extern int dns_lookup(dns_answer *, const uschar *, int, const uschar **);
extern void dns_pattern_init(void);
extern int dns_special_lookup(dns_answer *, const uschar *, int, const uschar **);
-extern dns_record *dns_next_rr(dns_answer *, dns_scan *, int);
+extern dns_record *dns_next_rr(const dns_answer *, dns_scan *, int);
extern uschar *dns_text_type(int);
extern void dscp_list_to_stream(FILE *);
extern BOOL dscp_lookup(const uschar *, int, int *, int *, int *);
driver_info *, int, void *, int, optionlist *, int);
extern uschar *readconf_find_option(void *);
extern void readconf_main(BOOL);
-extern void readconf_options_from_list(optionlist *, unsigned, uschar *);
+extern void readconf_options_from_list(optionlist *, unsigned, const uschar *, uschar *);
extern void readconf_options_routers(void);
extern void readconf_options_transports(void);
extern void readconf_print(uschar *, uschar *, BOOL);