- const struct ovsdb_idl_table_class *class = row->table->class;
- size_t column_idx = column - class->columns;
+ const struct ovsdb_idl_table_class *class;
+ size_t column_idx;
+
+ assert(!ovsdb_idl_row_is_synthetic(row));
+
+ class = row->table->class;
+ column_idx = column - class->columns;