resolve: really suppport IPv6 only networks on iOS/OS X

[zeeker999]

Further fix for PR #886
Fixes #883

[jay]

This changes the behavior, you will have to guard that area with ipv6,

diff --git a/lib/asyn-thread.c b/lib/asyn-thread.c
index 0ca2603..0504fb0 100644
--- a/lib/asyn-thread.c
+++ b/lib/asyn-thread.c
@@ -608,45 +608,47 @@ Curl_addrinfo *Curl_resolver_getaddrinfo(struct connectdat
 #ifndef USE_RESOLVE_ON_IPS
   /* First check if this is an IPv4 address string */
   if(Curl_inet_pton(AF_INET, hostname, &in) > 0)
     /* This is a dotted IP address 123.123.123.123-style */
     return Curl_ip2addr(AF_INET, &in, hostname, port);

 #ifdef CURLRES_IPV6
   /* check if this is an IPv6 address string */
   if(Curl_inet_pton(AF_INET6, hostname, &in6) > 0)
     /* This is an IPv6 address literal */
     return Curl_ip2addr(AF_INET6, &in6, hostname, port);

+#endif /* CURLRES_IPV6 */
+#endif /* !USE_RESOLVE_ON_IPS */
+
+#ifdef CURLRES_IPV6
   /*
    * Check if a limited name resolve has been requested.
    */
   switch(conn->ip_version) {
   case CURL_IPRESOLVE_V4:
     pf = PF_INET;
     break;
   case CURL_IPRESOLVE_V6:
     pf = PF_INET6;
     break;
   default:
     pf = PF_UNSPEC;
     break;
   }

   if((pf != PF_INET) && !Curl_ipv6works())
     /* The stack seems to be a non-IPv6 one */
     pf = PF_INET;
-
 #endif /* CURLRES_IPV6 */
-#endif /* USE_RESOLVE_ON_IPS */

   memset(&hints, 0, sizeof(hints));
   hints.ai_family = pf;
   hints.ai_socktype = conn->socktype;

   snprintf(sbuf, sizeof(sbuf), "%d", port);

   /* fire up a new resolver thread! */
   if(init_resolve_thread(conn, hostname, port, &hints)) {
     *waitp = 1; /* expect asynchronous response */
     return NULL;
   }

[zeeker999]

This changes the behavior, you will have to guard that area with ipv6,

Fixed, and squashed to previous commit as 97fe665.

[jay]

Thanks, landed in 608d161.