diff --git a/src/3rdParty/salomesmesh/src/SMDS/SMDS_UnstructuredGrid.cpp b/src/3rdParty/salomesmesh/src/SMDS/SMDS_UnstructuredGrid.cpp
index ce9b01a4d2..f5b91ff800 100644
--- a/src/3rdParty/salomesmesh/src/SMDS/SMDS_UnstructuredGrid.cpp
+++ b/src/3rdParty/salomesmesh/src/SMDS/SMDS_UnstructuredGrid.cpp
@@ -193,8 +193,8 @@ void SMDS_UnstructuredGrid::compactGrid(std::vector<int>& idNodesOldToNew, int n
 
   vtkCellArray *newConnectivity = vtkCellArray::New();
   newConnectivity->Initialize();
-  int oldCellDataSize = this->Connectivity->GetData()->GetSize();
-  newConnectivity->Allocate(oldCellDataSize);
+  int oldCellDataSize = this->GetCells()->GetConnectivityArray()->GetSize();
+  newConnectivity->AllocateExact(oldCellDataSize, oldCellDataSize);
   MESSAGE("oldCellSize="<< oldCellSize << " oldCellDataSize=" << oldCellDataSize);
 
   vtkUnsignedCharArray *newTypes = vtkUnsignedCharArray::New();
@@ -420,7 +420,8 @@ void SMDS_UnstructuredGrid::copyBloc(vtkUnsignedCharArray *newTypes,
           //MESSAGE("   " << oldval << " " << pointsCell[l]);
         }
       /*int newcnt = */newConnectivity->InsertNextCell(nbpts, pointsCell);
-      int newLoc = newConnectivity->GetInsertLocation(nbpts);
+      int newLoc = this->GetCells()->GetOffsetsArray()->GetNumberOfValues() - 1
+        + this->GetCells()->GetConnectivityArray()->GetNumberOfValues() - nbpts - 1;
       //MESSAGE(newcnt << " " << newLoc);
       newLocations->SetValue(alreadyCopied, newLoc);
       alreadyCopied++;