smpi_datatype_extent(datatype, &true_lb, &true_extent);
extent = smpi_datatype_get_extent(datatype);
smpi_datatype_extent(datatype, &true_lb, &true_extent);
extent = smpi_datatype_get_extent(datatype);
/* adjust for potential negative lower bound in datatype */
tmp_buf = (void *) ((char *) tmp_buf_free - true_lb);
/* adjust for potential negative lower bound in datatype */
tmp_buf = (void *) ((char *) tmp_buf_free - true_lb);