[deal.II] trilinos sparsity pattern: end iterator of last locally owned row triggers trilinos error

[Simon]

Dear all,

attached is a minimal example with 125 dofs, where dofs with indices 0-74 
live on proccesor 0 and dofs with indices 75-124 live on processor 1
(two MPI processes).

Consider the following code to loop over the rows of a Trilinos sparsity 
pattern:
// make_sparsity_pattern,...
for(unsigned int row = 0; row < dofHandler.n_dofs(); ++row)
{
   if( ! sparsityPattern.row_is_stored_locally(row)) continue;
   auto it = sparsityPattern.begin(row); 
   auto itend = sparsityPattern.end(row); 
   // do something with the columns
   while(it != itend) { it->column();...}
}

For row=74 on processor 0, there is an error 

dealii::TrilinosWrappers::SparsityPatternIterators::Accessor::visit_present_row()
"An error with error number -1 occurred while calling a Trilinos function"

The mentioned Trilinos function is ExtractGlobalRowCopy() and the error 
number
suggests an access to a row which is not locally owned. 
This makes sense to me because 
sparsityPattern.end(74) calls visit_present_row(75),
which is indeed not locally owned.

Not sure whether I miss something or this is a bug.
My expectation was to use the begin and end iterators on all locally owned 
rows.

Thank you,
Simon

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#include <deal.II/lac/trilinos_vector.h>
#include <deal.II/lac/affine_constraints.h>
#include <deal.II/lac/trilinos_sparsity_pattern.h>
#include <deal.II/lac/trilinos_sparse_matrix.h>
#include <deal.II/dofs/dof_renumbering.h>
#include <deal.II/dofs/dof_tools.h>

#include <deal.II/base/index_set.h>
#include <deal.II/base/utilities.h>

#include <deal.II/dofs/dof_handler.h>

#include <deal.II/distributed/grid_refinement.h>
#include <deal.II/distributed/tria.h>
#include <deal.II/grid/grid_generator.h>

#include <deal.II/fe/fe_q.h>

#include <iostream>

namespace dealiiLA
{
  using namespace dealii::TrilinosWrappers;
} 

int main(int argc, char *argv[])
{
    dealii::Utilities::MPI::MPI_InitFinalize mpiInitialization(argc, argv, 1);
    MPI_Comm const &mpiCommunicator(MPI_COMM_WORLD);
    
    dealii::parallel::distributed::Triangulation<3> tria(mpiCommunicator);
    dealii::GridGenerator::hyper_cube(tria);
    tria.refine_global(2);
    
    dealii::DoFHandler<3> dofHandler(tria);
    dealii::FE_Q<3> fe(1);
    dofHandler.distribute_dofs(fe);

    dealii::DoFRenumbering::component_wise(dofHandler);

    dealii::IndexSet locallyOwnedDofs = dofHandler.locally_owned_dofs();

    dealiiLA::SparsityPattern sparsityPattern;
    sparsityPattern.reinit(locallyOwnedDofs, mpiCommunicator);
    dealii::DoFTools::make_sparsity_pattern(dofHandler,
                                              sparsityPattern,
                                              dealii::AffineConstraints(),
                                              false,
                                              
dealii::Utilities::MPI::this_mpi_process(
                                                mpiCommunicator));
    sparsityPattern.compress();

    for(unsigned int i=0; i<dofHandler.n_dofs(); ++i)
    {
      if(!sparsityPattern.row_is_stored_locally(i))
        continue;
        
      auto it = sparsityPattern.begin(i);
      auto itend = sparsityPattern.end(i);
    }

  return 0;
}