From 8d16e2aa27681bc9cc6e3ecaf700353adc40b97d Mon Sep 17 00:00:00 2001
From: Gael Guennebaud <g.gael@free.fr>
Date: Wed, 13 Apr 2016 18:40:02 +0200
Subject: [PATCH] Fix detection of same matrices for expressions not handled by
 extract_data

---
 Eigen/src/Core/PermutationMatrix.h          | 3 ++-
 Eigen/src/Core/SolveTriangular.h            | 3 ++-
 Eigen/src/Core/Transpositions.h             | 3 ++-
 Eigen/src/Householder/HouseholderSequence.h | 3 ++-
 Eigen/src/LU/Inverse.h                      | 2 +-
 5 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/Eigen/src/Core/PermutationMatrix.h b/Eigen/src/Core/PermutationMatrix.h
index 85ffae265..bda79fa04 100644
--- a/Eigen/src/Core/PermutationMatrix.h
+++ b/Eigen/src/Core/PermutationMatrix.h
@@ -584,10 +584,11 @@ struct permut_matrix_product_retval
       const Index n = Side==OnTheLeft ? rows() : cols();
       // FIXME we need an is_same for expression that is not sensitive to constness. For instance
       // is_same_xpr<Block<const Matrix>, Block<Matrix> >::value should be true.
+      const typename Dest::Scalar *dst_data = internal::extract_data(dst);
       if(    is_same<MatrixTypeNestedCleaned,Dest>::value
           && blas_traits<MatrixTypeNestedCleaned>::HasUsableDirectAccess
           && blas_traits<Dest>::HasUsableDirectAccess
-          && extract_data(dst) == extract_data(m_matrix))
+          && dst_data!=0 && dst_data == extract_data(m_matrix))
       {
         // apply the permutation inplace
         Matrix<bool,PermutationType::RowsAtCompileTime,1,0,PermutationType::MaxRowsAtCompileTime> mask(m_permutation.size());
diff --git a/Eigen/src/Core/SolveTriangular.h b/Eigen/src/Core/SolveTriangular.h
index 83565ddd8..30c9c38ec 100644
--- a/Eigen/src/Core/SolveTriangular.h
+++ b/Eigen/src/Core/SolveTriangular.h
@@ -243,7 +243,8 @@ template<int Side, typename TriangularType, typename Rhs> struct triangular_solv
 
   template<typename Dest> inline void evalTo(Dest& dst) const
   {
-    if(!(is_same<RhsNestedCleaned,Dest>::value && extract_data(dst) == extract_data(m_rhs)))
+    const typename Dest::Scalar *dst_data = internal::extract_data(dst);
+    if(!(is_same<RhsNestedCleaned,Dest>::value && dst_data!=0 && extract_data(dst) == extract_data(m_rhs)))
       dst = m_rhs;
     m_triangularMatrix.template solveInPlace<Side>(dst);
   }
diff --git a/Eigen/src/Core/Transpositions.h b/Eigen/src/Core/Transpositions.h
index e4ba0756f..16bc1ce15 100644
--- a/Eigen/src/Core/Transpositions.h
+++ b/Eigen/src/Core/Transpositions.h
@@ -376,7 +376,8 @@ struct transposition_matrix_product_retval
       const int size = m_transpositions.size();
       Index j = 0;
 
-      if(!(is_same<MatrixTypeNestedCleaned,Dest>::value && extract_data(dst) == extract_data(m_matrix)))
+      const typename Dest::Scalar *dst_data = internal::extract_data(dst);
+      if(!(is_same<MatrixTypeNestedCleaned,Dest>::value && dst_data!=0 && dst_data == extract_data(m_matrix)))
         dst = m_matrix;
 
       for(int k=(Transposed?size-1:0) ; Transposed?k>=0:k<size ; Transposed?--k:++k)
diff --git a/Eigen/src/Householder/HouseholderSequence.h b/Eigen/src/Householder/HouseholderSequence.h
index d800ca1fa..aea2439a9 100644
--- a/Eigen/src/Householder/HouseholderSequence.h
+++ b/Eigen/src/Householder/HouseholderSequence.h
@@ -237,8 +237,9 @@ template<typename VectorsType, typename CoeffsType, int Side> class HouseholderS
     {
       workspace.resize(rows());
       Index vecs = m_length;
+      const typename Dest::Scalar *dst_data = internal::extract_data(dst);
       if(    internal::is_same<typename internal::remove_all<VectorsType>::type,Dest>::value
-          && internal::extract_data(dst) == internal::extract_data(m_vectors))
+          && dst_data!=0 && dst_data == internal::extract_data(m_vectors))
       {
         // in-place
         dst.diagonal().setOnes();
diff --git a/Eigen/src/LU/Inverse.h b/Eigen/src/LU/Inverse.h
index 3cf887193..e836fd696 100644
--- a/Eigen/src/LU/Inverse.h
+++ b/Eigen/src/LU/Inverse.h
@@ -290,7 +290,7 @@ struct inverse_impl : public ReturnByValue<inverse_impl<MatrixType> >
   {
     const int Size = EIGEN_PLAIN_ENUM_MIN(MatrixType::ColsAtCompileTime,Dest::ColsAtCompileTime);
     EIGEN_ONLY_USED_FOR_DEBUG(Size);
-    eigen_assert(( (Size<=1) || (Size>4) || (extract_data(m_matrix)!=extract_data(dst)))
+    eigen_assert(( (Size<=1) || (Size>4) || (extract_data(m_matrix)!=0 && extract_data(m_matrix)!=extract_data(dst)))
               && "Aliasing problem detected in inverse(), you need to do inverse().eval() here.");
 
     compute_inverse<MatrixTypeNestedCleaned, Dest>::run(m_matrix, dst);