From 94f2cfc9c7646e2f6b946db3c3b6078a2635f025 Mon Sep 17 00:00:00 2001
From: Gael Guennebaud <g.gael@free.fr>
Date: Fri, 18 Nov 2016 10:09:33 +0100
Subject: [PATCH] bug #1343: fix compilation regression in array =
 matrix_product (grafted from cebff7e3a22d3fde9f83f11fc44a4e8166e6cc2d )

---
 Eigen/src/Core/GeneralProduct.h |  2 +-
 test/product_extra.cpp          | 10 ++++++++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/Eigen/src/Core/GeneralProduct.h b/Eigen/src/Core/GeneralProduct.h
index a8c83f168..0cc2d08e2 100644
--- a/Eigen/src/Core/GeneralProduct.h
+++ b/Eigen/src/Core/GeneralProduct.h
@@ -264,7 +264,7 @@ template<> struct gemv_dense_selector<OnTheRight,ColMajor,true>
     if (!evalToDest)
     {
       if(!alphaIsCompatible)
-        dest += actualAlpha * MappedDest(actualDestPtr, dest.size());
+        dest.matrix() += actualAlpha * MappedDest(actualDestPtr, dest.size());
       else
         dest = MappedDest(actualDestPtr, dest.size());
     }
diff --git a/test/product_extra.cpp b/test/product_extra.cpp
index 03d5c3657..e2b855bff 100644
--- a/test/product_extra.cpp
+++ b/test/product_extra.cpp
@@ -98,6 +98,16 @@ template<typename MatrixType> void product_extra(const MatrixType& m)
   // regression test
   MatrixType tmp = m1 * m1.adjoint() * s1;
   VERIFY_IS_APPROX(tmp, m1 * m1.adjoint() * s1);
+
+  // regression test for bug 1343, assignment to arrays
+  Array<Scalar,Dynamic,1> a1 = m1 * vc2;
+  VERIFY_IS_APPROX(a1.matrix(),m1*vc2);
+  Array<Scalar,Dynamic,1> a2 = s1 * (m1 * vc2);
+  VERIFY_IS_APPROX(a2.matrix(),s1*m1*vc2);
+  Array<Scalar,1,Dynamic> a3 = v1 * m1;
+  VERIFY_IS_APPROX(a3.matrix(),v1*m1);
+  Array<Scalar,Dynamic,Dynamic> a4 = m1 * m2.adjoint();
+  VERIFY_IS_APPROX(a4.matrix(),m1*m2.adjoint());
 }
 
 // Regression test for bug reported at http://forum.kde.org/viewtopic.php?f=74&t=96947