105 #define COLAMD_EMPTY (-1)  macro
524     Col [col].shared3.prev = COLAMD_EMPTY ;  in init_rows_cols()
525     Col [col].shared4.degree_next = COLAMD_EMPTY ;  in init_rows_cols()
873     head [c] = COLAMD_EMPTY ;  in init_scoring()
894       COLAMD_ASSERT (head [score] >= COLAMD_EMPTY) ;  in init_scoring()
898       Col [c].shared3.prev = COLAMD_EMPTY ;  in init_scoring()
903       if (next_col != COLAMD_EMPTY)  in init_scoring()
1004     COLAMD_ASSERT (head [min_score] >= COLAMD_EMPTY) ;  in find_ordering()
1007     while (min_score < n_col && head [min_score] == COLAMD_EMPTY)  in find_ordering()
1015     if (next_col != COLAMD_EMPTY)  in find_ordering()
1017       Col [next_col].shared3.prev = COLAMD_EMPTY ;  in find_ordering()
1123       pivot_row = COLAMD_EMPTY ;  in find_ordering()
1175       COLAMD_ASSERT (cur_score >= COLAMD_EMPTY) ;  in find_ordering()
1176       if (prev_col == COLAMD_EMPTY)  in find_ordering()
1184       if (next_col != COLAMD_EMPTY)  in find_ordering()
1305 	if (head_column > COLAMD_EMPTY)  in find_ordering()
1394       COLAMD_ASSERT (head [cur_score] >= COLAMD_EMPTY) ;  in find_ordering()
1397       Col [col].shared3.prev = COLAMD_EMPTY ;  in find_ordering()
1398       if (next_col != COLAMD_EMPTY)  in find_ordering()
1468     if (!COL_IS_DEAD_PRINCIPAL (i) && Col [i].shared2.order == COLAMD_EMPTY)  in order_children()
1485 	COLAMD_ASSERT (Col [c].shared2.order == COLAMD_EMPTY) ;  in order_children()
1498       } while (Col [c].shared2.order == COLAMD_EMPTY) ;  in order_children()
1593     if (head_column > COLAMD_EMPTY)  in detect_super_cols()
1604     for (super_c = first_col ; super_c != COLAMD_EMPTY ;  in detect_super_cols()
1617 	   c != COLAMD_EMPTY ; c = Col [c].shared4.hash_next)  in detect_super_cols()
1663 	Col [c].shared2.order = COLAMD_EMPTY ;  in detect_super_cols()
1671     if (head_column > COLAMD_EMPTY)  in detect_super_cols()
1674       Col [head_column].shared3.headhash = COLAMD_EMPTY ;  in detect_super_cols()
1679       head [hash] = COLAMD_EMPTY ;  in detect_super_cols()