Fix rule-of-3 for the Tensor module.

Adds copy constructors to Tensor ops, inherits assignment operators from
`TensorBase`.

Addresses #1863

1 files changed, 13 insertions, 0 deletions

diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorBase.h b/unsupported/Eigen/CXX11/src/Tensor/TensorBase.h
index 3a70d8517..679996c02 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorBase.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorBase.h
@@ -966,6 +966,7 @@ class TensorBase<Derived, ReadOnlyAccessors>
 template<typename Derived, int AccessLevel = internal::accessors_level<Derived>::value>
 class TensorBase : public TensorBase<Derived, ReadOnlyAccessors> {
  public:
+    typedef TensorBase<Derived, ReadOnlyAccessors> Base;
     typedef internal::traits<Derived> DerivedTraits;
     typedef typename DerivedTraits::Scalar Scalar;
     typedef typename DerivedTraits::Index Index;
@@ -1146,6 +1147,18 @@ class TensorBase : public TensorBase<Derived, ReadOnlyAccessors> {
     }
 
  protected:
+    EIGEN_DEFAULT_EMPTY_CONSTRUCTOR_AND_DESTRUCTOR(TensorBase)
+    EIGEN_DEFAULT_COPY_CONSTRUCTOR(TensorBase)
+
+    template<typename OtherDerived> EIGEN_DEVICE_FUNC
+    EIGEN_STRONG_INLINE Derived& operator=(const OtherDerived& other)
+    {
+      typedef TensorAssignOp<Derived, const OtherDerived> Assign;
+      Assign assign(derived(), other.derived());
+      internal::TensorExecutor<const Assign, DefaultDevice>::run(assign, DefaultDevice());
+      return derived();
+    }
+
     EIGEN_DEVICE_FUNC
     EIGEN_STRONG_INLINE Derived& derived() { return *static_cast<Derived*>(this); }
     EIGEN_DEVICE_FUNC