extern uschar *parse_extract_address(const uschar *, uschar **, int *, int *, int *,
BOOL);
-extern int parse_forward_list(uschar *, int, address_item **, uschar **,
+extern int parse_forward_list(const uschar *, int, address_item **, uschar **,
const uschar *, uschar *, error_block **);
-extern uschar *parse_find_address_end(uschar *, BOOL);
+extern uschar *parse_find_address_end(const uschar *, BOOL);
extern const uschar *parse_find_at(const uschar *);
extern const uschar *parse_fix_phrase(const uschar *, int);
extern const uschar *parse_message_id(const uschar *, uschar **, uschar **);