diff --git a/Eigen/src/Core/AssignEvaluator.h b/Eigen/src/Core/AssignEvaluator.h
index 574f945d5..9dbf2c063 100644
--- a/Eigen/src/Core/AssignEvaluator.h
+++ b/Eigen/src/Core/AssignEvaluator.h
@@ -30,12 +30,12 @@ struct copy_using_evaluator_traits
   typedef typename DstEvaluator::XprType Dst;
   typedef typename Dst::Scalar DstScalar;
   // TODO recursively find best packet size
-  typedef typename packet_traits<DstScalar>::type DstPacket;
+  typedef typename packet_traits<DstScalar>::type PacketType;
   
   enum {
     DstFlags = DstEvaluator::Flags,
     SrcFlags = SrcEvaluator::Flags,
-    RequiredAlignment = unpacket_traits<DstPacket>::alignment
+    RequiredAlignment = unpacket_traits<PacketType>::alignment
   };
   
 public:
@@ -230,6 +230,7 @@ struct copy_using_evaluator_innervec_CompleteUnrolling
   // FIXME: this is not very clean, perhaps this information should be provided by the kernel?
   typedef typename Kernel::DstEvaluatorType DstEvaluatorType;
   typedef typename DstEvaluatorType::XprType DstXprType;
+  typedef typename Kernel::PacketType PacketType;
   
   enum {
     outer = Index / DstXprType::InnerSizeAtCompileTime,
@@ -239,8 +240,8 @@ struct copy_using_evaluator_innervec_CompleteUnrolling
 
   EIGEN_DEVICE_FUNC static EIGEN_STRONG_INLINE void run(Kernel &kernel)
   {
-    kernel.template assignPacketByOuterInner<Aligned, JointAlignment>(outer, inner);
-    enum { NextIndex = Index + packet_traits<typename DstXprType::Scalar>::size };
+    kernel.template assignPacketByOuterInner<Aligned, JointAlignment, PacketType>(outer, inner);
+    enum { NextIndex = Index + unpacket_traits<PacketType>::size };
     copy_using_evaluator_innervec_CompleteUnrolling<Kernel, NextIndex, Stop>::run(kernel);
   }
 };
@@ -254,10 +255,11 @@ struct copy_using_evaluator_innervec_CompleteUnrolling<Kernel, Stop, Stop>
 template<typename Kernel, int Index_, int Stop>
 struct copy_using_evaluator_innervec_InnerUnrolling
 {
+  typedef typename Kernel::PacketType PacketType;
   EIGEN_DEVICE_FUNC static EIGEN_STRONG_INLINE void run(Kernel &kernel, Index outer)
   {
-    kernel.template assignPacketByOuterInner<Aligned, Aligned>(outer, Index_);
-    enum { NextIndex = Index_ + packet_traits<typename Kernel::Scalar>::size };
+    kernel.template assignPacketByOuterInner<Aligned, Aligned, PacketType>(outer, Index_);
+    enum { NextIndex = Index_ + unpacket_traits<PacketType>::size };
     copy_using_evaluator_innervec_InnerUnrolling<Kernel, NextIndex, Stop>::run(kernel, outer);
   }
 };
@@ -366,13 +368,13 @@ struct dense_assignment_loop<Kernel, LinearVectorizedTraversal, NoUnrolling>
   {
     const Index size = kernel.size();
     typedef typename Kernel::Scalar Scalar;
-    typedef packet_traits<Scalar> PacketTraits;
+    typedef typename Kernel::PacketType PacketType;
     enum {
       requestedAlignment = Kernel::AssignmentTraits::RequiredAlignment,
-      packetSize = PacketTraits::size,
+      packetSize = unpacket_traits<PacketType>::size,
       dstIsAligned = int(Kernel::AssignmentTraits::DstAlignment)>=int(requestedAlignment),
-      dstAlignment = PacketTraits::AlignedOnScalar ? int(requestedAlignment)
-                                                   : int(Kernel::AssignmentTraits::DstAlignment),
+      dstAlignment = packet_traits<Scalar>::AlignedOnScalar ? int(requestedAlignment)
+                                                            : int(Kernel::AssignmentTraits::DstAlignment),
       srcAlignment = Kernel::AssignmentTraits::JointAlignment
     };
     const Index alignedStart = dstIsAligned ? 0 : internal::first_aligned<requestedAlignment>(&kernel.dstEvaluator().coeffRef(0), size);
@@ -381,7 +383,7 @@ struct dense_assignment_loop<Kernel, LinearVectorizedTraversal, NoUnrolling>
     unaligned_dense_assignment_loop<dstIsAligned!=0>::run(kernel, 0, alignedStart);
 
     for(Index index = alignedStart; index < alignedEnd; index += packetSize)
-      kernel.template assignPacket<dstAlignment, srcAlignment>(index);
+      kernel.template assignPacket<dstAlignment, srcAlignment, PacketType>(index);
 
     unaligned_dense_assignment_loop<>::run(kernel, alignedEnd, size);
   }
@@ -411,14 +413,15 @@ struct dense_assignment_loop<Kernel, LinearVectorizedTraversal, CompleteUnrollin
 template<typename Kernel>
 struct dense_assignment_loop<Kernel, InnerVectorizedTraversal, NoUnrolling>
 {
+  typedef typename Kernel::PacketType PacketType;
   EIGEN_DEVICE_FUNC static inline void run(Kernel &kernel)
   {
     const Index innerSize = kernel.innerSize();
     const Index outerSize = kernel.outerSize();
-    const Index packetSize = packet_traits<typename Kernel::Scalar>::size;
+    const Index packetSize = unpacket_traits<PacketType>::size;
     for(Index outer = 0; outer < outerSize; ++outer)
       for(Index inner = 0; inner < innerSize; inner+=packetSize)
-        kernel.template assignPacketByOuterInner<Aligned, Aligned>(outer, inner);
+        kernel.template assignPacketByOuterInner<Aligned, Aligned, PacketType>(outer, inner);
   }
 };
 
@@ -480,11 +483,11 @@ struct dense_assignment_loop<Kernel, SliceVectorizedTraversal, NoUnrolling>
   EIGEN_DEVICE_FUNC static inline void run(Kernel &kernel)
   {
     typedef typename Kernel::Scalar Scalar;
-    typedef packet_traits<Scalar> PacketTraits;
+    typedef typename Kernel::PacketType PacketType;
     enum {
-      packetSize = PacketTraits::size,
+      packetSize = unpacket_traits<PacketType>::size,
       requestedAlignment = int(Kernel::AssignmentTraits::RequiredAlignment),
-      alignable = PacketTraits::AlignedOnScalar || int(Kernel::AssignmentTraits::DstAlignment)>=sizeof(Scalar),
+      alignable = packet_traits<Scalar>::AlignedOnScalar || int(Kernel::AssignmentTraits::DstAlignment)>=sizeof(Scalar),
       dstIsAligned = int(Kernel::AssignmentTraits::DstAlignment)>=int(requestedAlignment),
       dstAlignment = alignable ? int(requestedAlignment)
                                : int(Kernel::AssignmentTraits::DstAlignment)
@@ -510,7 +513,7 @@ struct dense_assignment_loop<Kernel, SliceVectorizedTraversal, NoUnrolling>
 
       // do the vectorizable part of the assignment
       for(Index inner = alignedStart; inner<alignedEnd; inner+=packetSize)
-        kernel.template assignPacketByOuterInner<dstAlignment, Unaligned>(outer, inner);
+        kernel.template assignPacketByOuterInner<dstAlignment, Unaligned, PacketType>(outer, inner);
 
       // do the non-vectorizable part of the assignment
       for(Index inner = alignedEnd; inner<innerSize ; ++inner)
@@ -544,6 +547,7 @@ public:
   typedef typename DstEvaluatorType::Scalar Scalar;
   typedef typename DstEvaluatorType::StorageIndex StorageIndex;
   typedef copy_using_evaluator_traits<DstEvaluatorTypeT, SrcEvaluatorTypeT, Functor> AssignmentTraits;
+  typedef typename AssignmentTraits::PacketType PacketType;
   
   
   EIGEN_DEVICE_FUNC generic_dense_assignment_kernel(DstEvaluatorType &dst, const SrcEvaluatorType &src, const Functor &func, DstXprType& dstExpr)
@@ -588,24 +592,24 @@ public:
   }
   
   
-  template<int StoreMode, int LoadMode>
+  template<int StoreMode, int LoadMode, typename PacketType>
   EIGEN_DEVICE_FUNC void assignPacket(Index row, Index col)
   {
-    m_functor.template assignPacket<StoreMode>(&m_dst.coeffRef(row,col), m_src.template packet<LoadMode>(row,col));
+    m_functor.template assignPacket<StoreMode>(&m_dst.coeffRef(row,col), m_src.template packet<LoadMode,PacketType>(row,col));
   }
   
-  template<int StoreMode, int LoadMode>
+  template<int StoreMode, int LoadMode, typename PacketType>
   EIGEN_DEVICE_FUNC void assignPacket(Index index)
   {
-    m_functor.template assignPacket<StoreMode>(&m_dst.coeffRef(index), m_src.template packet<LoadMode>(index));
+    m_functor.template assignPacket<StoreMode>(&m_dst.coeffRef(index), m_src.template packet<LoadMode,PacketType>(index));
   }
   
-  template<int StoreMode, int LoadMode>
+  template<int StoreMode, int LoadMode, typename PacketType>
   EIGEN_DEVICE_FUNC void assignPacketByOuterInner(Index outer, Index inner)
   {
     Index row = rowIndexByOuterInner(outer, inner); 
     Index col = colIndexByOuterInner(outer, inner);
-    assignPacket<StoreMode,LoadMode>(row, col);
+    assignPacket<StoreMode,LoadMode,PacketType>(row, col);
   }
   
   EIGEN_DEVICE_FUNC static Index rowIndexByOuterInner(Index outer, Index inner)
diff --git a/Eigen/src/Core/CoreEvaluators.h b/Eigen/src/Core/CoreEvaluators.h
index a599a6a69..26df269a0 100644
--- a/Eigen/src/Core/CoreEvaluators.h
+++ b/Eigen/src/Core/CoreEvaluators.h
@@ -131,8 +131,6 @@ struct evaluator<PlainObjectBase<Derived> >
   typedef PlainObjectBase<Derived> PlainObjectType;
   typedef typename PlainObjectType::Scalar Scalar;
   typedef typename PlainObjectType::CoeffReturnType CoeffReturnType;
-  typedef typename PlainObjectType::PacketScalar PacketScalar;
-  typedef typename PlainObjectType::PacketReturnType PacketReturnType;
 
   enum {
     IsRowMajor = PlainObjectType::IsRowMajor,
@@ -182,36 +180,36 @@ struct evaluator<PlainObjectBase<Derived> >
     return const_cast<Scalar*>(m_data)[index];
   }
 
-  template<int LoadMode> 
-  PacketReturnType packet(Index row, Index col) const
+  template<int LoadMode, typename PacketType>
+  PacketType packet(Index row, Index col) const
   {
     if (IsRowMajor)
-      return ploadt<PacketScalar, LoadMode>(m_data + row * m_outerStride.value() + col);
+      return ploadt<PacketType, LoadMode>(m_data + row * m_outerStride.value() + col);
     else
-      return ploadt<PacketScalar, LoadMode>(m_data + row + col * m_outerStride.value());
+      return ploadt<PacketType, LoadMode>(m_data + row + col * m_outerStride.value());
   }
 
-  template<int LoadMode> 
-  PacketReturnType packet(Index index) const
+  template<int LoadMode, typename PacketType>
+  PacketType packet(Index index) const
   {
-    return ploadt<PacketScalar, LoadMode>(m_data + index);
+    return ploadt<PacketType, LoadMode>(m_data + index);
   }
 
-  template<int StoreMode> 
-  void writePacket(Index row, Index col, const PacketScalar& x)
+  template<int StoreMode,typename PacketType>
+  void writePacket(Index row, Index col, const PacketType& x)
   {
     if (IsRowMajor)
-      return pstoret<Scalar, PacketScalar, StoreMode>
+      return pstoret<Scalar, PacketType, StoreMode>
 	            (const_cast<Scalar*>(m_data) + row * m_outerStride.value() + col, x);
     else
-      return pstoret<Scalar, PacketScalar, StoreMode>
+      return pstoret<Scalar, PacketType, StoreMode>
                     (const_cast<Scalar*>(m_data) + row + col * m_outerStride.value(), x);
   }
 
-  template<int StoreMode> 
-  void writePacket(Index index, const PacketScalar& x)
+  template<int StoreMode, typename PacketType>
+  void writePacket(Index index, const PacketType& x)
   {
-    return pstoret<Scalar, PacketScalar, StoreMode>(const_cast<Scalar*>(m_data) + index, x);
+    return pstoret<Scalar, PacketType, StoreMode>(const_cast<Scalar*>(m_data) + index, x);
   }
 
 protected:
@@ -267,8 +265,6 @@ struct unary_evaluator<Transpose<ArgType>, IndexBased>
 
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketScalar PacketScalar;
-  typedef typename XprType::PacketReturnType PacketReturnType;
 
   EIGEN_DEVICE_FUNC CoeffReturnType coeff(Index row, Index col) const
   {
@@ -290,28 +286,28 @@ struct unary_evaluator<Transpose<ArgType>, IndexBased>
     return m_argImpl.coeffRef(index);
   }
 
-  template<int LoadMode>
-  PacketReturnType packet(Index row, Index col) const
+  template<int LoadMode, typename PacketType>
+  PacketType packet(Index row, Index col) const
   {
-    return m_argImpl.template packet<LoadMode>(col, row);
+    return m_argImpl.template packet<LoadMode,PacketType>(col, row);
   }
 
-  template<int LoadMode>
-  PacketReturnType packet(Index index) const
+  template<int LoadMode, typename PacketType>
+  PacketType packet(Index index) const
   {
-    return m_argImpl.template packet<LoadMode>(index);
+    return m_argImpl.template packet<LoadMode,PacketType>(index);
   }
 
-  template<int StoreMode> 
-  void writePacket(Index row, Index col, const PacketScalar& x)
+  template<int StoreMode, typename PacketType> 
+  void writePacket(Index row, Index col, const PacketType& x)
   {
-    m_argImpl.template writePacket<StoreMode>(col, row, x);
+    m_argImpl.template writePacket<StoreMode,PacketType>(col, row, x);
   }
 
-  template<int StoreMode> 
-  void writePacket(Index index, const PacketScalar& x)
+  template<int StoreMode, typename PacketType> 
+  void writePacket(Index index, const PacketType& x)
   {
-    m_argImpl.template writePacket<StoreMode>(index, x);
+    m_argImpl.template writePacket<StoreMode,PacketType>(index, x);
   }
 
 protected:
@@ -345,7 +341,6 @@ struct evaluator<CwiseNullaryOp<NullaryOp,PlainObjectType> >
   { }
 
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketScalar PacketScalar;
 
   EIGEN_DEVICE_FUNC CoeffReturnType coeff(Index row, Index col) const
   {
@@ -357,16 +352,16 @@ struct evaluator<CwiseNullaryOp<NullaryOp,PlainObjectType> >
     return m_functor(index);
   }
 
-  template<int LoadMode>
-  PacketScalar packet(Index row, Index col) const
+  template<int LoadMode, typename PacketType>
+  PacketType packet(Index row, Index col) const
   {
-    return m_functor.packetOp(row, col);
+    return m_functor.template packetOp<Index,PacketType>(row, col);
   }
 
-  template<int LoadMode>
-  PacketScalar packet(Index index) const
+  template<int LoadMode, typename PacketType>
+  PacketType packet(Index index) const
   {
-    return m_functor.packetOp(index);
+    return m_functor.template packetOp<Index,PacketType>(index);
   }
 
 protected:
@@ -395,7 +390,6 @@ struct unary_evaluator<CwiseUnaryOp<UnaryOp, ArgType>, IndexBased >
   { }
 
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketScalar PacketScalar;
 
   EIGEN_DEVICE_FUNC CoeffReturnType coeff(Index row, Index col) const
   {
@@ -407,16 +401,16 @@ struct unary_evaluator<CwiseUnaryOp<UnaryOp, ArgType>, IndexBased >
     return m_functor(m_argImpl.coeff(index));
   }
 
-  template<int LoadMode>
-  PacketScalar packet(Index row, Index col) const
+  template<int LoadMode, typename PacketType>
+  PacketType packet(Index row, Index col) const
   {
-    return m_functor.packetOp(m_argImpl.template packet<LoadMode>(row, col));
+    return m_functor.packetOp(m_argImpl.template packet<LoadMode, PacketType>(row, col));
   }
 
-  template<int LoadMode>
-  PacketScalar packet(Index index) const
+  template<int LoadMode, typename PacketType>
+  PacketType packet(Index index) const
   {
-    return m_functor.packetOp(m_argImpl.template packet<LoadMode>(index));
+    return m_functor.packetOp(m_argImpl.template packet<LoadMode, PacketType>(index));
   }
 
 protected:
@@ -469,7 +463,6 @@ struct binary_evaluator<CwiseBinaryOp<BinaryOp, Lhs, Rhs>, IndexBased, IndexBase
   { }
 
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketScalar PacketScalar;
 
   EIGEN_DEVICE_FUNC CoeffReturnType coeff(Index row, Index col) const
   {
@@ -481,18 +474,18 @@ struct binary_evaluator<CwiseBinaryOp<BinaryOp, Lhs, Rhs>, IndexBased, IndexBase
     return m_functor(m_lhsImpl.coeff(index), m_rhsImpl.coeff(index));
   }
 
-  template<int LoadMode>
-  PacketScalar packet(Index row, Index col) const
+  template<int LoadMode, typename PacketType>
+  PacketType packet(Index row, Index col) const
   {
-    return m_functor.packetOp(m_lhsImpl.template packet<LoadMode>(row, col),
-                              m_rhsImpl.template packet<LoadMode>(row, col));
+    return m_functor.packetOp(m_lhsImpl.template packet<LoadMode,PacketType>(row, col),
+                              m_rhsImpl.template packet<LoadMode,PacketType>(row, col));
   }
 
-  template<int LoadMode>
-  PacketScalar packet(Index index) const
+  template<int LoadMode, typename PacketType>
+  PacketType packet(Index index) const
   {
-    return m_functor.packetOp(m_lhsImpl.template packet<LoadMode>(index),
-                              m_rhsImpl.template packet<LoadMode>(index));
+    return m_functor.packetOp(m_lhsImpl.template packet<LoadMode,PacketType>(index),
+                              m_rhsImpl.template packet<LoadMode,PacketType>(index));
   }
 
 protected:
@@ -564,8 +557,6 @@ struct mapbase_evaluator : evaluator_base<Derived>
   typedef typename XprType::PointerType PointerType;
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketScalar PacketScalar;
-  typedef typename XprType::PacketReturnType PacketReturnType;
   
   enum {
     IsRowMajor = XprType::RowsAtCompileTime,
@@ -601,30 +592,30 @@ struct mapbase_evaluator : evaluator_base<Derived>
     return m_data[index * m_xpr.innerStride()];
   }
  
-  template<int LoadMode> 
-  PacketReturnType packet(Index row, Index col) const 
+  template<int LoadMode, typename PacketType> 
+  PacketType packet(Index row, Index col) const 
   {
     PointerType ptr = m_data + row * m_xpr.rowStride() + col * m_xpr.colStride();
-    return internal::ploadt<PacketScalar, LoadMode>(ptr);
+    return internal::ploadt<PacketType, LoadMode>(ptr);
   }
 
-  template<int LoadMode> 
-  PacketReturnType packet(Index index) const 
+  template<int LoadMode, typename PacketType> 
+  PacketType packet(Index index) const 
   {
-    return internal::ploadt<PacketScalar, LoadMode>(m_data + index * m_xpr.innerStride());
+    return internal::ploadt<PacketType, LoadMode>(m_data + index * m_xpr.innerStride());
   }
   
-  template<int StoreMode> 
-  void writePacket(Index row, Index col, const PacketScalar& x) 
+  template<int StoreMode, typename PacketType> 
+  void writePacket(Index row, Index col, const PacketType& x) 
   {
     PointerType ptr = m_data + row * m_xpr.rowStride() + col * m_xpr.colStride();
-    return internal::pstoret<Scalar, PacketScalar, StoreMode>(ptr, x);
+    return internal::pstoret<Scalar, PacketType, StoreMode>(ptr, x);
   }
   
-  template<int StoreMode> 
-  void writePacket(Index index, const PacketScalar& x) 
+  template<int StoreMode, typename PacketType> 
+  void writePacket(Index index, const PacketType& x) 
   {
-    internal::pstoret<Scalar, PacketScalar, StoreMode>(m_data + index * m_xpr.innerStride(), x);
+    internal::pstoret<Scalar, PacketType, StoreMode>(m_data + index * m_xpr.innerStride(), x);
   }
  
 protected:
@@ -770,8 +761,6 @@ struct unary_evaluator<Block<ArgType, BlockRows, BlockCols, InnerPanel>, IndexBa
  
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketScalar PacketScalar;
-  typedef typename XprType::PacketReturnType PacketReturnType;
 
   enum {
     RowsAtCompileTime = XprType::RowsAtCompileTime
@@ -797,31 +786,31 @@ struct unary_evaluator<Block<ArgType, BlockRows, BlockCols, InnerPanel>, IndexBa
     return coeffRef(RowsAtCompileTime == 1 ? 0 : index, RowsAtCompileTime == 1 ? index : 0);
   }
  
-  template<int LoadMode> 
-  PacketReturnType packet(Index row, Index col) const 
+  template<int LoadMode, typename PacketType> 
+  PacketType packet(Index row, Index col) const 
   { 
-    return m_argImpl.template packet<LoadMode>(m_startRow.value() + row, m_startCol.value() + col); 
+    return m_argImpl.template packet<LoadMode,PacketType>(m_startRow.value() + row, m_startCol.value() + col); 
   }
 
-  template<int LoadMode> 
-  PacketReturnType packet(Index index) const 
+  template<int LoadMode, typename PacketType> 
+  PacketType packet(Index index) const 
   { 
-    return packet<LoadMode>(RowsAtCompileTime == 1 ? 0 : index,
-                            RowsAtCompileTime == 1 ? index : 0);
+    return packet<LoadMode,PacketType>(RowsAtCompileTime == 1 ? 0 : index,
+                                       RowsAtCompileTime == 1 ? index : 0);
   }
   
-  template<int StoreMode> 
-  void writePacket(Index row, Index col, const PacketScalar& x) 
+  template<int StoreMode, typename PacketType> 
+  void writePacket(Index row, Index col, const PacketType& x) 
   { 
-    return m_argImpl.template writePacket<StoreMode>(m_startRow.value() + row, m_startCol.value() + col, x); 
+    return m_argImpl.template writePacket<StoreMode,PacketType>(m_startRow.value() + row, m_startCol.value() + col, x); 
   }
   
-  template<int StoreMode> 
-  void writePacket(Index index, const PacketScalar& x) 
+  template<int StoreMode, typename PacketType> 
+  void writePacket(Index index, const PacketType& x) 
   { 
-    return writePacket<StoreMode>(RowsAtCompileTime == 1 ? 0 : index,
-                                  RowsAtCompileTime == 1 ? index : 0,
-                                  x);
+    return writePacket<StoreMode,PacketType>(RowsAtCompileTime == 1 ? 0 : index,
+                                             RowsAtCompileTime == 1 ? index : 0,
+                                             x);
   }
  
 protected:
@@ -908,7 +897,6 @@ struct unary_evaluator<Replicate<ArgType, RowFactor, ColFactor> >
 {
   typedef Replicate<ArgType, RowFactor, ColFactor> XprType;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
   enum {
     Factor = (RowFactor==Dynamic || ColFactor==Dynamic) ? Dynamic : RowFactor*ColFactor
   };
@@ -953,8 +941,8 @@ struct unary_evaluator<Replicate<ArgType, RowFactor, ColFactor> >
     return m_argImpl.coeff(actual_index);
   }
 
-  template<int LoadMode>
-  PacketReturnType packet(Index row, Index col) const
+  template<int LoadMode, typename PacketType>
+  PacketType packet(Index row, Index col) const
   {
     const Index actual_row = internal::traits<XprType>::RowsAtCompileTime==1 ? 0
                            : RowFactor==1 ? row
@@ -963,17 +951,17 @@ struct unary_evaluator<Replicate<ArgType, RowFactor, ColFactor> >
                            : ColFactor==1 ? col
                            : col % m_cols.value();
 
-    return m_argImpl.template packet<LoadMode>(actual_row, actual_col);
+    return m_argImpl.template packet<LoadMode,PacketType>(actual_row, actual_col);
   }
   
-  template<int LoadMode>
-  PacketReturnType packet(Index index) const
+  template<int LoadMode, typename PacketType>
+  PacketType packet(Index index) const
   {
     const Index actual_index = internal::traits<XprType>::RowsAtCompileTime==1
                                   ? (ColFactor==1 ?  index : index%m_cols.value())
                                   : (RowFactor==1 ?  index : index%m_rows.value());
 
-    return m_argImpl.template packet<LoadMode>(actual_index);
+    return m_argImpl.template packet<LoadMode,PacketType>(actual_index);
   }
  
 protected:
@@ -1050,8 +1038,6 @@ struct evaluator_wrapper_base
 
   typedef typename ArgType::Scalar Scalar;
   typedef typename ArgType::CoeffReturnType CoeffReturnType;
-  typedef typename ArgType::PacketScalar PacketScalar;
-  typedef typename ArgType::PacketReturnType PacketReturnType;
 
   EIGEN_DEVICE_FUNC CoeffReturnType coeff(Index row, Index col) const
   {
@@ -1073,26 +1059,26 @@ struct evaluator_wrapper_base
     return m_argImpl.coeffRef(index);
   }
 
-  template<int LoadMode> 
-  PacketReturnType packet(Index row, Index col) const
+  template<int LoadMode, typename PacketType> 
+  PacketType packet(Index row, Index col) const
   {
-    return m_argImpl.template packet<LoadMode>(row, col);
+    return m_argImpl.template packet<LoadMode,PacketType>(row, col);
   }
 
-  template<int LoadMode> 
-  PacketReturnType packet(Index index) const
+  template<int LoadMode, typename PacketType> 
+  PacketType packet(Index index) const
   {
-    return m_argImpl.template packet<LoadMode>(index);
+    return m_argImpl.template packet<LoadMode,PacketType>(index);
   }
 
-  template<int StoreMode> 
-  void writePacket(Index row, Index col, const PacketScalar& x)
+  template<int StoreMode, typename PacketType> 
+  void writePacket(Index row, Index col, const PacketType& x)
   {
     m_argImpl.template writePacket<StoreMode>(row, col, x);
   }
 
-  template<int StoreMode> 
-  void writePacket(Index index, const PacketScalar& x)
+  template<int StoreMode, typename PacketType> 
+  void writePacket(Index index, const PacketType& x)
   {
     m_argImpl.template writePacket<StoreMode>(index, x);
   }
@@ -1127,7 +1113,7 @@ struct unary_evaluator<ArrayWrapper<TArgType> >
 // -------------------- Reverse --------------------
 
 // defined in Reverse.h:
-template<typename PacketScalar, bool ReversePacket> struct reverse_packet_cond;
+template<typename PacketType, bool ReversePacket> struct reverse_packet_cond;
 
 template<typename ArgType, int Direction>
 struct unary_evaluator<Reverse<ArgType, Direction> >
@@ -1136,17 +1122,12 @@ struct unary_evaluator<Reverse<ArgType, Direction> >
   typedef Reverse<ArgType, Direction> XprType;
   typedef typename XprType::Scalar Scalar;
   typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketScalar PacketScalar;
-  typedef typename XprType::PacketReturnType PacketReturnType;
 
   enum {
-    PacketSize = internal::packet_traits<Scalar>::size,
     IsRowMajor = XprType::IsRowMajor,
     IsColMajor = !IsRowMajor,
     ReverseRow = (Direction == Vertical)   || (Direction == BothDirections),
     ReverseCol = (Direction == Horizontal) || (Direction == BothDirections),
-    OffsetRow  = ReverseRow && IsColMajor ? PacketSize : 1,
-    OffsetCol  = ReverseCol && IsRowMajor ? PacketSize : 1,
     ReversePacket = (Direction == BothDirections)
                     || ((Direction == Vertical)   && IsColMajor)
                     || ((Direction == Horizontal) && IsRowMajor),
@@ -1163,7 +1144,6 @@ struct unary_evaluator<Reverse<ArgType, Direction> >
     
     Alignment = 0 // FIXME in some rare cases, Alignment could be preserved, like a Vector4f.
   };
-  typedef internal::reverse_packet_cond<PacketScalar,ReversePacket> reverse_packet;
 
   EIGEN_DEVICE_FUNC explicit unary_evaluator(const XprType& reverse)
     : m_argImpl(reverse.nestedExpression()),
@@ -1193,32 +1173,47 @@ struct unary_evaluator<Reverse<ArgType, Direction> >
     return m_argImpl.coeffRef(m_rows.value() * m_cols.value() - index - 1);
   }
 
-  template<int LoadMode>
-  PacketScalar packet(Index row, Index col) const
+  template<int LoadMode, typename PacketType>
+  PacketType packet(Index row, Index col) const
   {
-    return reverse_packet::run(m_argImpl.template packet<LoadMode>(
+    enum {
+      PacketSize = unpacket_traits<PacketType>::size,
+      OffsetRow  = ReverseRow && IsColMajor ? PacketSize : 1,
+      OffsetCol  = ReverseCol && IsRowMajor ? PacketSize : 1
+    };
+    typedef internal::reverse_packet_cond<PacketType,ReversePacket> reverse_packet;
+    return reverse_packet::run(m_argImpl.template packet<LoadMode,PacketType>(
                                   ReverseRow ? m_rows.value() - row - OffsetRow : row,
                                   ReverseCol ? m_cols.value() - col - OffsetCol : col));
   }
 
-  template<int LoadMode>
-  PacketScalar packet(Index index) const
+  template<int LoadMode, typename PacketType>
+  PacketType packet(Index index) const
   {
-    return preverse(m_argImpl.template packet<LoadMode>(m_rows.value() * m_cols.value() - index - PacketSize));
+    enum { PacketSize = unpacket_traits<PacketType>::size };
+    return preverse(m_argImpl.template packet<LoadMode,PacketType>(m_rows.value() * m_cols.value() - index - PacketSize));
   }
 
-  template<int LoadMode>
-  void writePacket(Index row, Index col, const PacketScalar& x)
+  template<int LoadMode, typename PacketType>
+  void writePacket(Index row, Index col, const PacketType& x)
   {
+    // FIXME we could factorize some code with packet(i,j)
+    enum {
+      PacketSize = unpacket_traits<PacketType>::size,
+      OffsetRow  = ReverseRow && IsColMajor ? PacketSize : 1,
+      OffsetCol  = ReverseCol && IsRowMajor ? PacketSize : 1
+    };
+    typedef internal::reverse_packet_cond<PacketType,ReversePacket> reverse_packet;
     m_argImpl.template writePacket<LoadMode>(
                                   ReverseRow ? m_rows.value() - row - OffsetRow : row,
                                   ReverseCol ? m_cols.value() - col - OffsetCol : col,
                                   reverse_packet::run(x));
   }
 
-  template<int LoadMode>
-  void writePacket(Index index, const PacketScalar& x)
+  template<int LoadMode, typename PacketType>
+  void writePacket(Index index, const PacketType& x)
   {
+    enum { PacketSize = unpacket_traits<PacketType>::size };
     m_argImpl.template writePacket<LoadMode>
       (m_rows.value() * m_cols.value() - index - PacketSize, preverse(x));
   }
diff --git a/Eigen/src/Core/DenseCoeffsBase.h b/Eigen/src/Core/DenseCoeffsBase.h
index d7ccb3b6f..81b0d6017 100644
--- a/Eigen/src/Core/DenseCoeffsBase.h
+++ b/Eigen/src/Core/DenseCoeffsBase.h
@@ -216,8 +216,9 @@ class DenseCoeffsBase<Derived,ReadOnlyAccessors> : public EigenBase<Derived>
     template<int LoadMode>
     EIGEN_STRONG_INLINE PacketReturnType packet(Index row, Index col) const
     {
+      typedef typename internal::packet_traits<Scalar>::type DefaultPacketType;
       eigen_internal_assert(row >= 0 && row < rows() && col >= 0 && col < cols());
-      return typename internal::evaluator<Derived>::type(derived()).template packet<LoadMode>(row,col);
+      return typename internal::evaluator<Derived>::type(derived()).template packet<LoadMode,DefaultPacketType>(row,col);
     }
 
 
@@ -242,8 +243,9 @@ class DenseCoeffsBase<Derived,ReadOnlyAccessors> : public EigenBase<Derived>
     template<int LoadMode>
     EIGEN_STRONG_INLINE PacketReturnType packet(Index index) const
     {
+      typedef typename internal::packet_traits<Scalar>::type DefaultPacketType;
       eigen_internal_assert(index >= 0 && index < size());
-      return typename internal::evaluator<Derived>::type(derived()).template packet<LoadMode>(index);
+      return typename internal::evaluator<Derived>::type(derived()).template packet<LoadMode,DefaultPacketType>(index);
     }
 
   protected:
diff --git a/Eigen/src/Core/Diagonal.h b/Eigen/src/Core/Diagonal.h
index c79891ae1..fa3176266 100644
--- a/Eigen/src/Core/Diagonal.h
+++ b/Eigen/src/Core/Diagonal.h
@@ -170,7 +170,7 @@ template<typename MatrixType, int _DiagIndex> class Diagonal
     EIGEN_STRONG_INLINE Index rowOffset() const { return m_index.value()>0 ? 0 : -m_index.value(); }
     EIGEN_DEVICE_FUNC
     EIGEN_STRONG_INLINE Index colOffset() const { return m_index.value()>0 ? m_index.value() : 0; }
-    // trigger a compile time error is someone try to call packet
+    // trigger a compile-time error if someone try to call packet
     template<int LoadMode> typename MatrixType::PacketReturnType packet(Index) const;
     template<int LoadMode> typename MatrixType::PacketReturnType packet(Index,Index) const;
 };
diff --git a/Eigen/src/Core/ProductEvaluators.h b/Eigen/src/Core/ProductEvaluators.h
index b24d54ef9..f2c188631 100755
--- a/Eigen/src/Core/ProductEvaluators.h
+++ b/Eigen/src/Core/ProductEvaluators.h
@@ -491,13 +491,13 @@ struct product_evaluator<Product<Lhs, Rhs, LazyProduct>, ProductTag, DenseShape,
     return (m_lhs.row(row).transpose().cwiseProduct( m_rhs.col(col) )).sum();
   }
 
-  template<int LoadMode>
-  const PacketReturnType packet(Index row, Index col) const
+  template<int LoadMode, typename PacketType>
+  const PacketType packet(Index row, Index col) const
   {
-    PacketScalar res;
+    PacketType res;
     typedef etor_product_packet_impl<Flags&RowMajorBit ? RowMajor : ColMajor,
                                      Unroll ? InnerSize : Dynamic,
-                                     LhsEtorType, RhsEtorType, PacketScalar, LoadMode> PacketImpl;
+                                     LhsEtorType, RhsEtorType, PacketType, LoadMode> PacketImpl;
 
     PacketImpl::run(row, col, m_lhsImpl, m_rhsImpl, m_innerDim, res);
     return res;
@@ -539,7 +539,7 @@ struct etor_product_packet_impl<RowMajor, UnrollingIndex, Lhs, Rhs, Packet, Load
   static EIGEN_STRONG_INLINE void run(Index row, Index col, const Lhs& lhs, const Rhs& rhs, Index innerDim, Packet &res)
   {
     etor_product_packet_impl<RowMajor, UnrollingIndex-1, Lhs, Rhs, Packet, LoadMode>::run(row, col, lhs, rhs, innerDim, res);
-    res =  pmadd(pset1<Packet>(lhs.coeff(row, UnrollingIndex-1)), rhs.template packet<LoadMode>(UnrollingIndex-1, col), res);
+    res =  pmadd(pset1<Packet>(lhs.coeff(row, UnrollingIndex-1)), rhs.template packet<LoadMode,Packet>(UnrollingIndex-1, col), res);
   }
 };
 
@@ -549,7 +549,7 @@ struct etor_product_packet_impl<ColMajor, UnrollingIndex, Lhs, Rhs, Packet, Load
   static EIGEN_STRONG_INLINE void run(Index row, Index col, const Lhs& lhs, const Rhs& rhs, Index innerDim, Packet &res)
   {
     etor_product_packet_impl<ColMajor, UnrollingIndex-1, Lhs, Rhs, Packet, LoadMode>::run(row, col, lhs, rhs, innerDim, res);
-    res =  pmadd(lhs.template packet<LoadMode>(row, UnrollingIndex-1), pset1<Packet>(rhs.coeff(UnrollingIndex-1, col)), res);
+    res =  pmadd(lhs.template packet<LoadMode,Packet>(row, UnrollingIndex-1), pset1<Packet>(rhs.coeff(UnrollingIndex-1, col)), res);
   }
 };
 
@@ -558,7 +558,7 @@ struct etor_product_packet_impl<RowMajor, 1, Lhs, Rhs, Packet, LoadMode>
 {
   static EIGEN_STRONG_INLINE void run(Index row, Index col, const Lhs& lhs, const Rhs& rhs, Index /*innerDim*/, Packet &res)
   {
-    res = pmul(pset1<Packet>(lhs.coeff(row, 0)),rhs.template packet<LoadMode>(0, col));
+    res = pmul(pset1<Packet>(lhs.coeff(row, 0)),rhs.template packet<LoadMode,Packet>(0, col));
   }
 };
 
@@ -567,7 +567,7 @@ struct etor_product_packet_impl<ColMajor, 1, Lhs, Rhs, Packet, LoadMode>
 {
   static EIGEN_STRONG_INLINE void run(Index row, Index col, const Lhs& lhs, const Rhs& rhs, Index /*innerDim*/, Packet &res)
   {
-    res = pmul(lhs.template packet<LoadMode>(row, 0), pset1<Packet>(rhs.coeff(0, col)));
+    res = pmul(lhs.template packet<LoadMode,Packet>(row, 0), pset1<Packet>(rhs.coeff(0, col)));
   }
 };
 
@@ -596,7 +596,7 @@ struct etor_product_packet_impl<RowMajor, Dynamic, Lhs, Rhs, Packet, LoadMode>
   {
     res = pset1<Packet>(0);
     for(Index i = 0; i < innerDim; ++i)
-      res =  pmadd(pset1<Packet>(lhs.coeff(row, i)), rhs.template packet<LoadMode>(i, col), res);
+      res =  pmadd(pset1<Packet>(lhs.coeff(row, i)), rhs.template packet<LoadMode,Packet>(i, col), res);
   }
 };
 
@@ -607,7 +607,7 @@ struct etor_product_packet_impl<ColMajor, Dynamic, Lhs, Rhs, Packet, LoadMode>
   {
     res = pset1<Packet>(0);
     for(Index i = 0; i < innerDim; ++i)
-      res =  pmadd(lhs.template packet<LoadMode>(row, i), pset1<Packet>(rhs.coeff(i, col)), res);
+      res =  pmadd(lhs.template packet<LoadMode,Packet>(row, i), pset1<Packet>(rhs.coeff(i, col)), res);
   }
 };
 
@@ -691,7 +691,6 @@ struct diagonal_product_evaluator_base
   : evaluator_base<Derived>
 {
    typedef typename scalar_product_traits<typename MatrixType::Scalar, typename DiagonalType::Scalar>::ReturnType Scalar;
-   typedef typename internal::packet_traits<Scalar>::type PacketScalar;
 public:
   enum {
     CoeffReadCost = NumTraits<Scalar>::MulCost + evaluator<MatrixType>::CoeffReadCost + evaluator<DiagonalType>::CoeffReadCost,
@@ -721,22 +720,22 @@ public:
   }
   
 protected:
-  template<int LoadMode>
-  EIGEN_STRONG_INLINE PacketScalar packet_impl(Index row, Index col, Index id, internal::true_type) const
+  template<int LoadMode,typename PacketType>
+  EIGEN_STRONG_INLINE PacketType packet_impl(Index row, Index col, Index id, internal::true_type) const
   {
-    return internal::pmul(m_matImpl.template packet<LoadMode>(row, col),
-                          internal::pset1<PacketScalar>(m_diagImpl.coeff(id)));
+    return internal::pmul(m_matImpl.template packet<LoadMode,PacketType>(row, col),
+                          internal::pset1<PacketType>(m_diagImpl.coeff(id)));
   }
   
-  template<int LoadMode>
-  EIGEN_STRONG_INLINE PacketScalar packet_impl(Index row, Index col, Index id, internal::false_type) const
+  template<int LoadMode,typename PacketType>
+  EIGEN_STRONG_INLINE PacketType packet_impl(Index row, Index col, Index id, internal::false_type) const
   {
     enum {
       InnerSize = (MatrixType::Flags & RowMajorBit) ? MatrixType::ColsAtCompileTime : MatrixType::RowsAtCompileTime,
       DiagonalPacketLoadMode = EIGEN_PLAIN_ENUM_MIN(LoadMode,((InnerSize%16) == 0) ? int(Aligned16) : int(evaluator<DiagonalType>::Alignment)) // FIXME hardcoded 16!!
     };
-    return internal::pmul(m_matImpl.template packet<LoadMode>(row, col),
-                          m_diagImpl.template packet<DiagonalPacketLoadMode>(id));
+    return internal::pmul(m_matImpl.template packet<LoadMode,PacketType>(row, col),
+                          m_diagImpl.template packet<DiagonalPacketLoadMode,PacketType>(id));
   }
   
   typename evaluator<DiagonalType>::nestedType m_diagImpl;
@@ -753,7 +752,6 @@ struct product_evaluator<Product<Lhs, Rhs, ProductKind>, ProductTag, DiagonalSha
   using Base::m_matImpl;
   using Base::coeff;
   typedef typename Base::Scalar Scalar;
-  typedef typename Base::PacketScalar PacketScalar;
   
   typedef Product<Lhs, Rhs, ProductKind> XprType;
   typedef typename XprType::PlainObject PlainObject;
@@ -773,19 +771,19 @@ struct product_evaluator<Product<Lhs, Rhs, ProductKind>, ProductTag, DiagonalSha
   }
   
 #ifndef __CUDACC__
-  template<int LoadMode>
-  EIGEN_STRONG_INLINE PacketScalar packet(Index row, Index col) const
+  template<int LoadMode,typename PacketType>
+  EIGEN_STRONG_INLINE PacketType packet(Index row, Index col) const
   {
     // FIXME: NVCC used to complain about the template keyword, but we have to check whether this is still the case.
     // See also similar calls below.
-    return this->template packet_impl<LoadMode>(row,col, row,
+    return this->template packet_impl<LoadMode,PacketType>(row,col, row,
                                  typename internal::conditional<int(StorageOrder)==RowMajor, internal::true_type, internal::false_type>::type());
   }
   
-  template<int LoadMode>
-  EIGEN_STRONG_INLINE PacketScalar packet(Index idx) const
+  template<int LoadMode,typename PacketType>
+  EIGEN_STRONG_INLINE PacketType packet(Index idx) const
   {
-    return packet<LoadMode>(int(StorageOrder)==ColMajor?idx:0,int(StorageOrder)==ColMajor?0:idx);
+    return packet<LoadMode,PacketType>(int(StorageOrder)==ColMajor?idx:0,int(StorageOrder)==ColMajor?0:idx);
   }
 #endif
 };
@@ -800,7 +798,6 @@ struct product_evaluator<Product<Lhs, Rhs, ProductKind>, ProductTag, DenseShape,
   using Base::m_matImpl;
   using Base::coeff;
   typedef typename Base::Scalar Scalar;
-  typedef typename Base::PacketScalar PacketScalar;
   
   typedef Product<Lhs, Rhs, ProductKind> XprType;
   typedef typename XprType::PlainObject PlainObject;
@@ -818,17 +815,17 @@ struct product_evaluator<Product<Lhs, Rhs, ProductKind>, ProductTag, DenseShape,
   }
   
 #ifndef __CUDACC__
-  template<int LoadMode>
-  EIGEN_STRONG_INLINE PacketScalar packet(Index row, Index col) const
+  template<int LoadMode,typename PacketType>
+  EIGEN_STRONG_INLINE PacketType packet(Index row, Index col) const
   {
-    return this->template packet_impl<LoadMode>(row,col, col,
+    return this->template packet_impl<LoadMode,PacketType>(row,col, col,
                                  typename internal::conditional<int(StorageOrder)==ColMajor, internal::true_type, internal::false_type>::type());
   }
   
-  template<int LoadMode>
-  EIGEN_STRONG_INLINE PacketScalar packet(Index idx) const
+  template<int LoadMode,typename PacketType>
+  EIGEN_STRONG_INLINE PacketType packet(Index idx) const
   {
-    return packet<LoadMode>(int(StorageOrder)==ColMajor?idx:0,int(StorageOrder)==ColMajor?0:idx);
+    return packet<LoadMode,PacketType>(int(StorageOrder)==ColMajor?idx:0,int(StorageOrder)==ColMajor?0:idx);
   }
 #endif
 };
diff --git a/Eigen/src/Core/Redux.h b/Eigen/src/Core/Redux.h
index 942f51d51..67ce3113e 100644
--- a/Eigen/src/Core/Redux.h
+++ b/Eigen/src/Core/Redux.h
@@ -173,7 +173,7 @@ struct redux_vec_unroller<Func, Derived, Start, 1>
 
   static EIGEN_STRONG_INLINE PacketScalar run(const Derived &mat, const Func&)
   {
-    return mat.template packetByOuterInner<alignment>(outer, inner);
+    return mat.template packetByOuterInner<alignment,PacketScalar>(outer, inner);
   }
 };
 
@@ -235,19 +235,19 @@ struct redux_impl<Func, Derived, LinearVectorizedTraversal, NoUnrolling>
     Scalar res;
     if(alignedSize)
     {
-      PacketScalar packet_res0 = mat.template packet<alignment>(alignedStart);
+      PacketScalar packet_res0 = mat.template packet<alignment,PacketScalar>(alignedStart);
       if(alignedSize>packetSize) // we have at least two packets to partly unroll the loop
       {
-        PacketScalar packet_res1 = mat.template packet<alignment>(alignedStart+packetSize);
+        PacketScalar packet_res1 = mat.template packet<alignment,PacketScalar>(alignedStart+packetSize);
         for(Index index = alignedStart + 2*packetSize; index < alignedEnd2; index += 2*packetSize)
         {
-          packet_res0 = func.packetOp(packet_res0, mat.template packet<alignment>(index));
-          packet_res1 = func.packetOp(packet_res1, mat.template packet<alignment>(index+packetSize));
+          packet_res0 = func.packetOp(packet_res0, mat.template packet<alignment,PacketScalar>(index));
+          packet_res1 = func.packetOp(packet_res1, mat.template packet<alignment,PacketScalar>(index+packetSize));
         }
 
         packet_res0 = func.packetOp(packet_res0,packet_res1);
         if(alignedEnd>alignedEnd2)
-          packet_res0 = func.packetOp(packet_res0, mat.template packet<alignment>(alignedEnd2));
+          packet_res0 = func.packetOp(packet_res0, mat.template packet<alignment,PacketScalar>(alignedEnd2));
       }
       res = func.predux(packet_res0);
 
@@ -273,7 +273,7 @@ template<typename Func, typename Derived>
 struct redux_impl<Func, Derived, SliceVectorizedTraversal, NoUnrolling>
 {
   typedef typename Derived::Scalar Scalar;
-  typedef typename packet_traits<Scalar>::type PacketScalar;
+  typedef typename packet_traits<Scalar>::type PacketType;
 
   EIGEN_DEVICE_FUNC static Scalar run(const Derived &mat, const Func& func)
   {
@@ -287,10 +287,10 @@ struct redux_impl<Func, Derived, SliceVectorizedTraversal, NoUnrolling>
     Scalar res;
     if(packetedInnerSize)
     {
-      PacketScalar packet_res = mat.template packet<Unaligned>(0,0);
+      PacketType packet_res = mat.template packet<Unaligned,PacketType>(0,0);
       for(Index j=0; j<outerSize; ++j)
         for(Index i=(j==0?packetSize:0); i<packetedInnerSize; i+=Index(packetSize))
-          packet_res = func.packetOp(packet_res, mat.template packetByOuterInner<Unaligned>(j,i));
+          packet_res = func.packetOp(packet_res, mat.template packetByOuterInner<Unaligned,PacketType>(j,i));
 
       res = func.predux(packet_res);
       for(Index j=0; j<outerSize; ++j)
@@ -371,21 +371,21 @@ public:
   CoeffReturnType coeff(Index index) const
   { return m_evaluator.coeff(index); }
 
-  template<int LoadMode>
+  template<int LoadMode, typename PacketType>
   PacketReturnType packet(Index row, Index col) const
-  { return m_evaluator.template packet<LoadMode>(row, col); }
+  { return m_evaluator.template packet<LoadMode,PacketType>(row, col); }
 
-  template<int LoadMode>
+  template<int LoadMode, typename PacketType>
   PacketReturnType packet(Index index) const
-  { return m_evaluator.template packet<LoadMode>(index); }
+  { return m_evaluator.template packet<LoadMode,PacketType>(index); }
   
   EIGEN_DEVICE_FUNC
   CoeffReturnType coeffByOuterInner(Index outer, Index inner) const
   { return m_evaluator.coeff(IsRowMajor ? outer : inner, IsRowMajor ? inner : outer); }
   
-  template<int LoadMode>
+  template<int LoadMode, typename PacketType>
   PacketReturnType packetByOuterInner(Index outer, Index inner) const
-  { return m_evaluator.template packet<LoadMode>(IsRowMajor ? outer : inner, IsRowMajor ? inner : outer); }
+  { return m_evaluator.template packet<LoadMode,PacketType>(IsRowMajor ? outer : inner, IsRowMajor ? inner : outer); }
   
   const XprType & nestedExpression() const { return m_xpr; }
   
diff --git a/Eigen/src/Core/Reverse.h b/Eigen/src/Core/Reverse.h
index 8e7f6e927..d7c380c78 100644
--- a/Eigen/src/Core/Reverse.h
+++ b/Eigen/src/Core/Reverse.h
@@ -48,14 +48,14 @@ struct traits<Reverse<MatrixType, Direction> >
   };
 };
 
-template<typename PacketScalar, bool ReversePacket> struct reverse_packet_cond
+template<typename PacketType, bool ReversePacket> struct reverse_packet_cond
 {
-  static inline PacketScalar run(const PacketScalar& x) { return preverse(x); }
+  static inline PacketType run(const PacketType& x) { return preverse(x); }
 };
 
-template<typename PacketScalar> struct reverse_packet_cond<PacketScalar,false>
+template<typename PacketType> struct reverse_packet_cond<PacketType,false>
 {
-  static inline PacketScalar run(const PacketScalar& x) { return x; }
+  static inline PacketType run(const PacketType& x) { return x; }
 };
 
 } // end namespace internal 
diff --git a/Eigen/src/Core/Swap.h b/Eigen/src/Core/Swap.h
index 3880f7b78..d70200918 100644
--- a/Eigen/src/Core/Swap.h
+++ b/Eigen/src/Core/Swap.h
@@ -21,7 +21,6 @@ class generic_dense_assignment_kernel<DstEvaluatorTypeT, SrcEvaluatorTypeT, swap
 {
 protected:
   typedef generic_dense_assignment_kernel<DstEvaluatorTypeT, SrcEvaluatorTypeT, swap_assign_op<typename DstEvaluatorTypeT::Scalar>, BuiltIn> Base;
-  typedef typename DstEvaluatorTypeT::PacketScalar PacketScalar;
   using Base::m_dst;
   using Base::m_src;
   using Base::m_functor;
@@ -35,29 +34,29 @@ public:
     : Base(dst, src, func, dstExpr)
   {}
   
-  template<int StoreMode, int LoadMode>
+  template<int StoreMode, int LoadMode, typename PacketType>
   void assignPacket(Index row, Index col)
   {
-    PacketScalar tmp = m_src.template packet<LoadMode>(row,col);
-    const_cast<SrcEvaluatorTypeT&>(m_src).template writePacket<LoadMode>(row,col, m_dst.template packet<StoreMode>(row,col));
+    PacketType tmp = m_src.template packet<LoadMode,PacketType>(row,col);
+    const_cast<SrcEvaluatorTypeT&>(m_src).template writePacket<LoadMode>(row,col, m_dst.template packet<StoreMode,PacketType>(row,col));
     m_dst.template writePacket<StoreMode>(row,col,tmp);
   }
   
-  template<int StoreMode, int LoadMode>
+  template<int StoreMode, int LoadMode, typename PacketType>
   void assignPacket(Index index)
   {
-    PacketScalar tmp = m_src.template packet<LoadMode>(index);
-    const_cast<SrcEvaluatorTypeT&>(m_src).template writePacket<LoadMode>(index, m_dst.template packet<StoreMode>(index));
+    PacketType tmp = m_src.template packet<LoadMode,PacketType>(index);
+    const_cast<SrcEvaluatorTypeT&>(m_src).template writePacket<LoadMode>(index, m_dst.template packet<StoreMode,PacketType>(index));
     m_dst.template writePacket<StoreMode>(index,tmp);
   }
   
   // TODO find a simple way not to have to copy/paste this function from generic_dense_assignment_kernel, by simple I mean no CRTP (Gael)
-  template<int StoreMode, int LoadMode>
+  template<int StoreMode, int LoadMode, typename PacketType>
   void assignPacketByOuterInner(Index outer, Index inner)
   {
     Index row = Base::rowIndexByOuterInner(outer, inner); 
     Index col = Base::colIndexByOuterInner(outer, inner);
-    assignPacket<StoreMode,LoadMode>(row, col);
+    assignPacket<StoreMode,LoadMode,PacketType>(row, col);
   }
 };
 
diff --git a/Eigen/src/Core/TriangularMatrix.h b/Eigen/src/Core/TriangularMatrix.h
index bf03ea818..351630e57 100644
--- a/Eigen/src/Core/TriangularMatrix.h
+++ b/Eigen/src/Core/TriangularMatrix.h
@@ -36,10 +36,14 @@ template<typename Derived> class TriangularBase : public EigenBase<Derived>
       MaxColsAtCompileTime = internal::traits<Derived>::MaxColsAtCompileTime,
       
       SizeAtCompileTime = (internal::size_at_compile_time<internal::traits<Derived>::RowsAtCompileTime,
-                                                   internal::traits<Derived>::ColsAtCompileTime>::ret)
-        /**< This is equal to the number of coefficients, i.e. the number of
+                                                   internal::traits<Derived>::ColsAtCompileTime>::ret),
+      /**< This is equal to the number of coefficients, i.e. the number of
           * rows times the number of columns, or to \a Dynamic if this is not
           * known at compile-time. \sa RowsAtCompileTime, ColsAtCompileTime */
+      
+      MaxSizeAtCompileTime = (internal::size_at_compile_time<internal::traits<Derived>::MaxRowsAtCompileTime,
+                                                   internal::traits<Derived>::MaxColsAtCompileTime>::ret)
+        
     };
     typedef typename internal::traits<Derived>::Scalar Scalar;
     typedef typename internal::traits<Derived>::StorageKind StorageKind;
diff --git a/Eigen/src/Core/functors/NullaryFunctors.h b/Eigen/src/Core/functors/NullaryFunctors.h
index 2362b3a7f..76a3445ce 100644
--- a/Eigen/src/Core/functors/NullaryFunctors.h
+++ b/Eigen/src/Core/functors/NullaryFunctors.h
@@ -16,13 +16,12 @@ namespace internal {
 
 template<typename Scalar>
 struct scalar_constant_op {
-  typedef typename packet_traits<Scalar>::type Packet;
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE scalar_constant_op(const scalar_constant_op& other) : m_other(other.m_other) { }
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE scalar_constant_op(const Scalar& other) : m_other(other) { }
   template<typename Index>
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Scalar operator() (Index, Index = 0) const { return m_other; }
-  template<typename Index>
-  EIGEN_STRONG_INLINE const Packet packetOp(Index, Index = 0) const { return internal::pset1<Packet>(m_other); }
+  template<typename Index, typename PacketType>
+  EIGEN_STRONG_INLINE const PacketType packetOp(Index, Index = 0) const { return internal::pset1<PacketType>(m_other); }
   const Scalar m_other;
 };
 template<typename Scalar>
@@ -39,7 +38,7 @@ template<typename Scalar>
 struct functor_traits<scalar_identity_op<Scalar> >
 { enum { Cost = NumTraits<Scalar>::AddCost, PacketAccess = false, IsRepeatable = true }; };
 
-template <typename Scalar, bool RandomAccess> struct linspaced_op_impl;
+template <typename Scalar, typename Packet, bool RandomAccess> struct linspaced_op_impl;
 
 // linear access for packet ops:
 // 1) initialization
@@ -49,11 +48,9 @@ template <typename Scalar, bool RandomAccess> struct linspaced_op_impl;
 //
 // TODO: Perhaps it's better to initialize lazily (so not in the constructor but in packetOp)
 //       in order to avoid the padd() in operator() ?
-template <typename Scalar>
-struct linspaced_op_impl<Scalar,false>
+template <typename Scalar, typename Packet>
+struct linspaced_op_impl<Scalar,Packet,false>
 {
-  typedef typename packet_traits<Scalar>::type Packet;
-
   linspaced_op_impl(const Scalar& low, const Scalar& step) :
   m_low(low), m_step(step),
   m_packetStep(pset1<Packet>(packet_traits<Scalar>::size*step)),
@@ -78,11 +75,9 @@ struct linspaced_op_impl<Scalar,false>
 // random access for packet ops:
 // 1) each step
 //   [low, ..., low] + ( [step, ..., step] * ( [i, ..., i] + [0, ..., size] ) )
-template <typename Scalar>
-struct linspaced_op_impl<Scalar,true>
+template <typename Scalar, typename Packet>
+struct linspaced_op_impl<Scalar,Packet,true>
 {
-  typedef typename packet_traits<Scalar>::type Packet;
-
   linspaced_op_impl(const Scalar& low, const Scalar& step) :
   m_low(low), m_step(step),
   m_lowPacket(pset1<Packet>(m_low)), m_stepPacket(pset1<Packet>(m_step)), m_interPacket(plset<Scalar>(0)) {}
@@ -111,7 +106,6 @@ template <typename Scalar, bool RandomAccess> struct functor_traits< linspaced_o
 { enum { Cost = 1, PacketAccess = packet_traits<Scalar>::HasSetLinear, IsRepeatable = true }; };
 template <typename Scalar, bool RandomAccess> struct linspaced_op
 {
-  typedef typename packet_traits<Scalar>::type Packet;
   linspaced_op(const Scalar& low, const Scalar& high, Index num_steps) : impl((num_steps==1 ? high : low), (num_steps==1 ? Scalar() : (high-low)/Scalar(num_steps-1))) {}
 
   template<typename Index>
@@ -126,12 +120,12 @@ template <typename Scalar, bool RandomAccess> struct linspaced_op
     return impl(col + row);
   }
 
-  template<typename Index>
+  template<typename Index, typename Packet>
   EIGEN_STRONG_INLINE const Packet packetOp(Index i) const { return impl.packetOp(i); }
 
   // We need this function when assigning e.g. a RowVectorXd to a MatrixXd since
   // there row==0 and col is used for the actual iteration.
-  template<typename Index>
+  template<typename Index, typename Packet>
   EIGEN_STRONG_INLINE const Packet packetOp(Index row, Index col) const
   {
     eigen_assert(col==0 || row==0);
@@ -141,7 +135,8 @@ template <typename Scalar, bool RandomAccess> struct linspaced_op
   // This proxy object handles the actual required temporaries, the different
   // implementations (random vs. sequential access) as well as the
   // correct piping to size 2/4 packet operations.
-  const linspaced_op_impl<Scalar,RandomAccess> impl;
+  // TODO find a way to make the packet type configurable
+  const linspaced_op_impl<Scalar,typename packet_traits<Scalar>::type,RandomAccess> impl;
 };
 
 // all functors allow linear access, except scalar_identity_op. So we fix here a quick meta