From 7a5f83ca60c667898e6d8096dac5680793ddfce9 Mon Sep 17 00:00:00 2001
From: Gael Guennebaud <g.gael@free.fr>
Date: Thu, 29 Oct 2015 03:55:39 -0700
Subject: [PATCH] Add overloads for real times sparse<complex> operations. This
 avoids real to complex conversions, and also fixes a compilation issue with
 MSVC.

---
 Eigen/src/Core/ArrayBase.h              |  4 +---
 Eigen/src/Core/DenseBase.h              | 15 ++++++---------
 Eigen/src/Core/util/XprHelper.h         |  8 ++++----
 Eigen/src/SparseCore/SparseMatrixBase.h | 16 ++++++++++++++--
 4 files changed, 25 insertions(+), 18 deletions(-)

diff --git a/Eigen/src/Core/ArrayBase.h b/Eigen/src/Core/ArrayBase.h
index 151c05526..66813c8ea 100644
--- a/Eigen/src/Core/ArrayBase.h
+++ b/Eigen/src/Core/ArrayBase.h
@@ -46,15 +46,13 @@ template<typename Derived> class ArrayBase
 
     typedef ArrayBase Eigen_BaseClassForSpecializationOfGlobalMathFuncImpl;
 
-    using internal::special_scalar_op_base<Derived,typename internal::traits<Derived>::Scalar,
-                typename NumTraits<typename internal::traits<Derived>::Scalar>::Real>::operator*;
-
     typedef typename internal::traits<Derived>::StorageKind StorageKind;
     typedef typename internal::traits<Derived>::Scalar Scalar;
     typedef typename internal::packet_traits<Scalar>::type PacketScalar;
     typedef typename NumTraits<Scalar>::Real RealScalar;
 
     typedef DenseBase<Derived> Base;
+    using Base::operator*;
     using Base::RowsAtCompileTime;
     using Base::ColsAtCompileTime;
     using Base::SizeAtCompileTime;
diff --git a/Eigen/src/Core/DenseBase.h b/Eigen/src/Core/DenseBase.h
index 488f15061..e181dafaf 100644
--- a/Eigen/src/Core/DenseBase.h
+++ b/Eigen/src/Core/DenseBase.h
@@ -40,18 +40,14 @@ static inline void check_DenseIndex_is_signed() {
   */
 template<typename Derived> class DenseBase
 #ifndef EIGEN_PARSED_BY_DOXYGEN
-  : public internal::special_scalar_op_base<Derived,typename internal::traits<Derived>::Scalar,
-                                     typename NumTraits<typename internal::traits<Derived>::Scalar>::Real>
+  : public internal::special_scalar_op_base<Derived, typename internal::traits<Derived>::Scalar,
+                                            typename NumTraits<typename internal::traits<Derived>::Scalar>::Real,
+                                            DenseCoeffsBase<Derived> >
 #else
   : public DenseCoeffsBase<Derived>
 #endif // not EIGEN_PARSED_BY_DOXYGEN
 {
   public:
-    using internal::special_scalar_op_base<Derived,typename internal::traits<Derived>::Scalar,
-                typename NumTraits<typename internal::traits<Derived>::Scalar>::Real>::operator*;
-    using internal::special_scalar_op_base<Derived,typename internal::traits<Derived>::Scalar,
-                typename NumTraits<typename internal::traits<Derived>::Scalar>::Real>::operator/;
-
 
     /** Inner iterator type to iterate over the coefficients of a row or column.
       * \sa class InnerIterator
@@ -77,9 +73,10 @@ template<typename Derived> class DenseBase
     typedef Scalar value_type;
     
     typedef typename NumTraits<Scalar>::Real RealScalar;
+    typedef internal::special_scalar_op_base<Derived,Scalar,RealScalar, DenseCoeffsBase<Derived> > Base;
 
-    typedef internal::special_scalar_op_base<Derived,typename internal::traits<Derived>::Scalar,
-                      typename NumTraits<typename internal::traits<Derived>::Scalar>::Real> Base;
+    using Base::operator*;
+    using Base::operator/;
     using Base::derived;
     using Base::const_cast_derived;
     using Base::rows;
diff --git a/Eigen/src/Core/util/XprHelper.h b/Eigen/src/Core/util/XprHelper.h
index 209c73e1e..f9e2959cc 100644
--- a/Eigen/src/Core/util/XprHelper.h
+++ b/Eigen/src/Core/util/XprHelper.h
@@ -452,9 +452,9 @@ struct generic_xpr_base<Derived, XprKind, Dense>
 
 /** \internal Helper base class to add a scalar multiple operator
   * overloads for complex types */
-template<typename Derived,typename Scalar,typename OtherScalar,
+template<typename Derived, typename Scalar, typename OtherScalar, typename BaseType,
          bool EnableIt = !is_same<Scalar,OtherScalar>::value >
-struct special_scalar_op_base : public DenseCoeffsBase<Derived>
+struct special_scalar_op_base : public BaseType
 {
   // dummy operator* so that the
   // "using special_scalar_op_base::operator*" compiles
@@ -463,8 +463,8 @@ struct special_scalar_op_base : public DenseCoeffsBase<Derived>
   void operator/(dummy) const;
 };
 
-template<typename Derived,typename Scalar,typename OtherScalar>
-struct special_scalar_op_base<Derived,Scalar,OtherScalar,true>  : public DenseCoeffsBase<Derived>
+template<typename Derived,typename Scalar,typename OtherScalar, typename BaseType>
+struct special_scalar_op_base<Derived,Scalar,OtherScalar,BaseType,true>  : public BaseType
 {
   const CwiseUnaryOp<scalar_multiple2_op<Scalar,OtherScalar>, Derived>
   operator*(const OtherScalar& scalar) const
diff --git a/Eigen/src/SparseCore/SparseMatrixBase.h b/Eigen/src/SparseCore/SparseMatrixBase.h
index 38eb1c37a..74b498a47 100644
--- a/Eigen/src/SparseCore/SparseMatrixBase.h
+++ b/Eigen/src/SparseCore/SparseMatrixBase.h
@@ -23,7 +23,14 @@ namespace Eigen {
   * This class can be extended with the help of the plugin mechanism described on the page
   * \ref TopicCustomizingEigen by defining the preprocessor symbol \c EIGEN_SPARSEMATRIXBASE_PLUGIN.
   */
-template<typename Derived> class SparseMatrixBase : public EigenBase<Derived>
+template<typename Derived> class SparseMatrixBase
+#ifndef EIGEN_PARSED_BY_DOXYGEN
+  : public internal::special_scalar_op_base<Derived,typename internal::traits<Derived>::Scalar,
+                                            typename NumTraits<typename internal::traits<Derived>::Scalar>::Real,
+                                            EigenBase<Derived> >
+#else
+  : public EigenBase<Derived>
+#endif // not EIGEN_PARSED_BY_DOXYGEN
 {
   public:
 
@@ -42,7 +49,12 @@ template<typename Derived> class SparseMatrixBase : public EigenBase<Derived>
                      >::type PacketReturnType;
 
     typedef SparseMatrixBase StorageBaseType;
-    typedef EigenBase<Derived> Base;
+    typedef typename NumTraits<Scalar>::Real RealScalar;
+    typedef internal::special_scalar_op_base<Derived, Scalar, RealScalar, EigenBase<Derived> > Base;
+
+    using Base::operator*;
+    using Base::operator/;
+
     typedef Matrix<StorageIndex,Dynamic,1> IndexVector;
     typedef Matrix<Scalar,Dynamic,1> ScalarVector;