smpi_datatype_create(new_type, count * blocklen * smpi_datatype_size(old_type), 0, ((count -1) * stride + blocklen)*
smpi_datatype_size(old_type), 0, nullptr, DT_FLAG_VECTOR|DT_FLAG_CONTIGUOUS);
retval=MPI_SUCCESS;
smpi_datatype_create(new_type, count * blocklen * smpi_datatype_size(old_type), 0, ((count -1) * stride + blocklen)*
smpi_datatype_size(old_type), 0, nullptr, DT_FLAG_VECTOR|DT_FLAG_CONTIGUOUS);
retval=MPI_SUCCESS;