message: Add global check for square matrix
diff: @@ -2976,8 +2976,11 @@ HypreParMatrix * HypreParMatrixFromBlocks(Array2D<HypreParMatrix*> &blocks,
  rowStarts2[0] = first_loc_row;
  rowStarts2[1] = first_loc_row + all_num_loc_rows[rank];
  - if (first_loc_row == first_loc_col &&
  - all_num_loc_rows[rank] == all_num_loc_cols[rank])
  + int square = (first_loc_row == first_loc_col &&
  + all_num_loc_rows[rank] == all_num_loc_cols[rank]);
  + MPI_Allreduce(MPI_IN_PLACE, &square, 1, MPI_INT, MPI_MAX, comm);
  +
  + if (square)
  {
  return new HypreParMatrix(comm, num_loc_rows, glob_nrows, glob_ncols,
  opI.data(), opJ.data(),
  