message: Fix memory leak in HypreParMatrix::Threshold
diff: @@ -1295,11 +1295,17 @@ void HypreParMatrix::Threshold(double threshold)
  ierr += hypre_CSRMatrixDestroy(csr_A_wo_z);
  - ierr += hypre_ParCSRMatrixDestroy(A);
  -
  MFEM_VERIFY(ierr == 0, "");
  + Destroy();
  + Init();
  +
  A = parcsr_A_ptr;
  +
  + hypre_ParCSRMatrixSetNumNonzeros(A);
  + hypre_MatvecCommPkgCreate(A);
  + height = GetNumRows();
  + width = GetNumCols();
  }
  void HypreParMatrix::EliminateRowsCols(const Array<int> &rows_cols,
  