From 3900dbc3417a2968826498f30b5efce06546d180 Mon Sep 17 00:00:00 2001
From: Gael Guennebaud <g.gael@free.fr>
Date: Tue, 27 Dec 2016 16:35:45 +0100
Subject: [PATCH] Make sure that traits<CwiseBinaryOp>::Flags reports the
 correct storage order so that methods like .outerSize()/.innerSize() work
 properly. (grafted from d32a43e33a01631745aa4c0e450153f2f3ac6b9e )

---
 Eigen/src/Core/CwiseBinaryOp.h  | 2 +-
 Eigen/src/Core/util/XprHelper.h | 9 +++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/Eigen/src/Core/CwiseBinaryOp.h b/Eigen/src/Core/CwiseBinaryOp.h
index 9ddbfe286..a36765e39 100644
--- a/Eigen/src/Core/CwiseBinaryOp.h
+++ b/Eigen/src/Core/CwiseBinaryOp.h
@@ -46,7 +46,7 @@ struct traits<CwiseBinaryOp<BinaryOp, Lhs, Rhs> >
   typedef typename remove_reference<LhsNested>::type _LhsNested;
   typedef typename remove_reference<RhsNested>::type _RhsNested;
   enum {
-    Flags = _LhsNested::Flags & RowMajorBit
+    Flags = cwise_promote_storage_order<typename traits<Lhs>::StorageKind,typename traits<Rhs>::StorageKind,_LhsNested::Flags & RowMajorBit,_RhsNested::Flags & RowMajorBit>::value
   };
 };
 } // end namespace internal
diff --git a/Eigen/src/Core/util/XprHelper.h b/Eigen/src/Core/util/XprHelper.h
index efd179b35..e88510dc7 100644
--- a/Eigen/src/Core/util/XprHelper.h
+++ b/Eigen/src/Core/util/XprHelper.h
@@ -532,6 +532,15 @@ template <typename B, typename Functor>                   struct cwise_promote_s
 template <typename Functor>                               struct cwise_promote_storage_type<Sparse,Dense,Functor>                             { typedef Sparse ret; };
 template <typename Functor>                               struct cwise_promote_storage_type<Dense,Sparse,Functor>                             { typedef Sparse ret; };
 
+template <typename LhsKind, typename RhsKind, int LhsOrder, int RhsOrder> struct cwise_promote_storage_order {
+  enum { value = LhsOrder };
+};
+
+template <typename LhsKind, int LhsOrder, int RhsOrder>   struct cwise_promote_storage_order<LhsKind,Sparse,LhsOrder,RhsOrder>                { enum { value = RhsOrder }; };
+template <typename RhsKind, int LhsOrder, int RhsOrder>   struct cwise_promote_storage_order<Sparse,RhsKind,LhsOrder,RhsOrder>                { enum { value = LhsOrder }; };
+template <int Order>                                      struct cwise_promote_storage_order<Sparse,Sparse,Order,Order>                       { enum { value = Order }; };
+
+
 /** \internal Specify the "storage kind" of multiplying an expression of kind A with kind B.
   * The template parameter ProductTag permits to specialize the resulting storage kind wrt to
   * some compile-time properties of the product: GemmProduct, GemvProduct, OuterProduct, InnerProduct.