Fix configure to enable warnings and fix most of them.

lib/event.c

@@ -49,7 +49,8 @@ static struct resclass ev_class = {
   "Event",
   sizeof(event),
   (void (*)(resource *)) ev_postpone,
-  ev_dump
+  ev_dump,
+  NULL
 };
 
 /**

lib/ip.h

@@ -46,7 +46,7 @@ char *ip_scope_text(unsigned);
 
 struct prefix {
   ip_addr addr;
-  int len;
+  unsigned int len;
 };
 
 #define ip_is_prefix(a,l) (!ipa_nonzero(ipa_and(a, ipa_not(ipa_mkmask(l)))))

lib/ipv4.h

@@ -72,7 +72,7 @@ int ipv4_classify(u32);
 u32 ipv4_class_mask(u32);
 byte *ipv4_skip_header(byte *, int *);
 
-static inline int ipv4_has_link_scope(u32 a)
+static inline int ipv4_has_link_scope(u32 a UNUSED)
 {
   return 0;
 }

lib/socket.h

@@ -66,6 +66,8 @@ int sk_leave_group(sock *s, ip_addr maddr);
 int sk_set_ipv6_checksum(sock *s, int offset);
 #endif
 
+int sk_set_broadcast(sock *s, int enable);
+
 static inline int
 sk_send_buffer_empty(sock *sk)
 {