+typedef int item_number_t;
+# define ITEM_NUMBER_MAX ((item_number_t) INT_MAX)
+# define ITEM_NUMBER_MIN ((item_number_t) INT_MIN)
+extern item_number_t *ritem;
+extern unsigned int nritems;
+
+/* There is weird relationship between OT1H item_number_t and OTOH
+ symbol_number_t and rule_number_t: we store the latter in
+ item_number_t. symbol_number_t are stored as are, while
+ the negation of (rule_number_t + 1) are stored.
+
+ Therefore, an symbol_number_t must be a valid item_number_t, and we
+ sometimes have to perform the converse transformation. */
+# define symbol_number_as_item_number(Tok) ((item_number_t) (Tok))
+# define item_number_as_symbol_number(Ite) ((symbol_number_t) (Ite))
+
+extern symbol_number_t start_symbol;