorageKind StorageKind;
   typedef typename XprTraits::Index Index;
   typedef typename XprType::Nested Nested;
@@ -80,10 +79,8 @@ class TensorChippingOp : public TensorBase<TensorChippingOp<DimId, XprType> >
 {
   public:
   typedef typename Eigen::internal::traits<TensorChippingOp>::Scalar Scalar;
-  typedef typename Eigen::internal::traits<TensorChippingOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
   typedef typename Eigen::internal::nested<TensorChippingOp>::type Nested;
   typedef typename Eigen::internal::traits<TensorChippingOp>::StorageKind StorageKind;
   typedef typename Eigen::internal::traits<TensorChippingOp>::Index Index;
@@ -184,7 +181,7 @@ struct TensorEvaluator<const TensorChippingOp<DimId, ArgType>, Device>
   }
 
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Dimensions& dimensions() const { return m_dimensions; }
 
@@ -313,7 +310,7 @@ struct TensorEvaluator<TensorChippingOp<DimId, ArgType>, Device>
     { }
 
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE CoeffReturnType& coeffRef(Index index)
   {
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorConcatenation.h b/unsupported/Eigen/CXX11/src/Tensor/TensorConcatenation.h
index f57d2bb7d..7738f18fb 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorConcatenation.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorConcatenation.h
@@ -26,7 +26,6 @@ struct traits<TensorConcatenationOp<Axis, LhsXprType, RhsXprType> >
   // Type promotion to handle the case where the types of the lhs and the rhs are different.
   typedef typename promote_storage_type<typename LhsXprType::Scalar,
                                         typename RhsXprType::Scalar>::ret Scalar;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename promote_storage_type<typename traits<LhsXprType>::StorageKind,
                                         typename traits<RhsXprType>::StorageKind>::ret StorageKind;
   typedef typename promote_index_type<typename traits<LhsXprType>::Index,
@@ -60,14 +59,11 @@ class TensorConcatenationOp : public TensorBase<TensorConcatenationOp<Axis, LhsX
 {
   public:
     typedef typename internal::traits<TensorConcatenationOp>::Scalar Scalar;
-    typedef typename internal::traits<TensorConcatenationOp>::Packet Packet;
     typedef typename internal::traits<TensorConcatenationOp>::StorageKind StorageKind;
     typedef typename internal::traits<TensorConcatenationOp>::Index Index;
     typedef typename internal::nested<TensorConcatenationOp>::type Nested;
     typedef typename internal::promote_storage_type<typename LhsXprType::CoeffReturnType,
                                                     typename RhsXprType::CoeffReturnType>::ret CoeffReturnType;
-    typedef typename internal::promote_storage_type<typename LhsXprType::PacketReturnType,
-                                                    typename RhsXprType::PacketReturnType>::ret PacketReturnType;
     typedef typename NumTraits<Scalar>::Real RealScalar;
 
     EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE TensorConcatenationOp(const LhsXprType& lhs, const RhsXprType& rhs, Axis axis)
@@ -120,7 +116,7 @@ struct TensorEvaluator<const TensorConcatenationOp<Axis, LeftArgType, RightArgTy
   typedef DSizes<Index, NumDims> Dimensions;
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
   enum {
     IsAligned = false,
     PacketAccess = TensorEvaluator<LeftArgType, Device>::PacketAccess & TensorEvaluator<RightArgType, Device>::PacketAccess,
@@ -300,7 +296,7 @@ template<typename Axis, typename LeftArgType, typename RightArgType, typename De
   typedef typename XprType::Index Index;
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE CoeffReturnType& coeffRef(Index index)
   {
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorContraction.h b/unsupported/Eigen/CXX11/src/Tensor/TensorContraction.h
index 1adb68894..18b20b2dc 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorContraction.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorContraction.h
@@ -27,7 +27,6 @@ struct traits<TensorContractionOp<Dimensions, LhsXprType, RhsXprType> >
   // Type promotion to handle the case where the types of the lhs and the rhs are different.
   typedef typename internal::promote_storage_type<typename LhsXprType::Scalar,
                                                   typename RhsXprType::Scalar>::ret Scalar;
-  typedef typename internal::packet_traits<Scalar>::type Packet;
   typedef typename promote_storage_type<typename traits<LhsXprType>::StorageKind,
                                         typename traits<RhsXprType>::StorageKind>::ret StorageKind;
   typedef typename promote_index_type<typename traits<LhsXprType>::Index,
@@ -76,11 +75,8 @@ class TensorContractionOp : public TensorBase<TensorContractionOp<Indices, LhsXp
 {
   public:
   typedef typename Eigen::internal::traits<TensorContractionOp>::Scalar Scalar;
-  typedef typename Eigen::internal::traits<TensorContractionOp>::Packet Packet;
   typedef typename internal::promote_storage_type<typename LhsXprType::CoeffReturnType,
                                                   typename RhsXprType::CoeffReturnType>::ret CoeffReturnType;
-  typedef typename internal::promote_storage_type<typename LhsXprType::PacketReturnType,
-                                                  typename RhsXprType::PacketReturnType>::ret PacketReturnType;
   typedef typename Eigen::internal::nested<TensorContractionOp>::type Nested;
   typedef typename Eigen::internal::traits<TensorContractionOp>::StorageKind StorageKind;
   typedef typename Eigen::internal::traits<TensorContractionOp>::Index Index;
@@ -118,14 +114,13 @@ struct TensorContractionEvaluatorBase
 
   typedef TensorContractionOp<Indices, LeftArgType, RightArgType> XprType;
   typedef typename internal::remove_const<typename XprType::Scalar>::type Scalar;
-  typedef typename XprType::Packet Packet;
   typedef typename XprType::Index Index;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   enum {
     IsAligned = true,
-    PacketAccess = (internal::packet_traits<Scalar>::size > 1),
+    PacketAccess = (internal::unpacket_traits<PacketReturnType>::size > 1),
     Layout = TensorEvaluator<LeftArgType, Device>::Layout,
     CoordAccess = false,  // to be implemented
     RawAccess = true
@@ -386,8 +381,8 @@ struct TensorContractionEvaluatorBase
     typedef typename internal::remove_const<typename EvalRightArgType::Scalar>::type RhsScalar;
     typedef TensorEvaluator<EvalLeftArgType, Device> LeftEvaluator;
     typedef TensorEvaluator<EvalRightArgType, Device> RightEvaluator;
-    const Index lhs_packet_size = internal::packet_traits<LhsScalar>::size;
-    const Index rhs_packet_size = internal::packet_traits<RhsScalar>::size;
+    const Index lhs_packet_size = internal::unpacket_traits<typename LeftEvaluator::PacketReturnType>::size;
+    const Index rhs_packet_size = internal::unpacket_traits<typename RightEvaluator::PacketReturnType>::size;
     const int lhs_alignment = LeftEvaluator::IsAligned ? Aligned : Unaligned;
     const int rhs_alignment = RightEvaluator::IsAligned ? Aligned : Unaligned;
     typedef internal::TensorContractionInputMapper<LhsScalar, Index, internal::Lhs,
@@ -434,7 +429,7 @@ struct TensorContractionEvaluatorBase
 
   template<int LoadMode>
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE PacketReturnType packet(Index index) const {
-    return internal::ploadt<Packet, LoadMode>(m_result + index);
+    return internal::ploadt<PacketReturnType, LoadMode>(m_result + index);
   }
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE Scalar* data() const { return m_result; }
@@ -478,10 +473,9 @@ struct TensorEvaluator<const TensorContractionOp<Indices, LeftArgType, RightArgT
 
   typedef TensorContractionOp<Indices, LeftArgType, RightArgType> XprType;
   typedef typename internal::remove_const<typename XprType::Scalar>::type Scalar;
-  typedef typename XprType::Packet Packet;
   typedef typename XprType::Index Index;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   enum {
     Layout = TensorEvaluator<LeftArgType, Device>::Layout,
@@ -550,8 +544,8 @@ struct TensorEvaluator<const TensorContractionOp<Indices, LeftArgType, RightArgT
     typedef TensorEvaluator<EvalLeftArgType, Device> LeftEvaluator;
     typedef TensorEvaluator<EvalRightArgType, Device> RightEvaluator;
 
-    const Index lhs_packet_size = internal::packet_traits<LhsScalar>::size;
-    const Index rhs_packet_size = internal::packet_traits<RhsScalar>::size;
+    const Index lhs_packet_size = internal::unpacket_traits<typename LeftEvaluator::PacketReturnType>::size;
+    const Index rhs_packet_size = internal::unpacket_traits<typename RightEvaluator::PacketReturnType>::size;
 
     typedef internal::TensorContractionInputMapper<LhsScalar, Index, internal::Lhs,
                                                    LeftEvaluator, left_nocontract_t,
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorContractionCuda.h b/unsupported/Eigen/CXX11/src/Tensor/TensorContractionCuda.h
index f5b539c7e..a4a06ab5f 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorContractionCuda.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorContractionCuda.h
@@ -1213,10 +1213,9 @@ struct TensorEvaluator<const TensorContractionOp<Indices, LeftArgType, RightArgT
 
   typedef TensorContractionOp<Indices, LeftArgType, RightArgType> XprType;
   typedef typename internal::remove_const<typename XprType::Scalar>::type Scalar;
-  typedef typename XprType::Packet Packet;
   typedef typename XprType::Index Index;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, GpuDevice>::type PacketReturnType;
 
   enum {
     Layout = TensorEvaluator<LeftArgType, Device>::Layout,
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorContractionMapper.h b/unsupported/Eigen/CXX11/src/Tensor/TensorContractionMapper.h
index 392aa6d37..c38747532 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorContractionMapper.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorContractionMapper.h
@@ -230,8 +230,8 @@ class BaseTensorContractionMapper : public SimpleTensorContractionMapper<Scalar,
                               const contract_t& k_strides) :
   ParentMapper(tensor, nocontract_strides, ij_strides, contract_strides, k_strides) { }
 
-  typedef typename packet_traits<Scalar>::type Packet;
-  typedef typename packet_traits<Scalar>::half HalfPacket;
+  typedef typename Tensor::PacketReturnType Packet;
+  typedef typename unpacket_traits<Packet>::half HalfPacket;
 
   template <int AlignmentType = Alignment>
   EIGEN_DEVICE_FUNC
@@ -313,12 +313,12 @@ class BaseTensorContractionMapper<Scalar, Index, side, Tensor, nocontract_t, con
                               const contract_t& k_strides) :
   ParentMapper(tensor, nocontract_strides, ij_strides, contract_strides, k_strides) { }
 
-  typedef typename packet_traits<Scalar>::type Packet;
+  typedef typename Tensor::PacketReturnType Packet;
   template <int> EIGEN_DEVICE_FUNC
   EIGEN_STRONG_INLINE Packet loadPacket(Index i, Index j) const {
     EIGEN_ALIGN_MAX Scalar data[1];
     data[0] = this->m_tensor.coeff(this->computeIndex(i, j));
-    return pload<typename packet_traits<Scalar>::type>(data);
+    return pload<typename Tensor::PacketReturntype>(data);
   }
   template <int> EIGEN_DEVICE_FUNC
   EIGEN_STRONG_INLINE Packet loadHalfPacket(Index i, Index j) const {
@@ -334,8 +334,8 @@ template<typename Scalar, typename Index, int side,
          bool inner_dim_contiguous, bool inner_dim_reordered, int Alignment>
 class TensorContractionSubMapper {
  public:
-  typedef typename packet_traits<Scalar>::type Packet;
-  typedef typename packet_traits<Scalar>::half HalfPacket;
+  typedef typename Tensor::PacketReturnType Packet;
+  typedef typename unpacket_traits<Packet>::half HalfPacket;
 
   typedef BaseTensorContractionMapper<Scalar, Index, side, Tensor, nocontract_t, contract_t, packet_size, inner_dim_contiguous, inner_dim_reordered, Alignment> ParentMapper;
   typedef TensorContractionSubMapper<Scalar, Index, side, Tensor, nocontract_t, contract_t, packet_size, inner_dim_contiguous, inner_dim_reordered, Alignment> Self;
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorContractionThreadPool.h b/unsupported/Eigen/CXX11/src/Tensor/TensorContractionThreadPool.h
index 51a3b9490..9044454fd 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorContractionThreadPool.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorContractionThreadPool.h
@@ -28,7 +28,7 @@ struct packLhsArg {
 
 template<typename LhsScalar, typename RhsScalar, typename RhsMapper, typename OutputMapper, typename Index>
 struct packRhsAndKernelArg {
-  const std::vector<LhsScalar*>* blockAs;
+  const MaxSizeVector<LhsScalar*>* blockAs;
   RhsScalar* blockB;
   const RhsMapper& rhs;
   OutputMapper& output;
@@ -46,8 +46,8 @@ struct packRhsAndKernelArg {
   const Index n_block_idx;
   const Index m_blocks;
   const Index n_blocks;
-  std::vector<Notification*>* kernel_notifications;
-  const std::vector<Notification*>* lhs_notifications;
+  MaxSizeVector<Notification*>* kernel_notifications;
+  const MaxSizeVector<Notification*>* lhs_notifications;
   const bool need_to_pack;
 };
 
@@ -65,10 +65,9 @@ struct TensorEvaluator<const TensorContractionOp<Indices, LeftArgType, RightArgT
 
   typedef TensorContractionOp<Indices, LeftArgType, RightArgType> XprType;
   typedef typename internal::remove_const<typename XprType::Scalar>::type Scalar;
-  typedef typename XprType::Packet Packet;
   typedef typename XprType::Index Index;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   enum {
     Layout = TensorEvaluator<LeftArgType, Device>::Layout,
@@ -136,8 +135,8 @@ struct TensorEvaluator<const TensorContractionOp<Indices, LeftArgType, RightArgT
     this->m_device.memset(buffer, 0, m * n * sizeof(Scalar));
 
 
-    const int lhs_packet_size = internal::packet_traits<LhsScalar>::size;
-    const int rhs_packet_size = internal::packet_traits<RhsScalar>::size;
+    const int lhs_packet_size = internal::unpacket_traits<typename LeftEvaluator::PacketReturnType>::size;
+    const int rhs_packet_size = internal::unpacket_traits<typename RightEvaluator::PacketReturnType>::size;
 
     typedef internal::TensorContractionInputMapper<LhsScalar, Index, internal::Lhs,
                                                    LeftEvaluator, left_nocontract_t,
@@ -203,8 +202,7 @@ struct TensorEvaluator<const TensorContractionOp<Indices, LeftArgType, RightArgT
     //       the alignment requirements with the assumption that
     //       (Traits::mr * sizeof(ResScalar)) % 16 == 0
     const Index numBlockAs = numext::mini(num_threads, m_blocks);
-    std::vector<LhsScalar *> blockAs;
-    blockAs.reserve(num_threads);
+    MaxSizeVector<LhsScalar *> blockAs(num_threads);
     for (int i = 0; i < num_threads; i++) {
       blockAs.push_back(static_cast<LhsScalar *>(this->m_device.allocate(sizeA * sizeof(LhsScalar))));
     }
@@ -213,18 +211,17 @@ struct TensorEvaluator<const TensorContractionOp<Indices, LeftArgType, RightArgT
     // TODO: is this too much memory to allocate? This simplifies coding a lot, but is wasteful.
     //       Other options: (1) reuse memory when a thread finishes. con: tricky
     //                      (2) allocate block B memory in each thread. con: overhead
-    std::vector<RhsScalar *> blockBs;
-    blockBs.reserve(n_blocks);
+    MaxSizeVector<RhsScalar *> blockBs(n_blocks);
     for (int i = 0; i < n_blocks; i++) {
       blockBs.push_back(static_cast<RhsScalar *>(this->m_device.allocate(sizeB * sizeof(RhsScalar))));
     }
 
     // lhs_notifications starts with all null Notifications
-    std::vector<Notification*> lhs_notifications(num_threads, nullptr);
+    MaxSizeVector<Notification*> lhs_notifications(num_threads, nullptr);
 
     // this should really be numBlockAs * n_blocks;
     const Index num_kernel_notifications = num_threads * n_blocks;
-    std::vector<Notification*> kernel_notifications(num_kernel_notifications,
+    MaxSizeVector<Notification*> kernel_notifications(num_kernel_notifications,
                                                     nullptr);
 
     for (Index k_block_idx = 0; k_block_idx < k_blocks; k_block_idx++) {
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorConversion.h b/unsupported/Eigen/CXX11/src/Tensor/TensorConversion.h
index 4e87813a9..f2dee3ee8 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorConversion.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorConversion.h
@@ -25,7 +25,6 @@ struct traits<TensorConversionOp<TargetType, XprType> >
 {
   // Type promotion to handle the case where the types of the lhs and the rhs are different.
   typedef TargetType Scalar;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename traits<XprType>::StorageKind StorageKind;
   typedef typename traits<XprType>::Index Index;
   typedef typename XprType::Nested Nested;
@@ -146,12 +145,10 @@ class TensorConversionOp : public TensorBase<TensorConversionOp<TargetType, XprT
 {
   public:
     typedef typename internal::traits<TensorConversionOp>::Scalar Scalar;
-    typedef typename internal::traits<TensorConversionOp>::Packet Packet;
     typedef typename internal::traits<TensorConversionOp>::StorageKind StorageKind;
     typedef typename internal::traits<TensorConversionOp>::Index Index;
     typedef typename internal::nested<TensorConversionOp>::type Nested;
     typedef Scalar CoeffReturnType;
-    typedef Packet PacketReturnType;
     typedef typename NumTraits<Scalar>::Real RealScalar;
 
     EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE TensorConversionOp(const XprType& xpr)
@@ -190,8 +187,8 @@ struct TensorEvaluator<const TensorConversionOp<TargetType, ArgType>, Device>
   typedef TargetType Scalar;
   typedef TargetType CoeffReturnType;
   typedef typename internal::remove_all<typename internal::traits<ArgType>::Scalar>::type SrcType;
-  typedef typename internal::traits<XprType>::Packet PacketReturnType;
-  typedef typename internal::packet_traits<SrcType>::type PacketSourceType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
+  typedef typename PacketType<SrcType, Device>::type PacketSourceType;
 
   enum {
     IsAligned = false,
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorConvolution.h b/unsupported/Eigen/CXX11/src/Tensor/TensorConvolution.h
index 67c797802..4fe1fb943 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorConvolution.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorConvolution.h
@@ -221,7 +221,6 @@ struct traits<TensorConvolutionOp<Dimensions, InputXprType, KernelXprType> >
   // Type promotion to handle the case where the types of the lhs and the rhs are different.
   typedef typename promote_storage_type<typename InputXprType::Scalar,
                                         typename KernelXprType::Scalar>::ret Scalar;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename promote_storage_type<typename traits<InputXprType>::StorageKind,
                                         typename traits<KernelXprType>::StorageKind>::ret StorageKind;
   typedef typename promote_index_type<typename traits<InputXprType>::Index,
@@ -259,12 +258,9 @@ class TensorConvolutionOp : public TensorBase<TensorConvolutionOp<Indices, Input
 {
   public:
   typedef typename Eigen::internal::traits<TensorConvolutionOp>::Scalar Scalar;
-  typedef typename Eigen::internal::traits<TensorConvolutionOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename internal::promote_storage_type<typename InputXprType::CoeffReturnType,
                                                   typename KernelXprType::CoeffReturnType>::ret CoeffReturnType;
-  typedef typename internal::promote_storage_type<typename InputXprType::PacketReturnType,
-                                                  typename KernelXprType::PacketReturnType>::ret PacketReturnType;
   typedef typename Eigen::internal::nested<TensorConvolutionOp>::type Nested;
   typedef typename Eigen::internal::traits<TensorConvolutionOp>::StorageKind StorageKind;
   typedef typename Eigen::internal::traits<TensorConvolutionOp>::Index Index;
@@ -373,7 +369,7 @@ struct TensorEvaluator<const TensorConvolutionOp<Indices, InputArgType, KernelAr
 
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Dimensions& dimensions() const { return m_dimensions; }
 
@@ -775,7 +771,7 @@ struct TensorEvaluator<const TensorConvolutionOp<Indices, InputArgType, KernelAr
   }
 
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, GpuDevice>::type PacketReturnType;
   typedef typename InputArgType::Scalar Scalar;
 
   EIGEN_DEVICE_FUNC const Dimensions& dimensions() const { return m_dimensions; }
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorCustomOp.h b/unsupported/Eigen/CXX11/src/Tensor/TensorCustomOp.h
index 0f8a98caf..b58e513b4 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorCustomOp.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorCustomOp.h
@@ -24,7 +24,6 @@ template<typename CustomUnaryFunc, typename XprType>
 struct traits<TensorCustomUnaryOp<CustomUnaryFunc, XprType> >
 {
   typedef typename XprType::Scalar Scalar;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename XprType::StorageKind StorageKind;
   typedef typename XprType::Index Index;
   typedef typename XprType::Nested Nested;
@@ -54,10 +53,8 @@ class TensorCustomUnaryOp : public TensorBase<TensorCustomUnaryOp<CustomUnaryFun
 {
   public:
   typedef typename internal::traits<TensorCustomUnaryOp>::Scalar Scalar;
-  typedef typename internal::traits<TensorCustomUnaryOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
   typedef typename internal::nested<TensorCustomUnaryOp>::type Nested;
   typedef typename internal::traits<TensorCustomUnaryOp>::StorageKind StorageKind;
   typedef typename internal::traits<TensorCustomUnaryOp>::Index Index;
@@ -105,7 +102,7 @@ struct TensorEvaluator<const TensorCustomUnaryOp<CustomUnaryFunc, XprType>, Devi
   }
 
   typedef typename internal::remove_const<typename XprType::CoeffReturnType>::type CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Dimensions& dimensions() const { return m_dimensions; }
 
@@ -167,11 +164,8 @@ struct traits<TensorCustomBinaryOp<CustomBinaryFunc, LhsXprType, RhsXprType> >
 {
   typedef typename internal::promote_storage_type<typename LhsXprType::Scalar,
                                                   typename RhsXprType::Scalar>::ret Scalar;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename internal::promote_storage_type<typename LhsXprType::CoeffReturnType,
                                                   typename RhsXprType::CoeffReturnType>::ret CoeffReturnType;
-  typedef typename internal::promote_storage_type<typename LhsXprType::PacketReturnType,
-                                                  typename RhsXprType::PacketReturnType>::ret PacketReturnType;
   typedef typename promote_storage_type<typename traits<LhsXprType>::StorageKind,
                                         typename traits<RhsXprType>::StorageKind>::ret StorageKind;
   typedef typename promote_index_type<typename traits<LhsXprType>::Index,
@@ -205,10 +199,8 @@ class TensorCustomBinaryOp : public TensorBase<TensorCustomBinaryOp<CustomBinary
 {
   public:
   typedef typename internal::traits<TensorCustomBinaryOp>::Scalar Scalar;
-  typedef typename internal::traits<TensorCustomBinaryOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename internal::traits<TensorCustomBinaryOp>::CoeffReturnType CoeffReturnType;
-  typedef typename internal::traits<TensorCustomBinaryOp>::PacketReturnType PacketReturnType;
   typedef typename internal::nested<TensorCustomBinaryOp>::type Nested;
   typedef typename internal::traits<TensorCustomBinaryOp>::StorageKind StorageKind;
   typedef typename internal::traits<TensorCustomBinaryOp>::Index Index;
@@ -261,7 +253,7 @@ struct TensorEvaluator<const TensorCustomBinaryOp<CustomBinaryFunc, LhsXprType,
   }
 
   typedef typename internal::remove_const<typename XprType::CoeffReturnType>::type CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Dimensions& dimensions() const { return m_dimensions; }
 
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorEvalTo.h b/unsupported/Eigen/CXX11/src/Tensor/TensorEvalTo.h
index bd83d5de8..5d73d62d2 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorEvalTo.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorEvalTo.h
@@ -26,7 +26,6 @@ struct traits<TensorEvalToOp<XprType> >
   // Type promotion to handle the case where the types of the lhs and the rhs are different.
   typedef typename XprType::Scalar Scalar;
   typedef traits<XprType> XprTraits;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename XprTraits::StorageKind StorageKind;
   typedef typename XprTraits::Index Index;
   typedef typename XprType::Nested Nested;
@@ -61,10 +60,8 @@ class TensorEvalToOp : public TensorBase<TensorEvalToOp<XprType> >
 {
   public:
   typedef typename Eigen::internal::traits<TensorEvalToOp>::Scalar Scalar;
-  typedef typename Eigen::internal::traits<TensorEvalToOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename internal::remove_const<typename XprType::CoeffReturnType>::type CoeffReturnType;
-  typedef typename internal::remove_const<typename XprType::PacketReturnType>::type PacketReturnType;
   typedef typename Eigen::internal::nested<TensorEvalToOp>::type Nested;
   typedef typename Eigen::internal::traits<TensorEvalToOp>::StorageKind StorageKind;
   typedef typename Eigen::internal::traits<TensorEvalToOp>::Index Index;
@@ -90,7 +87,6 @@ struct TensorEvaluator<const TensorEvalToOp<ArgType>, Device>
 {
   typedef TensorEvalToOp<ArgType> XprType;
   typedef typename ArgType::Scalar Scalar;
-  typedef typename ArgType::Packet Packet;
   typedef typename TensorEvaluator<ArgType, Device>::Dimensions Dimensions;
 
   enum {
@@ -110,7 +106,7 @@ struct TensorEvaluator<const TensorEvalToOp<ArgType>, Device>
 
   typedef typename XprType::Index Index;
   typedef typename internal::remove_const<typename XprType::CoeffReturnType>::type CoeffReturnType;
-  typedef typename internal::remove_const<typename XprType::PacketReturnType>::type PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC const Dimensions& dimensions() const { return m_impl.dimensions(); }
 
@@ -138,7 +134,7 @@ struct TensorEvaluator<const TensorEvalToOp<ArgType>, Device>
   template<int LoadMode>
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE PacketReturnType packet(Index index) const
   {
-    return internal::ploadt<Packet, LoadMode>(m_buffer + index);
+    return internal::ploadt<PacketReturnType, LoadMode>(m_buffer + index);
   }
 
   EIGEN_DEVICE_FUNC CoeffReturnType* data() const { return m_buffer; }
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorEvaluator.h b/unsupported/Eigen/CXX11/src/Tensor/TensorEvaluator.h
index f726585b1..947a8ed88 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorEvaluator.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorEvaluator.h
@@ -29,9 +29,8 @@ struct TensorEvaluator
 {
   typedef typename Derived::Index Index;
   typedef typename Derived::Scalar Scalar;
-  typedef typename Derived::Packet Packet;
   typedef typename Derived::Scalar CoeffReturnType;
-  typedef typename Derived::Packet PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
   typedef typename Derived::Dimensions Dimensions;
 
   // NumDimensions is -1 for variable dim tensors
@@ -40,7 +39,7 @@ struct TensorEvaluator
 
   enum {
     IsAligned = Derived::IsAligned,
-    PacketAccess = Derived::PacketAccess,
+    PacketAccess = (internal::unpacket_traits<PacketReturnType>::size > 1),
     Layout = Derived::Layout,
     CoordAccess = NumCoords > 0,
     RawAccess = true
@@ -75,13 +74,13 @@ struct TensorEvaluator
   template<int LoadMode> EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
   PacketReturnType packet(Index index) const
   {
-    return internal::ploadt<Packet, LoadMode>(m_data + index);
+    return internal::ploadt<PacketReturnType, LoadMode>(m_data + index);
   }
 
   template <int StoreMode> EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
-  void writePacket(Index index, const Packet& x)
+  void writePacket(Index index, const PacketReturnType& x)
   {
-    return internal::pstoret<Scalar, Packet, StoreMode>(m_data + index, x);
+    return internal::pstoret<Scalar, PacketReturnType, StoreMode>(m_data + index, x);
   }
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE CoeffReturnType coeff(const array<DenseIndex, NumCoords>& coords) const {
@@ -135,9 +134,8 @@ struct TensorEvaluator<const Derived, Device>
 {
   typedef typename Derived::Index Index;
   typedef typename Derived::Scalar Scalar;
-  typedef typename Derived::Packet Packet;
   typedef typename Derived::Scalar CoeffReturnType;
-  typedef typename Derived::Packet PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
   typedef typename Derived::Dimensions Dimensions;
 
   // NumDimensions is -1 for variable dim tensors
@@ -146,7 +144,7 @@ struct TensorEvaluator<const Derived, Device>
 
   enum {
     IsAligned = Derived::IsAligned,
-    PacketAccess = Derived::PacketAccess,
+    PacketAccess = (internal::unpacket_traits<PacketReturnType>::size > 1),
     Layout = Derived::Layout,
     CoordAccess = NumCoords > 0,
     RawAccess = true
@@ -176,7 +174,7 @@ struct TensorEvaluator<const Derived, Device>
   template<int LoadMode> EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
   PacketReturnType packet(Index index) const
   {
-    return internal::ploadt_ro<Packet, LoadMode>(m_data + index);
+    return internal::ploadt_ro<PacketReturnType, LoadMode>(m_data + index);
   }
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE CoeffReturnType coeff(const array<DenseIndex, NumCoords>& coords) const {
@@ -220,7 +218,7 @@ struct TensorEvaluator<const TensorCwiseNullaryOp<NullaryOp, ArgType>, Device>
   typedef typename XprType::Index Index;
   typedef typename XprType::Scalar Scalar;
   typedef typename internal::traits<XprType>::Scalar CoeffReturnType;
-  typedef typename internal::traits<XprType>::Packet PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
   typedef typename TensorEvaluator<ArgType, Device>::Dimensions Dimensions;
 
   EIGEN_DEVICE_FUNC const Dimensions& dimensions() const { return m_argImpl.dimensions(); }
@@ -236,7 +234,7 @@ struct TensorEvaluator<const TensorCwiseNullaryOp<NullaryOp, ArgType>, Device>
   template<int LoadMode>
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE PacketReturnType packet(Index index) const
   {
-    return m_functor.template packetOp<Index,PacketReturnType>(index);
+    return m_functor.template packetOp<Index, PacketReturnType>(index);
   }
 
   EIGEN_DEVICE_FUNC CoeffReturnType* data() const { return NULL; }
@@ -271,7 +269,7 @@ struct TensorEvaluator<const TensorCwiseUnaryOp<UnaryOp, ArgType>, Device>
   typedef typename XprType::Index Index;
   typedef typename XprType::Scalar Scalar;
   typedef typename internal::traits<XprType>::Scalar CoeffReturnType;
-  typedef typename internal::traits<XprType>::Packet PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
   typedef typename TensorEvaluator<ArgType, Device>::Dimensions Dimensions;
 
   EIGEN_DEVICE_FUNC const Dimensions& dimensions() const { return m_argImpl.dimensions(); }
@@ -331,7 +329,7 @@ struct TensorEvaluator<const TensorCwiseBinaryOp<BinaryOp, LeftArgType, RightArg
   typedef typename XprType::Index Index;
   typedef typename XprType::Scalar Scalar;
   typedef typename internal::traits<XprType>::Scalar CoeffReturnType;
-  typedef typename internal::traits<XprType>::Packet PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
   typedef typename TensorEvaluator<LeftArgType, Device>::Dimensions Dimensions;
 
   EIGEN_DEVICE_FUNC const Dimensions& dimensions() const
@@ -399,7 +397,7 @@ struct TensorEvaluator<const TensorSelectOp<IfArgType, ThenArgType, ElseArgType>
 
   typedef typename XprType::Index Index;
   typedef typename internal::traits<XprType>::Scalar CoeffReturnType;
-  typedef typename internal::traits<XprType>::Packet PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
   typedef typename TensorEvaluator<IfArgType, Device>::Dimensions Dimensions;
 
   EIGEN_DEVICE_FUNC const Dimensions& dimensions() const
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorExecutor.h b/unsupported/Eigen/CXX11/src/Tensor/TensorExecutor.h
index fd9919829..54da77bcf 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorExecutor.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorExecutor.h
@@ -127,8 +127,7 @@ class TensorExecutor<Expression, ThreadPoolDevice, Vectorizable>
       const Index blocksize = numext::maxi<Index>(PacketSize, (blocksz - (blocksz % PacketSize)));
       const Index numblocks = size / blocksize;
 
-      std::vector<Notification*> results;
-      results.reserve(numblocks);
+      MaxSizeVector<Notification*> results(numblocks);
       for (int i = 0; i < numblocks; ++i) {
         results.push_back(device.enqueue(&EvalRange<Evaluator, Index, Vectorizable>::run, evaluator, i*blocksize, (i+1)*blocksize));
       }
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorExpr.h b/unsupported/Eigen/CXX11/src/Tensor/TensorExpr.h
index 194c68929..49d849e23 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorExpr.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorExpr.h
@@ -32,7 +32,6 @@ template<typename NullaryOp, typename XprType>
 struct traits<TensorCwiseNullaryOp<NullaryOp, XprType> >
     : traits<XprType>
 {
-  typedef typename XprType::Packet Packet;
   typedef traits<XprType> XprTraits;
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::Nested XprTypeNested;
@@ -54,10 +53,8 @@ class TensorCwiseNullaryOp : public TensorBase<TensorCwiseNullaryOp<NullaryOp, X
 {
   public:
     typedef typename Eigen::internal::traits<TensorCwiseNullaryOp>::Scalar Scalar;
-    typedef typename Eigen::internal::traits<TensorCwiseNullaryOp>::Packet Packet;
     typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
     typedef typename XprType::CoeffReturnType CoeffReturnType;
-    typedef typename XprType::PacketReturnType PacketReturnType;
     typedef TensorCwiseNullaryOp<NullaryOp, XprType> Nested;
     typedef typename Eigen::internal::traits<TensorCwiseNullaryOp>::StorageKind StorageKind;
     typedef typename Eigen::internal::traits<TensorCwiseNullaryOp>::Index Index;
@@ -88,7 +85,6 @@ struct traits<TensorCwiseUnaryOp<UnaryOp, XprType> >
   // current Scalar/Packet to see if the intent is Input or Output.
   typedef typename result_of<UnaryOp(typename XprType::Scalar)>::type Scalar;
   typedef traits<XprType> XprTraits;
-  typedef typename internal::packet_traits<Scalar>::type Packet;
   typedef typename XprType::Nested XprTypeNested;
   typedef typename remove_reference<XprTypeNested>::type _XprTypeNested;
   static const int NumDimensions = XprTraits::NumDimensions;
@@ -118,10 +114,8 @@ class TensorCwiseUnaryOp : public TensorBase<TensorCwiseUnaryOp<UnaryOp, XprType
     // TODO(phli): Add InputScalar, InputPacket.  Check references to
     // current Scalar/Packet to see if the intent is Input or Output.
     typedef typename Eigen::internal::traits<TensorCwiseUnaryOp>::Scalar Scalar;
-    typedef typename Eigen::internal::traits<TensorCwiseUnaryOp>::Packet Packet;
     typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
     typedef Scalar CoeffReturnType;
-    typedef typename internal::packet_traits<CoeffReturnType>::type PacketReturnType;
     typedef typename Eigen::internal::nested<TensorCwiseUnaryOp>::type Nested;
     typedef typename Eigen::internal::traits<TensorCwiseUnaryOp>::StorageKind StorageKind;
     typedef typename Eigen::internal::traits<TensorCwiseUnaryOp>::Index Index;
@@ -155,7 +149,6 @@ struct traits<TensorCwiseBinaryOp<BinaryOp, LhsXprType, RhsXprType> >
       BinaryOp(typename LhsXprType::Scalar,
                typename RhsXprType::Scalar)>::type Scalar;
   typedef traits<LhsXprType> XprTraits;
-  typedef typename internal::packet_traits<Scalar>::type Packet;
   typedef typename promote_storage_type<
       typename traits<LhsXprType>::StorageKind,
       typename traits<RhsXprType>::StorageKind>::ret StorageKind;
@@ -197,10 +190,8 @@ class TensorCwiseBinaryOp : public TensorBase<TensorCwiseBinaryOp<BinaryOp, LhsX
     // TODO(phli): Add Lhs/RhsScalar, Lhs/RhsPacket.  Check references to
     // current Scalar/Packet to see if the intent is Inputs or Output.
     typedef typename Eigen::internal::traits<TensorCwiseBinaryOp>::Scalar Scalar;
-    typedef typename Eigen::internal::traits<TensorCwiseBinaryOp>::Packet Packet;
     typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
     typedef Scalar CoeffReturnType;
-    typedef typename internal::packet_traits<CoeffReturnType>::type PacketReturnType;
     typedef typename Eigen::internal::nested<TensorCwiseBinaryOp>::type Nested;
     typedef typename Eigen::internal::traits<TensorCwiseBinaryOp>::StorageKind StorageKind;
     typedef typename Eigen::internal::traits<TensorCwiseBinaryOp>::Index Index;
@@ -234,7 +225,6 @@ struct traits<TensorSelectOp<IfXprType, ThenXprType, ElseXprType> >
 {
   typedef typename traits<ThenXprType>::Scalar Scalar;
   typedef traits<ThenXprType> XprTraits;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename promote_storage_type<typename traits<ThenXprType>::StorageKind,
                                         typename traits<ElseXprType>::StorageKind>::ret StorageKind;
   typedef typename promote_index_type<typename traits<ElseXprType>::Index,
@@ -266,12 +256,9 @@ class TensorSelectOp : public TensorBase<TensorSelectOp<IfXprType, ThenXprType,
 {
   public:
     typedef typename Eigen::internal::traits<TensorSelectOp>::Scalar Scalar;
-    typedef typename Eigen::internal::traits<TensorSelectOp>::Packet Packet;
     typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
     typedef typename internal::promote_storage_type<typename ThenXprType::CoeffReturnType,
                                                     typename ElseXprType::CoeffReturnType>::ret CoeffReturnType;
-    typedef typename internal::promote_storage_type<typename ThenXprType::PacketReturnType,
-                                                    typename ElseXprType::PacketReturnType>::ret PacketReturnType;
     typedef typename Eigen::internal::nested<TensorSelectOp>::type Nested;
     typedef typename Eigen::internal::traits<TensorSelectOp>::StorageKind StorageKind;
     typedef typename Eigen::internal::traits<TensorSelectOp>::Index Index;
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorFixedSize.h b/unsupported/Eigen/CXX11/src/Tensor/TensorFixedSize.h
index 70282dd83..9c0ed43b7 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorFixedSize.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorFixedSize.h
@@ -33,7 +33,6 @@ class TensorFixedSize : public TensorBase<TensorFixedSize<Scalar_, Dimensions_,
     typedef typename internal::traits<Self>::StorageKind StorageKind;
     typedef typename internal::traits<Self>::Index Index;
     typedef Scalar_ Scalar;
-    typedef typename internal::packet_traits<Scalar>::type Packet;
     typedef typename NumTraits<Scalar>::Real RealScalar;
     typedef typename Base::CoeffReturnType CoeffReturnType;
 
@@ -41,7 +40,6 @@ class TensorFixedSize : public TensorBase<TensorFixedSize<Scalar_, Dimensions_,
 
     enum {
       IsAligned = bool(EIGEN_MAX_ALIGN_BYTES>0),
-      PacketAccess = (internal::packet_traits<Scalar>::size > 1),
       Layout = Options_ & RowMajor ? RowMajor : ColMajor,
       CoordAccess = true,
       RawAccess = true
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorForcedEval.h b/unsupported/Eigen/CXX11/src/Tensor/TensorForcedEval.h
index 58b864787..14f480901 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorForcedEval.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorForcedEval.h
@@ -26,7 +26,6 @@ struct traits<TensorForcedEvalOp<XprType> >
   // Type promotion to handle the case where the types of the lhs and the rhs are different.
   typedef typename XprType::Scalar Scalar;
   typedef traits<XprType> XprTraits;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename traits<XprType>::StorageKind StorageKind;
   typedef typename traits<XprType>::Index Index;
   typedef typename XprType::Nested Nested;
@@ -60,10 +59,8 @@ class TensorForcedEvalOp : public TensorBase<TensorForcedEvalOp<XprType> >
 {
   public:
   typedef typename Eigen::internal::traits<TensorForcedEvalOp>::Scalar Scalar;
-  typedef typename Eigen::internal::traits<TensorForcedEvalOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename internal::remove_const<typename XprType::CoeffReturnType>::type CoeffReturnType;
-  typedef typename internal::remove_const<typename XprType::PacketReturnType>::type PacketReturnType;
   typedef typename Eigen::internal::nested<TensorForcedEvalOp>::type Nested;
   typedef typename Eigen::internal::traits<TensorForcedEvalOp>::StorageKind StorageKind;
   typedef typename Eigen::internal::traits<TensorForcedEvalOp>::Index Index;
@@ -85,7 +82,6 @@ struct TensorEvaluator<const TensorForcedEvalOp<ArgType>, Device>
 {
   typedef TensorForcedEvalOp<ArgType> XprType;
   typedef typename ArgType::Scalar Scalar;
-  typedef typename ArgType::Packet Packet;
   typedef typename TensorEvaluator<ArgType, Device>::Dimensions Dimensions;
 
   enum {
@@ -101,7 +97,7 @@ struct TensorEvaluator<const TensorForcedEvalOp<ArgType>, Device>
 
   typedef typename XprType::Index Index;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC const Dimensions& dimensions() const { return m_impl.dimensions(); }
 
@@ -133,7 +129,7 @@ struct TensorEvaluator<const TensorForcedEvalOp<ArgType>, Device>
   template<int LoadMode>
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE PacketReturnType packet(Index index) const
   {
-    return internal::ploadt<Packet, LoadMode>(m_buffer + index);
+    return internal::ploadt<PacketReturnType, LoadMode>(m_buffer + index);
   }
 
   EIGEN_DEVICE_FUNC Scalar* data() const { return m_buffer; }
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorFunctors.h b/unsupported/Eigen/CXX11/src/Tensor/TensorFunctors.h
index 528909688..b24f06df8 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorFunctors.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorFunctors.h
@@ -149,11 +149,11 @@ template <typename T> struct MaxReducer
   }
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE T initialize() const {
-    return -(std::numeric_limits<T>::max)();
+    return Eigen::NumTraits<T>::lowest();
   }
   template <typename Packet>
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE Packet initializePacket() const {
-    return pset1<Packet>(-(std::numeric_limits<T>::max)());
+    return pset1<Packet>(initialize());
   }
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE T finalize(const T accum) const {
     return accum;
@@ -182,11 +182,11 @@ template <typename T> struct MinReducer
   }
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE T initialize() const {
-    return (std::numeric_limits<T>::max)();
+    return Eigen::NumTraits<T>::highest();
   }
   template <typename Packet>
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE Packet initializePacket() const {
-    return pset1<Packet>((std::numeric_limits<T>::max)());
+    return pset1<Packet>(initialize());
   }
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE T finalize(const T accum) const {
     return accum;
@@ -722,6 +722,7 @@ template <> class NormalRandomGenerator<std::complex<double> > {
 
 template <typename T> class NormalRandomGenerator {
  public:
+  static const bool PacketAccess = false;
   NormalRandomGenerator(bool deterministic = true) : m_deterministic(deterministic) {}
 
  private:
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorGenerator.h b/unsupported/Eigen/CXX11/src/Tensor/TensorGenerator.h
index 96f74b992..e4154bd0b 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorGenerator.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorGenerator.h
@@ -25,7 +25,6 @@ struct traits<TensorGeneratorOp<Generator, XprType> > : public traits<XprType>
 {
   typedef typename XprType::Scalar Scalar;
   typedef traits<XprType> XprTraits;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename XprTraits::StorageKind StorageKind;
   typedef typename XprTraits::Index Index;
   typedef typename XprType::Nested Nested;
@@ -55,10 +54,8 @@ class TensorGeneratorOp : public TensorBase<TensorGeneratorOp<Generator, XprType
 {
   public:
   typedef typename Eigen::internal::traits<TensorGeneratorOp>::Scalar Scalar;
-  typedef typename Eigen::internal::traits<TensorGeneratorOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
   typedef typename Eigen::internal::nested<TensorGeneratorOp>::type Nested;
   typedef typename Eigen::internal::traits<TensorGeneratorOp>::StorageKind StorageKind;
   typedef typename Eigen::internal::traits<TensorGeneratorOp>::Index Index;
@@ -88,10 +85,11 @@ struct TensorEvaluator<const TensorGeneratorOp<Generator, ArgType>, Device>
   typedef typename TensorEvaluator<ArgType, Device>::Dimensions Dimensions;
   static const int NumDims = internal::array_size<Dimensions>::value;
   typedef typename XprType::Scalar Scalar;
-
+  typedef typename XprType::CoeffReturnType CoeffReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
   enum {
     IsAligned = false,
-    PacketAccess = (internal::packet_traits<Scalar>::size > 1),
+    PacketAccess = (internal::unpacket_traits<PacketReturnType>::size > 1),
     BlockAccess = false,
     Layout = TensorEvaluator<ArgType, Device>::Layout,
     CoordAccess = false,  // to be implemented
@@ -117,9 +115,6 @@ struct TensorEvaluator<const TensorGeneratorOp<Generator, ArgType>, Device>
     }
   }
 
-  typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
-
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Dimensions& dimensions() const { return m_dimensions; }
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE bool evalSubExprsIfNeeded(Scalar* /*data*/) {
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorImagePatch.h b/unsupported/Eigen/CXX11/src/Tensor/TensorImagePatch.h
index bc6021c9e..0008f9890 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorImagePatch.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorImagePatch.h
@@ -32,7 +32,6 @@ struct traits<TensorImagePatchOp<Rows, Cols, XprType> > : public traits<XprType>
 {
   typedef typename internal::remove_const<typename XprType::Scalar>::type Scalar;
   typedef traits<XprType> XprTraits;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename XprTraits::StorageKind StorageKind;
   typedef typename XprTraits::Index Index;
   typedef typename XprType::Nested Nested;
@@ -60,10 +59,8 @@ class TensorImagePatchOp : public TensorBase<TensorImagePatchOp<Rows, Cols, XprT
 {
   public:
   typedef typename Eigen::internal::traits<TensorImagePatchOp>::Scalar Scalar;
-  typedef typename Eigen::internal::traits<TensorImagePatchOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
   typedef typename Eigen::internal::nested<TensorImagePatchOp>::type Nested;
   typedef typename Eigen::internal::traits<TensorImagePatchOp>::StorageKind StorageKind;
   typedef typename Eigen::internal::traits<TensorImagePatchOp>::Index Index;
@@ -311,7 +308,7 @@ struct TensorEvaluator<const TensorImagePatchOp<Rows, Cols, ArgType>, Device>
   }
 
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Dimensions& dimensions() const { return m_dimensions; }
 
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorInflation.h b/unsupported/Eigen/CXX11/src/Tensor/TensorInflation.h
index 2798956ae..368e6f685 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorInflation.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorInflation.h
@@ -25,7 +25,6 @@ struct traits<TensorInflationOp<Strides, XprType> > : public traits<XprType>
 {
   typedef typename XprType::Scalar Scalar;
   typedef traits<XprType> XprTraits;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename XprTraits::StorageKind StorageKind;
   typedef typename XprTraits::Index Index;
   typedef typename XprType::Nested Nested;
@@ -53,10 +52,8 @@ class TensorInflationOp : public TensorBase<TensorInflationOp<Strides, XprType>,
 {
   public:
   typedef typename Eigen::internal::traits<TensorInflationOp>::Scalar Scalar;
-  typedef typename Eigen::internal::traits<TensorInflationOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
   typedef typename Eigen::internal::nested<TensorInflationOp>::type Nested;
   typedef typename Eigen::internal::traits<TensorInflationOp>::StorageKind StorageKind;
   typedef typename Eigen::internal::traits<TensorInflationOp>::Index Index;
@@ -128,7 +125,8 @@ struct TensorEvaluator<const TensorInflationOp<Strides, ArgType>, Device>
 
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
+
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Dimensions& dimensions() const { return m_dimensions; }
 
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorLayoutSwap.h b/unsupported/Eigen/CXX11/src/Tensor/TensorLayoutSwap.h
index a37516974..9b85914ff 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorLayoutSwap.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorLayoutSwap.h
@@ -40,7 +40,6 @@ struct traits<TensorLayoutSwapOp<XprType> > : public traits<XprType>
 {
   typedef typename XprType::Scalar Scalar;
   typedef traits<XprType> XprTraits;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename XprTraits::StorageKind StorageKind;
   typedef typename XprTraits::Index Index;
   typedef typename XprType::Nested Nested;
@@ -70,10 +69,8 @@ class TensorLayoutSwapOp : public TensorBase<TensorLayoutSwapOp<XprType>, WriteA
 {
   public:
   typedef typename Eigen::internal::traits<TensorLayoutSwapOp>::Scalar Scalar;
-  typedef typename Eigen::internal::traits<TensorLayoutSwapOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename internal::remove_const<typename XprType::CoeffReturnType>::type CoeffReturnType;
-  typedef typename internal::remove_const<typename XprType::PacketReturnType>::type PacketReturnType;
   typedef typename Eigen::internal::nested<TensorLayoutSwapOp>::type Nested;
   typedef typename Eigen::internal::traits<TensorLayoutSwapOp>::StorageKind StorageKind;
   typedef typename Eigen::internal::traits<TensorLayoutSwapOp>::Index Index;
@@ -136,7 +133,7 @@ struct TensorEvaluator<const TensorLayoutSwapOp<ArgType>, Device>
 
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Dimensions& dimensions() const { return m_dimensions; }
 
@@ -190,7 +187,7 @@ template<typename ArgType, typename Device>
   typedef typename XprType::Index Index;
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE CoeffReturnType& coeffRef(Index index)
   {
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorMap.h b/unsupported/Eigen/CXX11/src/Tensor/TensorMap.h
index 4a199cdd8..9ebd9172b 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorMap.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorMap.h
@@ -28,7 +28,6 @@ template<typename PlainObjectType, int Options_> class TensorMap : public Tensor
     typedef typename internal::traits<PlainObjectType>::StorageKind StorageKind;
     typedef typename internal::traits<PlainObjectType>::Index Index;
     typedef typename internal::traits<PlainObjectType>::Scalar Scalar;
-    typedef typename internal::packet_traits<Scalar>::type Packet;
     typedef typename NumTraits<Scalar>::Real RealScalar;
     typedef typename Base::CoeffReturnType CoeffReturnType;
 
@@ -47,7 +46,6 @@ template<typename PlainObjectType, int Options_> class TensorMap : public Tensor
 
     enum {
       IsAligned = ((int(Options_)&Aligned)==Aligned),
-      PacketAccess = (internal::packet_traits<Scalar>::size > 1),
       Layout = PlainObjectType::Layout,
       CoordAccess = true,
       RawAccess = true
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorMorphing.h b/unsupported/Eigen/CXX11/src/Tensor/TensorMorphing.h
index e867e450e..afde7b3d2 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorMorphing.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorMorphing.h
@@ -25,7 +25,6 @@ struct traits<TensorReshapingOp<NewDimensions, XprType> > : public traits<XprTyp
 {
   typedef typename XprType::Scalar Scalar;
   typedef traits<XprType> XprTraits;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename XprTraits::StorageKind StorageKind;
   typedef typename XprTraits::Index Index;
   typedef typename XprType::Nested Nested;
@@ -55,10 +54,8 @@ class TensorReshapingOp : public TensorBase<TensorReshapingOp<NewDimensions, Xpr
 {
   public:
   typedef typename Eigen::internal::traits<TensorReshapingOp>::Scalar Scalar;
-  typedef typename Eigen::internal::traits<TensorReshapingOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename internal::remove_const<typename XprType::CoeffReturnType>::type CoeffReturnType;
-  typedef typename internal::remove_const<typename XprType::PacketReturnType>::type PacketReturnType;
   typedef typename Eigen::internal::nested<TensorReshapingOp>::type Nested;
   typedef typename Eigen::internal::traits<TensorReshapingOp>::StorageKind StorageKind;
   typedef typename Eigen::internal::traits<TensorReshapingOp>::Index Index;
@@ -124,7 +121,7 @@ struct TensorEvaluator<const TensorReshapingOp<NewDimensions, ArgType>, Device>
   typedef typename XprType::Index Index;
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Dimensions& dimensions() const { return m_dimensions; }
 
@@ -181,7 +178,7 @@ template<typename NewDimensions, typename ArgType, typename Device>
   typedef typename XprType::Index Index;
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE CoeffReturnType& coeffRef(Index index)
   {
@@ -208,7 +205,6 @@ struct traits<TensorSlicingOp<StartIndices, Sizes, XprType> > : public traits<Xp
 {
   typedef typename XprType::Scalar Scalar;
   typedef traits<XprType> XprTraits;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename XprTraits::StorageKind StorageKind;
   typedef typename XprTraits::Index Index;
   typedef typename XprType::Nested Nested;
@@ -238,10 +234,8 @@ class TensorSlicingOp : public TensorBase<TensorSlicingOp<StartIndices, Sizes, X
 {
   public:
   typedef typename Eigen::internal::traits<TensorSlicingOp>::Scalar Scalar;
-  typedef typename Eigen::internal::traits<TensorSlicingOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
   typedef typename Eigen::internal::nested<TensorSlicingOp>::type Nested;
   typedef typename Eigen::internal::traits<TensorSlicingOp>::StorageKind StorageKind;
   typedef typename Eigen::internal::traits<TensorSlicingOp>::Index Index;
@@ -361,7 +355,7 @@ struct TensorEvaluator<const TensorSlicingOp<StartIndices, Sizes, ArgType>, Devi
   typedef typename XprType::Index Index;
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
   typedef Sizes Dimensions;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Dimensions& dimensions() const { return m_dimensions; }
@@ -549,7 +543,7 @@ struct TensorEvaluator<TensorSlicingOp<StartIndices, Sizes, ArgType>, Device>
   typedef typename XprType::Index Index;
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
   typedef Sizes Dimensions;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE CoeffReturnType& coeffRef(Index index)
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorPadding.h b/unsupported/Eigen/CXX11/src/Tensor/TensorPadding.h
index eaaf4dc86..a595a0175 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorPadding.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorPadding.h
@@ -25,7 +25,6 @@ struct traits<TensorPaddingOp<PaddingDimensions, XprType> > : public traits<XprT
 {
   typedef typename XprType::Scalar Scalar;
   typedef traits<XprType> XprTraits;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename XprTraits::StorageKind StorageKind;
   typedef typename XprTraits::Index Index;
   typedef typename XprType::Nested Nested;
@@ -55,10 +54,8 @@ class TensorPaddingOp : public TensorBase<TensorPaddingOp<PaddingDimensions, Xpr
 {
   public:
   typedef typename Eigen::internal::traits<TensorPaddingOp>::Scalar Scalar;
-  typedef typename Eigen::internal::traits<TensorPaddingOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
   typedef typename Eigen::internal::nested<TensorPaddingOp>::type Nested;
   typedef typename Eigen::internal::traits<TensorPaddingOp>::StorageKind StorageKind;
   typedef typename Eigen::internal::traits<TensorPaddingOp>::Index Index;
@@ -134,7 +131,7 @@ struct TensorEvaluator<const TensorPaddingOp<PaddingDimensions, ArgType>, Device
 
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Dimensions& dimensions() const { return m_dimensions; }
 
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorPatch.h b/unsupported/Eigen/CXX11/src/Tensor/TensorPatch.h
index 57b716fd6..0bf460f4e 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorPatch.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorPatch.h
@@ -25,7 +25,6 @@ struct traits<TensorPatchOp<PatchDim, XprType> > : public traits<XprType>
 {
   typedef typename XprType::Scalar Scalar;
   typedef traits<XprType> XprTraits;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename XprTraits::StorageKind StorageKind;
   typedef typename XprTraits::Index Index;
   typedef typename XprType::Nested Nested;
@@ -55,10 +54,8 @@ class TensorPatchOp : public TensorBase<TensorPatchOp<PatchDim, XprType>, ReadOn
 {
   public:
   typedef typename Eigen::internal::traits<TensorPatchOp>::Scalar Scalar;
-  typedef typename Eigen::internal::traits<TensorPatchOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
   typedef typename Eigen::internal::nested<TensorPatchOp>::type Nested;
   typedef typename Eigen::internal::traits<TensorPatchOp>::StorageKind StorageKind;
   typedef typename Eigen::internal::traits<TensorPatchOp>::Index Index;
@@ -141,7 +138,7 @@ struct TensorEvaluator<const TensorPatchOp<PatchDim, ArgType>, Device>
   }
 
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Dimensions& dimensions() const { return m_dimensions; }
 
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorReduction.h b/unsupported/Eigen/CXX11/src/Tensor/TensorReduction.h
index d01a63ccb..2d7fb80d4 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorReduction.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorReduction.h
@@ -26,7 +26,6 @@ struct traits<TensorReductionOp<Op, Dims, XprType> >
 {
   typedef traits<XprType> XprTraits;
   typedef typename XprTraits::Scalar Scalar;
-  typedef typename internal::packet_traits<Scalar>::type Packet;
   typedef typename XprTraits::StorageKind StorageKind;
   typedef typename XprTraits::Index Index;
   typedef typename XprType::Nested Nested;
@@ -222,121 +221,118 @@ struct FullReducer {
 
 #ifdef EIGEN_USE_THREADS
 // Multithreaded full reducers
-template <typename Eval, typename Op, bool Vectorizable = (Eval::InputPacketAccess & Op::PacketAccess)>
+template <typename Self, typename Op,
+          bool vectorizable = (Self::InputPacketAccess & Op::PacketAccess)>
 struct FullReducerShard {
-  static void run(const Eval& eval, typename Eval::Index firstIndex, typename Eval::Index numValuesToReduce, Op& reducer, FullReducerShard* shard) {
-
-    shard->saccum = reducer.initialize();
-    for (typename Eval::Index j = 0; j < numValuesToReduce; ++j) {
-      reducer.reduce(eval.m_impl.coeff(firstIndex + j), &shard->saccum);
-    }
+  static EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE void run(const Self& self, typename Self::Index firstIndex,
+                  typename Self::Index numValuesToReduce, Op& reducer,
+                  typename Self::CoeffReturnType* output) {
+    *output = InnerMostDimReducer<Self, Op, vectorizable>::reduce(
+        self, firstIndex, numValuesToReduce, reducer);
   }
-
-  typename Eval::CoeffReturnType saccum;
 };
 
-template <typename Eval, typename Op>
-struct FullReducerShard<Eval, Op, true> {
-  static void run(const Eval& eval, typename Eval::Index firstIndex, typename Eval::Index numValuesToReduce, Op& reducer, FullReducerShard* shard) {
-
-    const int packetSize = internal::unpacket_traits<typename Eval::PacketReturnType>::size;
-    const typename Eval::Index VectorizedSize = (numValuesToReduce / packetSize) * packetSize;
-
-    shard->paccum = reducer.template initializePacket<typename Eval::PacketReturnType>();
-    for (typename Eval::Index j = 0; j < VectorizedSize; j += packetSize) {
-      reducer.reducePacket(eval.m_impl.template packet<Unaligned>(firstIndex + j), &shard->paccum);
-    }
-    shard->saccum = reducer.initialize();
-    for (typename Eval::Index j = VectorizedSize; j < numValuesToReduce; ++j) {
-      reducer.reduce(eval.m_impl.coeff(firstIndex + j), &shard->saccum);
-    }
-  }
-
-  typename Eval::PacketReturnType paccum;
-  typename Eval::CoeffReturnType saccum;
-};
-
-
 template <typename Self, typename Op>
 struct FullReducer<Self, Op, ThreadPoolDevice, false> {
   static const bool HasOptimizedImplementation = !Op::IsStateful;
+  static const int PacketSize =
+      unpacket_traits<typename Self::PacketReturnType>::size;
 
   // launch one reducer per thread and accumulate the result.
-  static void run(const Self& self, Op& reducer, const ThreadPoolDevice& device, typename Self::CoeffReturnType* output) {
+  static void run(const Self& self, Op& reducer, const ThreadPoolDevice& device,
+                  typename Self::CoeffReturnType* output) {
     typedef typename Self::Index Index;
     const Index num_coeffs = array_prod(self.m_impl.dimensions());
-    const Index blocksize = std::floor<Index>(static_cast<float>(num_coeffs)/device.numThreads());
-    const Index numblocks = blocksize > 0 ? num_coeffs / blocksize : 0;
-    eigen_assert(num_coeffs >= numblocks * blocksize);
-
-    std::vector<Notification*> results;
-    results.reserve(numblocks);
-    std::vector<FullReducerShard<Self, Op, false> > shards;
-    shards.resize(numblocks);
-    for (Index i = 0; i < numblocks; ++i) {
-      results.push_back(device.enqueue(&FullReducerShard<Self, Op, false>::run, self, i*blocksize, blocksize, reducer, &shards[i]));
+    if (num_coeffs == 0) {
+      *output = reducer.finalize(reducer.initialize());
+      return;
     }
-
-    FullReducerShard<Self, Op, false> finalShard;
-    if (numblocks * blocksize < num_coeffs) {
-      FullReducerShard<Self, Op, false>::run(self, numblocks * blocksize, num_coeffs - numblocks * blocksize, reducer, &finalShard);
+    const int num_threads = device.numThreads();
+    if (num_threads == 1) {
+      *output = InnerMostDimReducer<Self, Op, false>::reduce(self, 0, num_coeffs, reducer);
+      return;
     } else {
-      finalShard.saccum = reducer.initialize();
-    }
+      const Index blocksize = std::floor<Index>(static_cast<float>(num_coeffs) / num_threads);
+      const Index numblocks = blocksize > 0 ? num_coeffs / blocksize : 0;
+      eigen_assert(num_coeffs >= numblocks * blocksize);
 
-    for (Index i = 0; i < numblocks; ++i) {
-      wait_until_ready(results[i]);
-      delete results[i];
-    }
+      MaxSizeVector<Notification*> results(numblocks);
+      MaxSizeVector<typename Self::CoeffReturnType> shards(numblocks, reducer.initialize());
+      for (Index i = 0; i < numblocks; ++i) {
+        results.push_back(
+            device.enqueue(&FullReducerShard<Self, Op, false>::run, self,
+                           i * blocksize, blocksize, reducer, &shards[i]));
+      }
 
-    for (Index i = 0; i < numblocks; ++i) {
-      reducer.reduce(shards[i].saccum, &finalShard.saccum);
+      typename Self::CoeffReturnType finalShard;
+      if (numblocks * blocksize < num_coeffs) {
+        finalShard = InnerMostDimReducer<Self, Op, false>::reduce(
+            self, numblocks * blocksize, num_coeffs - numblocks * blocksize, reducer);
+      } else {
+        finalShard = reducer.initialize();
+      }
+      for (Index i = 0; i < numblocks; ++i) {
+        wait_until_ready(results[i]);
+        delete results[i];
+      }
+      for (Index i = 0; i < numblocks; ++i) {
+        reducer.reduce(shards[i], &finalShard);
+      }
+      *output = reducer.finalize(finalShard);
     }
-    *output = reducer.finalize(finalShard.saccum);
   }
 };
 
 template <typename Self, typename Op>
 struct FullReducer<Self, Op, ThreadPoolDevice, true> {
   static const bool HasOptimizedImplementation = !Op::IsStateful;
+  static const int PacketSize =
+      unpacket_traits<typename Self::PacketReturnType>::size;
 
   // launch one reducer per thread and accumulate the result.
-  static void run(const Self& self, Op& reducer, const ThreadPoolDevice& device, typename Self::CoeffReturnType* output) {
+  static void run(const Self& self, Op& reducer, const ThreadPoolDevice& device,
+                  typename Self::CoeffReturnType* output) {
     typedef typename Self::Index Index;
     const Index num_coeffs = array_prod(self.m_impl.dimensions());
-    const Index blocksize = std::floor<Index>(static_cast<float>(num_coeffs)/device.numThreads());
+    if (num_coeffs == 0) {
+      *output = reducer.finalize(reducer.initialize());
+      return;
+    }
+    const int num_threads = device.numThreads();
+    if (num_threads == 1) {
+      *output = InnerMostDimReducer<Self, Op, true>::reduce(self, 0, num_coeffs, reducer);
+      return;
+    }
+    const Index blocksize = std::floor<Index>(static_cast<float>(num_coeffs) / num_threads);
     const Index numblocks = blocksize > 0 ? num_coeffs / blocksize : 0;
     eigen_assert(num_coeffs >= numblocks * blocksize);
 
-    std::vector<Notification*> results;
-    results.reserve(numblocks);
-    std::vector<FullReducerShard<Self, Op, true> > shards;
-    shards.resize(numblocks);
+    MaxSizeVector<Notification*> results(numblocks);
+    MaxSizeVector<typename Self::CoeffReturnType> shards(numblocks, reducer.initialize());
     for (Index i = 0; i < numblocks; ++i) {
-      results.push_back(device.enqueue(&FullReducerShard<Self, Op, true>::run, self, i*blocksize, blocksize, reducer, &shards[i]));
+      results.push_back(device.enqueue(&FullReducerShard<Self, Op, true>::run,
+                                       self, i * blocksize, blocksize, reducer,
+                                       &shards[i]));
     }
-
-    FullReducerShard<Self, Op, true> finalShard;
+    typename Self::CoeffReturnType finalShard;
     if (numblocks * blocksize < num_coeffs) {
-      FullReducerShard<Self, Op, true>::run(self, numblocks * blocksize, num_coeffs - numblocks * blocksize, reducer, &finalShard);
+      finalShard = InnerMostDimReducer<Self, Op, true>::reduce(
+          self, numblocks * blocksize, num_coeffs - numblocks * blocksize, reducer);
     } else {
-      finalShard.paccum = reducer.template initializePacket<typename Self::PacketReturnType>();
-      finalShard.saccum = reducer.initialize();
+      finalShard = reducer.initialize();
     }
 
     for (Index i = 0; i < numblocks; ++i) {
       wait_until_ready(results[i]);
       delete results[i];
     }
-
     for (Index i = 0; i < numblocks; ++i) {
-      reducer.reducePacket(shards[i].paccum, &finalShard.paccum);
-      reducer.reduce(shards[i].saccum, &finalShard.saccum);
+      reducer.reduce(shards[i], &finalShard);
     }
-
-    *output = reducer.finalizeBoth(finalShard.saccum, finalShard.paccum);
+    *output = reducer.finalize(finalShard);
   }
 };
+
 #endif
 
 
@@ -381,10 +377,8 @@ template <typename Op, typename Dims, typename XprType>
 class TensorReductionOp : public TensorBase<TensorReductionOp<Op, Dims, XprType>, ReadOnlyAccessors> {
   public:
     typedef typename Eigen::internal::traits<TensorReductionOp>::Scalar Scalar;
-    typedef typename Eigen::internal::traits<TensorReductionOp>::Packet Packet;
     typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
     typedef typename internal::remove_const<typename XprType::CoeffReturnType>::type CoeffReturnType;
-    typedef typename internal::remove_const<typename XprType::PacketReturnType>::type PacketReturnType;
     typedef typename Eigen::internal::nested<TensorReductionOp>::type Nested;
     typedef typename Eigen::internal::traits<TensorReductionOp>::StorageKind StorageKind;
     typedef typename Eigen::internal::traits<TensorReductionOp>::Index Index;
@@ -509,7 +503,7 @@ struct TensorEvaluator<const TensorReductionOp<Op, Dims, ArgType>, Device>
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Dimensions& dimensions() const { return m_dimensions; }
 
   typedef typename internal::remove_const<typename XprType::CoeffReturnType>::type CoeffReturnType;
-  typedef typename internal::remove_const<typename XprType::PacketReturnType>::type PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_STRONG_INLINE EIGEN_DEVICE_FUNC bool evalSubExprsIfNeeded(CoeffReturnType* data) {
     m_impl.evalSubExprsIfNeeded(NULL);
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorRef.h b/unsupported/Eigen/CXX11/src/Tensor/TensorRef.h
index 57197d060..bc92d9e6d 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorRef.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorRef.h
@@ -125,7 +125,6 @@ template<typename PlainObjectType> class TensorRef : public TensorBase<TensorRef
     typedef typename internal::traits<PlainObjectType>::StorageKind StorageKind;
     typedef typename internal::traits<PlainObjectType>::Index Index;
     typedef typename internal::traits<PlainObjectType>::Scalar Scalar;
-    typedef typename internal::packet_traits<Scalar>::type Packet;
     typedef typename NumTraits<Scalar>::Real RealScalar;
     typedef typename Base::CoeffReturnType CoeffReturnType;
     typedef Scalar* PointerType;
@@ -358,9 +357,8 @@ struct TensorEvaluator<const TensorRef<Derived>, Device>
 {
   typedef typename Derived::Index Index;
   typedef typename Derived::Scalar Scalar;
-  typedef typename Derived::Packet Packet;
   typedef typename Derived::Scalar CoeffReturnType;
-  typedef typename Derived::Packet PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
   typedef typename Derived::Dimensions Dimensions;
 
   enum {
@@ -404,9 +402,8 @@ struct TensorEvaluator<TensorRef<Derived>, Device> : public TensorEvaluator<cons
 {
   typedef typename Derived::Index Index;
   typedef typename Derived::Scalar Scalar;
-  typedef typename Derived::Packet Packet;
   typedef typename Derived::Scalar CoeffReturnType;
-  typedef typename Derived::Packet PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
   typedef typename Derived::Dimensions Dimensions;
 
   typedef TensorEvaluator<const TensorRef<Derived>, Device> Base;
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorReverse.h b/unsupported/Eigen/CXX11/src/Tensor/TensorReverse.h
index 846f81e0f..96d92038c 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorReverse.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorReverse.h
@@ -25,7 +25,6 @@ struct traits<TensorReverseOp<ReverseDimensions,
 {
   typedef typename XprType::Scalar Scalar;
   typedef traits<XprType> XprTraits;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename XprTraits::StorageKind StorageKind;
   typedef typename XprTraits::Index Index;
   typedef typename XprType::Nested Nested;
@@ -55,10 +54,8 @@ class TensorReverseOp : public TensorBase<TensorReverseOp<ReverseDimensions,
 {
   public:
   typedef typename Eigen::internal::traits<TensorReverseOp>::Scalar Scalar;
-  typedef typename Eigen::internal::traits<TensorReverseOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
   typedef typename Eigen::internal::nested<TensorReverseOp>::type Nested;
   typedef typename Eigen::internal::traits<TensorReverseOp>::StorageKind
                                                                     StorageKind;
@@ -140,7 +137,7 @@ struct TensorEvaluator<const TensorReverseOp<ReverseDimensions, ArgType>, Device
 
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
   const Dimensions& dimensions() const { return m_dimensions; }
@@ -248,7 +245,7 @@ struct TensorEvaluator<TensorReverseOp<ReverseDimensions, ArgType>, Device>
 
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
   const Dimensions& dimensions() const { return this->m_dimensions; }
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorShuffling.h b/unsupported/Eigen/CXX11/src/Tensor/TensorShuffling.h
index c4adb7d4c..c19833ea5 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorShuffling.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorShuffling.h
@@ -25,7 +25,6 @@ struct traits<TensorShufflingOp<Shuffle, XprType> > : public traits<XprType>
 {
   typedef typename XprType::Scalar Scalar;
   typedef traits<XprType> XprTraits;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename XprTraits::StorageKind StorageKind;
   typedef typename XprTraits::Index Index;
   typedef typename XprType::Nested Nested;
@@ -55,10 +54,8 @@ class TensorShufflingOp : public TensorBase<TensorShufflingOp<Shuffle, XprType>
 {
   public:
   typedef typename Eigen::internal::traits<TensorShufflingOp>::Scalar Scalar;
-  typedef typename Eigen::internal::traits<TensorShufflingOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
   typedef typename Eigen::internal::nested<TensorShufflingOp>::type Nested;
   typedef typename Eigen::internal::traits<TensorShufflingOp>::StorageKind StorageKind;
   typedef typename Eigen::internal::traits<TensorShufflingOp>::Index Index;
@@ -149,7 +146,7 @@ struct TensorEvaluator<const TensorShufflingOp<Shuffle, ArgType>, Device>
   }
 
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Dimensions& dimensions() const { return m_dimensions; }
 
@@ -234,7 +231,7 @@ struct TensorEvaluator<TensorShufflingOp<Shuffle, ArgType>, Device>
   { }
 
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE CoeffReturnType& coeffRef(Index index)
   {
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorStriding.h b/unsupported/Eigen/CXX11/src/Tensor/TensorStriding.h
index 2c2eb6515..085f8fd3d 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorStriding.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorStriding.h
@@ -25,7 +25,6 @@ struct traits<TensorStridingOp<Strides, XprType> > : public traits<XprType>
 {
   typedef typename XprType::Scalar Scalar;
   typedef traits<XprType> XprTraits;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename XprTraits::StorageKind StorageKind;
   typedef typename XprTraits::Index Index;
   typedef typename XprType::Nested Nested;
@@ -55,10 +54,8 @@ class TensorStridingOp : public TensorBase<TensorStridingOp<Strides, XprType> >
 {
   public:
   typedef typename Eigen::internal::traits<TensorStridingOp>::Scalar Scalar;
-  typedef typename Eigen::internal::traits<TensorStridingOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
   typedef typename Eigen::internal::nested<TensorStridingOp>::type Nested;
   typedef typename Eigen::internal::traits<TensorStridingOp>::StorageKind StorageKind;
   typedef typename Eigen::internal::traits<TensorStridingOp>::Index Index;
@@ -147,7 +144,7 @@ struct TensorEvaluator<const TensorStridingOp<Strides, ArgType>, Device>
 
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Dimensions& dimensions() const { return m_dimensions; }
 
@@ -267,7 +264,8 @@ struct TensorEvaluator<TensorStridingOp<Strides, ArgType>, Device>
 
   typedef typename XprType::Index Index;
   typedef typename XprType::Scalar Scalar;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename XprType::CoeffReturnType CoeffReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE Scalar& coeffRef(Index index)
   {
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorVolumePatch.h b/unsupported/Eigen/CXX11/src/Tensor/TensorVolumePatch.h
index 04f4f8ffc..5bdfbad46 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorVolumePatch.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorVolumePatch.h
@@ -27,7 +27,6 @@ struct traits<TensorVolumePatchOp<Planes, Rows, Cols, XprType> > : public traits
 {
   typedef typename internal::remove_const<typename XprType::Scalar>::type Scalar;
   typedef traits<XprType> XprTraits;
-  typedef typename packet_traits<Scalar>::type Packet;
   typedef typename XprTraits::StorageKind StorageKind;
   typedef typename XprTraits::Index Index;
   typedef typename XprType::Nested Nested;
@@ -55,10 +54,8 @@ class TensorVolumePatchOp : public TensorBase<TensorVolumePatchOp<Planes, Rows,
 {
   public:
   typedef typename Eigen::internal::traits<TensorVolumePatchOp>::Scalar Scalar;
-  typedef typename Eigen::internal::traits<TensorVolumePatchOp>::Packet Packet;
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
   typedef typename Eigen::internal::nested<TensorVolumePatchOp>::type Nested;
   typedef typename Eigen::internal::traits<TensorVolumePatchOp>::StorageKind StorageKind;
   typedef typename Eigen::internal::traits<TensorVolumePatchOp>::Index Index;
@@ -340,7 +337,7 @@ struct TensorEvaluator<const TensorVolumePatchOp<Planes, Rows, Cols, ArgType>, D
   }
 
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename PacketType<CoeffReturnType, Device>::type PacketReturnType;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Dimensions& dimensions() const { return m_dimensions; }