diff --git a/lib/cartesian/Cartesian_full.h b/lib/cartesian/Cartesian_full.h
index 88f0f699..b00d7a15 100644
--- a/lib/cartesian/Cartesian_full.h
+++ b/lib/cartesian/Cartesian_full.h
@@ -81,6 +81,8 @@ public:
       Init(dimensions,simd_layout,processor_grid);
     }
 
+    virtual ~GridCartesian() = default;
+
     void Init(const std::vector<int> &dimensions,
 	      const std::vector<int> &simd_layout,
 	      const std::vector<int> &processor_grid)
@@ -159,7 +161,6 @@ public:
       }
     };
 
-    virtual ~GridCartesian() = default;
 };
 }
 #endif
diff --git a/lib/cartesian/Cartesian_red_black.h b/lib/cartesian/Cartesian_red_black.h
index f89cacc5..166c8491 100644
--- a/lib/cartesian/Cartesian_red_black.h
+++ b/lib/cartesian/Cartesian_red_black.h
@@ -133,6 +133,8 @@ public:
     {
       Init(base->_fdimensions,base->_simd_layout,base->_processors,checker_dim_mask,checker_dim)  ;
     }
+
+    virtual ~GridRedBlackCartesian() = default;
 #if 0
     ////////////////////////////////////////////////////////////
     // Create redblack grid ;; deprecate these. Should not
diff --git a/lib/communicator/Communicator_mpi.cc b/lib/communicator/Communicator_mpi.cc
index 678e4517..5a2dc4d0 100644
--- a/lib/communicator/Communicator_mpi.cc
+++ b/lib/communicator/Communicator_mpi.cc
@@ -52,6 +52,13 @@ void CartesianCommunicator::Init(int *argc, char ***argv) {
   MPI_Comm_dup (MPI_COMM_WORLD,&communicator_world);
   ShmInitGeneric();
 }
+
+CartesianCommunicator::~CartesianCommunicator()
+{
+  if (communicator && !MPI::Is_finalized())
+    MPI_Comm_free(&communicator);
+}
+
 void CartesianCommunicator::GlobalSum(uint32_t &u){
   int ierr=MPI_Allreduce(MPI_IN_PLACE,&u,1,MPI_UINT32_T,MPI_SUM,communicator);
   assert(ierr==0);
diff --git a/lib/communicator/Communicator_mpit.cc b/lib/communicator/Communicator_mpit.cc
index 5137c27b..15ee13fd 100644
--- a/lib/communicator/Communicator_mpit.cc
+++ b/lib/communicator/Communicator_mpit.cc
@@ -53,6 +53,13 @@ void CartesianCommunicator::Init(int *argc, char ***argv) {
   ShmInitGeneric();
 }
 
+CartesianCommunicator::~CartesianCommunicator()
+{
+  if (communicator && !MPI::Is_finalized())
+    MPI_Comm_free(&communicator);
+}
+
+
 void CartesianCommunicator::GlobalSum(uint32_t &u){
   int ierr=MPI_Allreduce(MPI_IN_PLACE,&u,1,MPI_UINT32_T,MPI_SUM,communicator);
   assert(ierr==0);
diff --git a/lib/communicator/Communicator_none.cc b/lib/communicator/Communicator_none.cc
index d9d875b7..629a3e4a 100644
--- a/lib/communicator/Communicator_none.cc
+++ b/lib/communicator/Communicator_none.cc
@@ -57,8 +57,7 @@ CartesianCommunicator::CartesianCommunicator(const std::vector<int> &processors)
 }
 
 CartesianCommunicator::~CartesianCommunicator(){}
-  
-  
+
 void CartesianCommunicator::GlobalSum(float &){}
 void CartesianCommunicator::GlobalSumVector(float *,int N){}
 void CartesianCommunicator::GlobalSum(double &){}
diff --git a/tests/hmc/Test_hmc_ScalarActionNxN.cc b/tests/hmc/Test_hmc_ScalarActionNxN.cc
index a4dad1a3..9e40beac 100644
--- a/tests/hmc/Test_hmc_ScalarActionNxN.cc
+++ b/tests/hmc/Test_hmc_ScalarActionNxN.cc
@@ -31,7 +31,8 @@ class ScalarActionParameters : Serializable {
  public:
   GRID_SERIALIZABLE_CLASS_MEMBERS(ScalarActionParameters,
     double, mass_squared,
-    double, lambda);
+    double, lambda,
+    double, g);
 
     template <class ReaderClass >
   ScalarActionParameters(Reader<ReaderClass>& Reader){
@@ -140,7 +141,7 @@ int main(int argc, char **argv) {
 
   // Scalar action in adjoint representation
   ScalarActionParameters SPar(Reader);
-  ScalarAction Saction(SPar.mass_squared, SPar.lambda);
+  ScalarAction Saction(SPar.mass_squared, SPar.lambda, SPar.g);
 
   // Collect actions
   ActionLevel<ScalarAction::Field, ScalarNxNMatrixFields<Ncolours>> Level1(1);