Fixed the return types of unary and binary expressions to properly handle the case where it is different from the input type (e.g. abs(complex<float>))

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

diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorEvaluator.h b/unsupported/Eigen/CXX11/src/Tensor/TensorEvaluator.h
index e324ba8..1313266 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorEvaluator.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorEvaluator.h
@@ -155,8 +155,8 @@
 
   typedef typename XprType::Index Index;
   typedef typename XprType::Scalar Scalar;
-  typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename internal::traits<XprType>::Scalar CoeffReturnType;
+  typedef typename internal::traits<XprType>::Packet PacketReturnType;
   typedef typename TensorEvaluator<ArgType, Device>::Dimensions Dimensions;
 
   EIGEN_DEVICE_FUNC const Dimensions& dimensions() const { return m_argImpl.dimensions(); }
@@ -203,8 +203,8 @@
 
   typedef typename XprType::Index Index;
   typedef typename XprType::Scalar Scalar;
-  typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename internal::traits<XprType>::Scalar CoeffReturnType;
+  typedef typename internal::traits<XprType>::Packet PacketReturnType;
   typedef typename TensorEvaluator<ArgType, Device>::Dimensions Dimensions;
 
   EIGEN_DEVICE_FUNC const Dimensions& dimensions() const { return m_argImpl.dimensions(); }
@@ -257,8 +257,8 @@
 
   typedef typename XprType::Index Index;
   typedef typename XprType::Scalar Scalar;
-  typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename internal::traits<XprType>::Scalar CoeffReturnType;
+  typedef typename internal::traits<XprType>::Packet PacketReturnType;
   typedef typename TensorEvaluator<LeftArgType, Device>::Dimensions Dimensions;
 
   EIGEN_DEVICE_FUNC const Dimensions& dimensions() const
@@ -317,8 +317,8 @@
 
   typedef typename XprType::Index Index;
   typedef typename XprType::Scalar Scalar;
-  typedef typename XprType::CoeffReturnType CoeffReturnType;
-  typedef typename XprType::PacketReturnType PacketReturnType;
+  typedef typename internal::traits<XprType>::Scalar CoeffReturnType;
+  typedef typename internal::traits<XprType>::Packet PacketReturnType;
   typedef typename TensorEvaluator<IfArgType, Device>::Dimensions Dimensions;
 
   EIGEN_DEVICE_FUNC const Dimensions& dimensions() const

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

diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorExpr.h b/unsupported/Eigen/CXX11/src/Tensor/TensorExpr.h
index de66da1..6e5503d 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorExpr.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorExpr.h
@@ -84,9 +84,7 @@
   typedef typename result_of<
                      UnaryOp(typename XprType::Scalar)
                    >::type Scalar;
-  typedef typename result_of<
-                     UnaryOp(typename XprType::Packet)
-                   >::type Packet;
+  typedef typename internal::packet_traits<Scalar>::type Packet;
   typedef typename XprType::Nested XprTypeNested;
   typedef typename remove_reference<XprTypeNested>::type _XprTypeNested;
 };
@@ -188,8 +186,7 @@
   typedef typename Eigen::NumTraits<Scalar>::Real RealScalar;
   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 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;

unsupported/test/cxx11_tensor_of_complex.cpp

diff --git a/unsupported/test/cxx11_tensor_of_complex.cpp b/unsupported/test/cxx11_tensor_of_complex.cpp
index b5044b9..24b2bcb 100644
--- a/unsupported/test/cxx11_tensor_of_complex.cpp
+++ b/unsupported/test/cxx11_tensor_of_complex.cpp
@@ -32,6 +32,22 @@
 }
 
 
+static void test_abs()
+{
+  Tensor<std::complex<float>, 1> data1(3);
+  Tensor<std::complex<double>, 1> data2(3);
+  data1.setRandom();
+  data2.setRandom();
+
+  Tensor<float, 1> abs1 = data1.abs();
+  Tensor<double, 1> abs2 = data2.abs();
+  for (int i = 0; i < 3; ++i) {
+    VERIFY_IS_APPROX(abs1(i), std::abs(data1(i)));
+    VERIFY_IS_APPROX(abs2(i), std::abs(data2(i)));
+  }
+}
+
+
 static void test_contractions()
 {
   Tensor<std::complex<float>, 4> t_left(30, 50, 8, 31);
@@ -60,5 +76,6 @@
 void test_cxx11_tensor_of_complex()
 {
   CALL_SUBTEST(test_additions());
+  CALL_SUBTEST(test_abs());
   CALL_SUBTEST(test_contractions());
 }