diff --git a/Eigen/Sparse b/Eigen/Sparse
index 2364c6fe4..54b15b8ae 100644
--- a/Eigen/Sparse
+++ b/Eigen/Sparse
@@ -8,6 +8,10 @@
 #include <cstring>
 #include <algorithm>
 
+#ifdef EIGEN_GOOGLEHASH_SUPPORT
+  #include <google/dense_hash_map>
+#endif
+
 #ifdef EIGEN_CHOLMOD_SUPPORT
   extern "C" {
     #include "cholmod.h"
@@ -70,10 +74,10 @@ namespace Eigen {
 #include "src/Sparse/RandomSetter.h"
 #include "src/Sparse/SparseBlock.h"
 #include "src/Sparse/SparseMatrix.h"
-#include "src/Sparse/HashMatrix.h"
-#include "src/Sparse/LinkedVectorMatrix.h"
+//#include "src/Sparse/HashMatrix.h"
+//#include "src/Sparse/LinkedVectorMatrix.h"
 #include "src/Sparse/CoreIterators.h"
-#include "src/Sparse/SparseSetter.h"
+//#include "src/Sparse/SparseSetter.h"
 #include "src/Sparse/SparseProduct.h"
 #include "src/Sparse/TriangularSolver.h"
 #include "src/Sparse/SparseLLT.h"
diff --git a/Eigen/src/Sparse/RandomSetter.h b/Eigen/src/Sparse/RandomSetter.h
index 8606e03c6..35bc9daee 100644
--- a/Eigen/src/Sparse/RandomSetter.h
+++ b/Eigen/src/Sparse/RandomSetter.h
@@ -29,6 +29,9 @@ template<typename Scalar> struct StdMapTraits
 {
   typedef int KeyType;
   typedef std::map<KeyType,Scalar> Type;
+  enum {
+    IsSorted = 1
+  };
 
   static void setInvalidKey(Type&, const KeyType&) {}
 };
@@ -38,6 +41,9 @@ template<typename Scalar> struct GnuHashMapTraits
 {
   typedef int KeyType;
   typedef __gnu_cxx::hash_map<KeyType,Scalar> Type;
+  enum {
+    IsSorted = 0
+  };
 
   static void setInvalidKey(Type&, const KeyType&) {}
 };
@@ -48,6 +54,9 @@ template<typename Scalar> struct GoogleDenseHashMapTraits
 {
   typedef int KeyType;
   typedef google::dense_hash_map<KeyType,Scalar> Type;
+  enum {
+    IsSorted = 0
+  };
 
   static void setInvalidKey(Type& map, const KeyType& k)
   { map.set_empty_key(k); }
@@ -59,6 +68,9 @@ template<typename Scalar> struct GoogleSparseHashMapTraits
 {
   typedef int KeyType;
   typedef google::sparse_hash_map<KeyType,Scalar> Type;
+  enum {
+    IsSorted = 0
+  };
 
   static void setInvalidKey(Type&, const KeyType&) {}
 };
@@ -66,10 +78,35 @@ template<typename Scalar> struct GoogleSparseHashMapTraits
 
 /** \class RandomSetter
   *
+  * Typical usage:
+  * \code
+  * SparseMatrix<double> m(rows,cols);
+  * {
+  *   RandomSetter<SparseMatrix<double> > w(m);
+  *   // don't use m but w instead with read/write random access to the coefficients:
+  *   for(;;)
+  *     w(rand(),rand()) = rand;
+  * }
+  * // when w is deleted, the data are copied back to m
+  * // and m is ready to use.
+  * \endcode
+  *
+  * \note for performance and memory consumption reasons it is highly recommended to use
+  * Google's hash library. To do so you have two options:
+  *  - include <google/dense_hash_map> yourself \b before Eigen/Sparse header
+  *  - define EIGEN_GOOGLEHASH_SUPPORT
+  * In the later case the inclusion of <google/dense_hash_map> is made for you.
   */
 template<typename SparseMatrixType,
-         template <typename T> class HashMapTraits = StdMapTraits,
-         int OuterPacketBits = 6>
+         template <typename T> class MapTraits =
+#if defined _DENSE_HASH_MAP_H_
+          GoogleDenseHashMapTraits
+#elif defined _HASH_MAP
+          GnuHashMapTraits
+#else
+          StdMapTraits
+#endif
+         ,int OuterPacketBits = 6>
 class RandomSetter
 {
     typedef typename ei_traits<SparseMatrixType>::Scalar Scalar;
@@ -78,11 +115,13 @@ class RandomSetter
       ScalarWrapper() : value(0) {}
       Scalar value;
     };
-    typedef typename HashMapTraits<ScalarWrapper>::KeyType KeyType;
-    typedef typename HashMapTraits<ScalarWrapper>::Type HashMapType;
+    typedef typename MapTraits<ScalarWrapper>::KeyType KeyType;
+    typedef typename MapTraits<ScalarWrapper>::Type HashMapType;
     static const int OuterPacketMask = (1 << OuterPacketBits) - 1;
     enum {
-      RowMajor = SparseMatrixType::Flags & RowMajorBit
+      SwapStorage = 1 - MapTraits<ScalarWrapper>::IsSorted,
+      TargetRowMajor = (SparseMatrixType::Flags & RowMajorBit) ? 1 : 0,
+      SetterRowMajor = SwapStorage ? 1-TargetRowMajor : TargetRowMajor
     };
 
   public:
@@ -90,31 +129,114 @@ class RandomSetter
     inline RandomSetter(SparseMatrixType& target)
       : mp_target(&target)
     {
-      m_outerPackets = target.outerSize() >> OuterPacketBits;
-      if (target.outerSize()&OuterPacketMask)
+      const int outerSize = SwapStorage ? target.innerSize() : target.outerSize();
+      const int innerSize = SwapStorage ? target.outerSize() : target.innerSize();
+      m_outerPackets = outerSize >> OuterPacketBits;
+      if (outerSize&OuterPacketMask)
         m_outerPackets += 1;
       m_hashmaps = new HashMapType[m_outerPackets];
-      KeyType ik = (1<<OuterPacketBits)*mp_target->innerSize()+1;
+      // compute number of bits needed to store inner indices
+      int aux = innerSize - 1;
+      m_keyBitsOffset = 0;
+      while (aux)
+      {
+        m_keyBitsOffset++;
+        aux = aux >> 1;
+      }
+      KeyType ik = (1<<(OuterPacketBits+m_keyBitsOffset));
       for (int k=0; k<m_outerPackets; ++k)
-        HashMapTraits<ScalarWrapper>::setInvalidKey(m_hashmaps[k],ik);
+        MapTraits<ScalarWrapper>::setInvalidKey(m_hashmaps[k],ik);
+
+      // insert current coeffs
+      for (int j=0; j<mp_target->outerSize(); ++j)
+        for (typename SparseMatrixType::InnerIterator it(*mp_target,j); it; ++it)
+          (*this)(TargetRowMajor?j:it.index(), TargetRowMajor?it.index():j) = it.value();
     }
 
     ~RandomSetter()
     {
+      KeyType keyBitsMask = (1<<m_keyBitsOffset)-1;
+      if (!SwapStorage) // also means the map is sorted
+      {
+        mp_target->startFill(nonZeros());
+        for (int k=0; k<m_outerPackets; ++k)
+        {
+          const int outerOffset = (1<<OuterPacketBits) * k;
+          typename HashMapType::iterator end = m_hashmaps[k].end();
+          for (typename HashMapType::iterator it = m_hashmaps[k].begin(); it!=end; ++it)
+          {
+            const int outer = (it->first >> m_keyBitsOffset) + outerOffset;
+            const int inner = it->first & keyBitsMask;
+            mp_target->fill(TargetRowMajor ? outer : inner, TargetRowMajor ? inner : outer) = it->second.value;
+          }
+        }
+        mp_target->endFill();
+      }
+      else
+      {
+        VectorXi positions(mp_target->outerSize());
+        positions.setZero();
+        // pass 1
+        for (int k=0; k<m_outerPackets; ++k)
+        {
+          typename HashMapType::iterator end = m_hashmaps[k].end();
+          for (typename HashMapType::iterator it = m_hashmaps[k].begin(); it!=end; ++it)
+          {
+            const int outer = it->first & keyBitsMask;
+            positions[outer]++;
+          }
+        }
+        // prefix sum
+        int count = 0;
+        for (int j=0; j<mp_target->outerSize(); ++j)
+        {
+          int tmp = positions[j];
+          mp_target->_outerIndexPtr()[j] = count;
+          positions[j] = count;
+          count += tmp;
+        }
+        mp_target->_outerIndexPtr()[mp_target->outerSize()] = count;
+        mp_target->resizeNonZeros(count);
+        // pass 2
+        for (int k=0; k<m_outerPackets; ++k)
+        {
+          const int outerOffset = (1<<OuterPacketBits) * k;
+          typename HashMapType::iterator end = m_hashmaps[k].end();
+          for (typename HashMapType::iterator it = m_hashmaps[k].begin(); it!=end; ++it)
+          {
+            const int inner = (it->first >> m_keyBitsOffset) + outerOffset;
+            const int outer = it->first & keyBitsMask;
+            // sorted insertion
+            // Note that we have to deal with at most 2^OuterPacketBits unsorted coefficients,
+            // moreover those 2^OuterPacketBits coeffs are likely to be sparse, an so only a
+            // small fraction of them have to be sorted, whence the following simple procedure:
+            int posStart = mp_target->_outerIndexPtr()[outer];
+            int i = (positions[outer]++) - 1;
+            while ( (i >= posStart) && (mp_target->_innerIndexPtr()[i] > inner) )
+            {
+              mp_target->_valuePtr()[i+1] = mp_target->_valuePtr()[i];
+              mp_target->_innerIndexPtr()[i+1] = mp_target->_innerIndexPtr()[i];
+              --i;
+            }
+            mp_target->_innerIndexPtr()[i+1] = inner;
+            mp_target->_valuePtr()[i+1] = it->second.value;
+          }
+        }
+      }
       delete[] m_hashmaps;
     }
 
     Scalar& operator() (int row, int col)
     {
-      const int outer = RowMajor ? row : col;
-      const int inner = RowMajor ? col : row;
-      const int outerMajor = outer >> OuterPacketBits;
-      const int outerMinor = outer & OuterPacketMask;
-      const KeyType key = inner + outerMinor * mp_target->innerSize();
-
+      const int outer = SetterRowMajor ? row : col;
+      const int inner = SetterRowMajor ? col : row;
+      const int outerMajor = outer >> OuterPacketBits; // index of the packet/map
+      const int outerMinor = outer & OuterPacketMask;  // index of the inner vector in the packet
+      const KeyType key = (KeyType(outerMinor)<<m_keyBitsOffset) | inner;
       return m_hashmaps[outerMajor][key].value;
     }
 
+    // might be slow
     int nonZeros() const
     {
       int nz = 0;
@@ -129,6 +251,7 @@ class RandomSetter
     HashMapType* m_hashmaps;
     SparseMatrixType* mp_target;
     int m_outerPackets;
+    unsigned char m_keyBitsOffset;
 };
 
 #endif // EIGEN_RANDOMSETTER_H
diff --git a/Eigen/src/Sparse/SparseMatrixBase.h b/Eigen/src/Sparse/SparseMatrixBase.h
index b03fb5cee..2695f23b1 100644
--- a/Eigen/src/Sparse/SparseMatrixBase.h
+++ b/Eigen/src/Sparse/SparseMatrixBase.h
@@ -64,10 +64,11 @@ class SparseMatrixBase : public MatrixBase<Derived>
     {
 //       std::cout << "Derived& operator=(const MatrixBase<OtherDerived>& other)\n";
       const bool transpose = (Flags & RowMajorBit) != (OtherDerived::Flags & RowMajorBit);
-//       std::cout << "eval transpose = " << transpose << "\n";
+      ei_assert((!transpose) && "the transpose operation is supposed to be handled in SparseMatrix::operator=");
       const int outerSize = other.outerSize();
-      typedef typename ei_meta_if<transpose, LinkedVectorMatrix<Scalar,Flags&RowMajorBit>, Derived>::ret TempType;
-      TempType temp(other.rows(), other.cols());
+      //typedef typename ei_meta_if<transpose, LinkedVectorMatrix<Scalar,Flags&RowMajorBit>, Derived>::ret TempType;
+      // thanks to shallow copies, we always eval to a tempary
+      Derived temp(other.rows(), other.cols());
 
       temp.startFill(std::max(this->rows(),this->cols())*2);
       for (int j=0; j<outerSize; ++j)
diff --git a/bench/sparse_cholesky.cpp b/bench/sparse_cholesky.cpp
index d1d29c152..0a17848a0 100644
--- a/bench/sparse_cholesky.cpp
+++ b/bench/sparse_cholesky.cpp
@@ -1,5 +1,5 @@
-#define EIGEN_TAUCS_SUPPORT
-#define EIGEN_CHOLMOD_SUPPORT
+// #define EIGEN_TAUCS_SUPPORT
+// #define EIGEN_CHOLMOD_SUPPORT
 #include <Eigen/Sparse>
 
 // g++ -DSIZE=10000 -DDENSITY=0.001  sparse_cholesky.cpp -I.. -DDENSEMATRI -O3 -g0 -DNDEBUG   -DNBTRIES=1 -I /home/gael/Coding/LinearAlgebra/taucs_full/src/ -I/home/gael/Coding/LinearAlgebra/taucs_full/build/linux/  -L/home/gael/Coding/LinearAlgebra/taucs_full/lib/linux/ -ltaucs /home/gael/Coding/LinearAlgebra/GotoBLAS/libgoto.a -lpthread -I /home/gael/Coding/LinearAlgebra/SuiteSparse/CHOLMOD/Include/ $CHOLLIB -I /home/gael/Coding/LinearAlgebra/SuiteSparse/UFconfig/ /home/gael/Coding/LinearAlgebra/SuiteSparse/CCOLAMD/Lib/libccolamd.a   /home/gael/Coding/LinearAlgebra/SuiteSparse/CHOLMOD/Lib/libcholmod.a -lmetis /home/gael/Coding/LinearAlgebra/SuiteSparse/AMD/Lib/libamd.a  /home/gael/Coding/LinearAlgebra/SuiteSparse/CAMD/Lib/libcamd.a   /home/gael/Coding/LinearAlgebra/SuiteSparse/CCOLAMD/Lib/libccolamd.a  /home/gael/Coding/LinearAlgebra/SuiteSparse/COLAMD/Lib/libcolamd.a -llapack && ./a.out
@@ -70,7 +70,7 @@ void doEigen(const char* name, const EigenSparseSelfAdjointMatrix& sm1, int flag
   std::cout << ":\t" << timer.value() << endl;
 
   std::cout << "  nnz: " << sm1.nonZeros() << " => " << chol.matrixL().nonZeros() << "\n";
-  //std::cout << "sparse\n" << chol.matrixL() << "%\n";
+  std::cout << "sparse\n" << chol.matrixL() << "%\n";
 }
 
 int main(int argc, char *argv[])
diff --git a/bench/sparse_randomsetter.cpp b/bench/sparse_randomsetter.cpp
index 7868e177a..61753d8c2 100644
--- a/bench/sparse_randomsetter.cpp
+++ b/bench/sparse_randomsetter.cpp
@@ -37,6 +37,31 @@
         X  \
   } timer.stop(); }
 
+
+static double rtime;
+static double nentries;
+
+template<typename SetterType>
+void dostuff(const char* name, EigenSparseMatrix& sm1)
+{
+  int rows = sm1.rows();
+  int cols = sm1.cols();
+  sm1.setZero();
+  BenchTimer t;
+  SetterType* set1 = new SetterType(sm1);
+  t.reset(); t.start();
+  for (int k=0; k<nentries; ++k)
+    (*set1)(ei_random<int>(0,rows-1),ei_random<int>(0,cols-1)) += 1;
+  t.stop();
+  std::cout << "std::map =>      \t" << t.value()-rtime
+            << " nnz=" << set1->nonZeros() << std::flush;
+
+  // getchar();
+
+  t.reset(); t.start(); delete set1; t.stop();
+  std::cout << "  back: \t" << t.value() << "\n";
+}
+    
 int main(int argc, char *argv[])
 {
   int rows = SIZE;
@@ -46,56 +71,52 @@ int main(int argc, char *argv[])
   EigenSparseMatrix sm1(rows,cols), sm2(rows,cols);
 
 
-  int n = rows*cols*density;
-  std::cout << "n = " << n << "\n";
+  nentries = rows*cols*density;
+  std::cout << "n = " << nentries << "\n";
   int dummy;
   BenchTimer t;
 
   t.reset(); t.start();
-  for (int k=0; k<n; ++k)
+  for (int k=0; k<nentries; ++k)
     dummy = ei_random<int>(0,rows-1) + ei_random<int>(0,cols-1);
   t.stop();
-  double rtime = t.value();
+  rtime = t.value();
   std::cout << "rtime = " << rtime << " (" << dummy << ")\n\n";
   const int Bits = 6;
   for (;;)
   {
-    {
-      RandomSetter<EigenSparseMatrix,StdMapTraits,Bits> set1(sm1);
-      t.reset(); t.start();
-      for (int k=0; k<n; ++k)
-        set1(ei_random<int>(0,rows-1),ei_random<int>(0,cols-1)) += 1;
-      t.stop();
-      std::cout << "std::map =>      \t" << t.value()-rtime
-                << " nnz=" << set1.nonZeros() << "\n";getchar();
-    }
-    {
-      RandomSetter<EigenSparseMatrix,GnuHashMapTraits,Bits> set1(sm1);
-      t.reset(); t.start();
-      for (int k=0; k<n; ++k)
-        set1(ei_random<int>(0,rows-1),ei_random<int>(0,cols-1)) += 1;
-      t.stop();
-      std::cout << "gnu::hash_map => \t" << t.value()-rtime
-                << " nnz=" << set1.nonZeros() << "\n";getchar();
-    }
-    {
-      RandomSetter<EigenSparseMatrix,GoogleDenseHashMapTraits,Bits> set1(sm1);
-      t.reset(); t.start();
-      for (int k=0; k<n; ++k)
-        set1(ei_random<int>(0,rows-1),ei_random<int>(0,cols-1)) += 1;
-      t.stop();
-      std::cout << "google::dense => \t" << t.value()-rtime
-                << " nnz=" << set1.nonZeros() << "\n";getchar();
-    }
-    {
-      RandomSetter<EigenSparseMatrix,GoogleSparseHashMapTraits,Bits> set1(sm1);
-      t.reset(); t.start();
-      for (int k=0; k<n; ++k)
-        set1(ei_random<int>(0,rows-1),ei_random<int>(0,cols-1)) += 1;
-      t.stop();
-      std::cout << "google::sparse => \t" << t.value()-rtime
-                << " nnz=" << set1.nonZeros() << "\n";getchar();
-    }
+    dostuff<RandomSetter<EigenSparseMatrix,StdMapTraits,Bits> >("std::map     ", sm1);
+    dostuff<RandomSetter<EigenSparseMatrix,GnuHashMapTraits,Bits> >("gnu::hash_map", sm1);
+    dostuff<RandomSetter<EigenSparseMatrix,GoogleDenseHashMapTraits,Bits> >("google::dense", sm1);
+    dostuff<RandomSetter<EigenSparseMatrix,GoogleSparseHashMapTraits,Bits> >("google::sparse", sm1);
+
+//     {
+//       RandomSetter<EigenSparseMatrix,GnuHashMapTraits,Bits> set1(sm1);
+//       t.reset(); t.start();
+//       for (int k=0; k<n; ++k)
+//         set1(ei_random<int>(0,rows-1),ei_random<int>(0,cols-1)) += 1;
+//       t.stop();
+//       std::cout << "gnu::hash_map => \t" << t.value()-rtime
+//                 << " nnz=" << set1.nonZeros() << "\n";getchar();
+//     }
+//     {
+//       RandomSetter<EigenSparseMatrix,GoogleDenseHashMapTraits,Bits> set1(sm1);
+//       t.reset(); t.start();
+//       for (int k=0; k<n; ++k)
+//         set1(ei_random<int>(0,rows-1),ei_random<int>(0,cols-1)) += 1;
+//       t.stop();
+//       std::cout << "google::dense => \t" << t.value()-rtime
+//                 << " nnz=" << set1.nonZeros() << "\n";getchar();
+//     }
+//     {
+//       RandomSetter<EigenSparseMatrix,GoogleSparseHashMapTraits,Bits> set1(sm1);
+//       t.reset(); t.start();
+//       for (int k=0; k<n; ++k)
+//         set1(ei_random<int>(0,rows-1),ei_random<int>(0,cols-1)) += 1;
+//       t.stop();
+//       std::cout << "google::sparse => \t" << t.value()-rtime
+//                 << " nnz=" << set1.nonZeros() << "\n";getchar();
+//     }
     std::cout << "\n\n";
   }
 
diff --git a/cmake/FindCholmod.cmake b/cmake/FindCholmod.cmake
index 794c14fb5..444279ab9 100644
--- a/cmake/FindCholmod.cmake
+++ b/cmake/FindCholmod.cmake
@@ -22,9 +22,7 @@ if(CHOLMOD_LIBRARIES)
   find_library(AMD_LIBRARY amd PATHS ${CHOLMOD_LIBDIR} $ENV{CHOLMODDIR} ${LIB_INSTALL_DIR})
   if (AMD_LIBRARY)
     set(CHOLMOD_LIBRARIES ${CHOLMOD_LIBRARIES} ${AMD_LIBRARY})
-    message ("AMD_LIBRARY found")
   else (AMD_LIBRARY)
-    message ("AMD_LIBRARY not found")
     set(CHOLMOD_LIBRARIES FALSE)
   endif (AMD_LIBRARY)
 
diff --git a/cmake/FindGoogleHash.cmake b/cmake/FindGoogleHash.cmake
new file mode 100644
index 000000000..767996b41
--- /dev/null
+++ b/cmake/FindGoogleHash.cmake
@@ -0,0 +1,16 @@
+
+if (GOOGLEHASH_INCLUDES AND GOOGLEHASH_LIBRARIES)
+  set(GOOGLEHASH_FIND_QUIETLY TRUE)
+endif (GOOGLEHASH_INCLUDES AND GOOGLEHASH_LIBRARIES)
+
+find_path(GOOGLEHASH_INCLUDES
+  NAMES
+  google/dense_hash_map
+  PATHS
+  ${INCLUDE_INSTALL_DIR}
+)
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(GOOGLEHASH DEFAULT_MSG GOOGLEHASH_INCLUDES)
+
+mark_as_advanced(GOOGLEHASH_INCLUDES)
diff --git a/Eigen/src/Sparse/HashMatrix.h b/disabled/HashMatrix.h
similarity index 100%
rename from Eigen/src/Sparse/HashMatrix.h
rename to disabled/HashMatrix.h
diff --git a/Eigen/src/Sparse/LinkedVectorMatrix.h b/disabled/LinkedVectorMatrix.h
similarity index 100%
rename from Eigen/src/Sparse/LinkedVectorMatrix.h
rename to disabled/LinkedVectorMatrix.h
diff --git a/Eigen/src/Sparse/SparseSetter.h b/disabled/SparseSetter.h
similarity index 100%
rename from Eigen/src/Sparse/SparseSetter.h
rename to disabled/SparseSetter.h
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 1320e9b53..39729fe7e 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -13,14 +13,17 @@ if(TAUCS_FOUND)
   add_definitions("-DEIGEN_TAUCS_SUPPORT")
   include_directories(${TAUCS_INCLUDES})
   set(EXTERNAL_LIBS ${EXTERNAL_LIBS} ${TAUCS_LIBRARIES})
+else(TAUCS_FOUND)
+  message("TAUCS not found, this optional backend won't be tested")
 endif(TAUCS_FOUND)
 
 find_package(Cholmod)
 if(CHOLMOD_FOUND)
-  message("add EIGEN_CHOLMOD_SUPPORT " ${CHOLMOD_LIBRARIES})
   add_definitions("-DEIGEN_CHOLMOD_SUPPORT")
   include_directories(${CHOLMOD_INCLUDES})
   set(EXTERNAL_LIBS ${EXTERNAL_LIBS} ${CHOLMOD_LIBRARIES})
+else(CHOLMOD_FOUND)
+  message("CHOLMOD not found, this optional backend won't be tested")
 endif(CHOLMOD_FOUND)
 
 find_package(Umfpack)
@@ -28,6 +31,8 @@ if(UMFPACK_FOUND)
   add_definitions("-DEIGEN_UMFPACK_SUPPORT")
   include_directories(${UMFPACK_INCLUDES})
   set(EXTERNAL_LIBS ${EXTERNAL_LIBS} ${UMFPACK_LIBRARIES})
+else(UMFPACK_FOUND)
+  message("UMFPACK not found, this optional backend won't be tested")
 endif(UMFPACK_FOUND)
 
 find_package(SuperLU)
@@ -35,8 +40,18 @@ if(SUPERLU_FOUND)
   add_definitions("-DEIGEN_SUPERLU_SUPPORT")
   include_directories(${SUPERLU_INCLUDES})
   set(EXTERNAL_LIBS ${EXTERNAL_LIBS} ${SUPERLU_LIBRARIES})
+else(SUPERLU_FOUND)
+  message("SUPERLU not found, this optional backend won't be tested")
 endif(SUPERLU_FOUND)
 
+find_package(GoogleHash)
+if(GOOGLEHASH_FOUND)
+  add_definitions("-DEIGEN_GOOGLEHASH_SUPPORT")
+  include_directories(${GOOGLEHASH_INCLUDES})
+else(GOOGLEHASH_FOUND)
+  message("Google's hash library not found, those map implementations won't be tested")
+endif(GOOGLEHASH_FOUND)
+
 if(CMAKE_COMPILER_IS_GNUCXX)
   if(CMAKE_SYSTEM_NAME MATCHES Linux)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -g2")
@@ -152,6 +167,6 @@ ei_add_test(geometry)
 ei_add_test(hyperplane)
 ei_add_test(parametrizedline)
 ei_add_test(regression)
-ei_add_test(sparse ${EI_OFLAG})
+ei_add_test(sparse )
 
 endif(BUILD_TESTS)
diff --git a/test/sparse.cpp b/test/sparse.cpp
index 6470b1bbf..949aed940 100644
--- a/test/sparse.cpp
+++ b/test/sparse.cpp
@@ -22,6 +22,14 @@
 // License and a copy of the GNU General Public License along with
 // Eigen. If not, see <http://www.gnu.org/licenses/>.
 
+#ifdef __GNUC__
+#include <ext/hash_map>
+#endif
+
+#ifdef EIGEN_GOOGLEHASH_SUPPORT
+  #include <google/sparse_hash_map>
+#endif
+
 #include "main.h"
 #include <Eigen/Cholesky>
 #include <Eigen/LU>
@@ -72,6 +80,24 @@ initSparse(double density,
   sparseMat.endFill();
 }
 
+template<typename SetterType,typename DenseType, typename SparseType>
+bool test_random_setter(SparseType& sm, const DenseType& ref, const std::vector<Vector2i>& nonzeroCoords)
+{
+  {
+    sm.setZero();
+    SetterType w(sm);
+    std::vector<Vector2i> remaining = nonzeroCoords;
+    while(!remaining.empty())
+    {
+      int i = ei_random<int>(0,remaining.size()-1);
+      w(remaining[i].x(),remaining[i].y()) = ref.coeff(remaining[i].x(),remaining[i].y());
+      remaining[i] = remaining.back();
+      remaining.pop_back();
+    }
+  }
+  return sm.isApprox(ref);
+}
+
 template<typename Scalar> void sparse(int rows, int cols)
 {
   double density = std::max(8./(rows*cols), 0.01);
@@ -157,20 +183,48 @@ template<typename Scalar> void sparse(int rows, int cols)
 //   VERIFY_IS_APPROX(m, refMat);
 
   // random setter
-  {
-    m.setZero();
-    VERIFY_IS_NOT_APPROX(m, refMat);
-    SparseSetter<SparseMatrix<Scalar>, RandomAccessPattern> w(m);
-    std::vector<Vector2i> remaining = nonzeroCoords;
-    while(!remaining.empty())
-    {
-      int i = ei_random<int>(0,remaining.size()-1);
-      w->coeffRef(remaining[i].x(),remaining[i].y()) = refMat.coeff(remaining[i].x(),remaining[i].y());
-      remaining[i] = remaining.back();
-      remaining.pop_back();
-    }
-  }
-  VERIFY_IS_APPROX(m, refMat);
+//   {
+//     m.setZero();
+//     VERIFY_IS_NOT_APPROX(m, refMat);
+//     SparseSetter<SparseMatrix<Scalar>, RandomAccessPattern> w(m);
+//     std::vector<Vector2i> remaining = nonzeroCoords;
+//     while(!remaining.empty())
+//     {
+//       int i = ei_random<int>(0,remaining.size()-1);
+//       w->coeffRef(remaining[i].x(),remaining[i].y()) = refMat.coeff(remaining[i].x(),remaining[i].y());
+//       remaining[i] = remaining.back();
+//       remaining.pop_back();
+//     }
+//   }
+//   VERIFY_IS_APPROX(m, refMat);
+
+    VERIFY(( test_random_setter<RandomSetter<SparseMatrix<Scalar>, StdMapTraits> >(m,refMat,nonzeroCoords) ));
+    #ifdef _HASH_MAP
+    VERIFY(( test_random_setter<RandomSetter<SparseMatrix<Scalar>, GnuHashMapTraits> >(m,refMat,nonzeroCoords) ));
+    #endif
+    #ifdef _DENSE_HASH_MAP_H_
+    VERIFY(( test_random_setter<RandomSetter<SparseMatrix<Scalar>, GoogleDenseHashMapTraits> >(m,refMat,nonzeroCoords) ));
+    #endif
+    #ifdef _SPARSE_HASH_MAP_H_
+    VERIFY(( test_random_setter<RandomSetter<SparseMatrix<Scalar>, GoogleSparseHashMapTraits> >(m,refMat,nonzeroCoords) ));
+    #endif
+//   {
+//     m.setZero();
+//     VERIFY_IS_NOT_APPROX(m, refMat);
+// //     RandomSetter<SparseMatrix<Scalar> > w(m);
+//     RandomSetter<SparseMatrix<Scalar>, GoogleDenseHashMapTraits > w(m);
+//     // RandomSetter<SparseMatrix<Scalar>, GnuHashMapTraits > w(m);
+//     std::vector<Vector2i> remaining = nonzeroCoords;
+//     while(!remaining.empty())
+//     {
+//       int i = ei_random<int>(0,remaining.size()-1);
+//       w(remaining[i].x(),remaining[i].y()) = refMat.coeff(remaining[i].x(),remaining[i].y());
+//       remaining[i] = remaining.back();
+//       remaining.pop_back();
+//     }
+//   }
+//   std::cerr << m.transpose() << "\n\n"  << refMat.transpose() << "\n\n";
+//   VERIFY_IS_APPROX(m, refMat);
 
   // test transpose
   {
@@ -180,7 +234,7 @@ template<typename Scalar> void sparse(int rows, int cols)
     VERIFY_IS_APPROX(m2.transpose().eval(), refMat2.transpose().eval());
     VERIFY_IS_APPROX(m2.transpose(), refMat2.transpose());
   }
-
+#if 0
   // test matrix product
   {
     DenseMatrix refMat2 = DenseMatrix::Zero(rows, rows);
@@ -306,7 +360,7 @@ template<typename Scalar> void sparse(int rows, int cols)
     #endif
     count++;
   }
-
+#endif
 }
 
 void test_sparse()