if (not is_contig || not is_homogeneous) {
if (rank != root) {
position = 0;
mpi_errno = MPI_Unpack(tmp_buf, nbytes, &position, buffer, count, datatype, comm);
if (not is_contig || not is_homogeneous) {
if (rank != root) {
position = 0;
mpi_errno = MPI_Unpack(tmp_buf, nbytes, &position, buffer, count, datatype, comm);