Don't use AI_V4MAPPED.

runtime/bin/socket_linux.cc

Index: runtime/bin/socket_linux.cc
diff --git a/runtime/bin/socket_linux.cc b/runtime/bin/socket_linux.cc
index eec3c609f2e9e9dbd31b8be22f564011e4060d07..aaff4d9378c7274362dcccf46880851f4160e8b9 100644
--- a/runtime/bin/socket_linux.cc
+++ b/runtime/bin/socket_linux.cc
@@ -212,14 +212,14 @@ AddressList<SocketAddress>* Socket::LookupAddress(const char* host,
   memset(&hints, 0, sizeof(hints));
   hints.ai_family = SocketAddress::FromType(type);
   hints.ai_socktype = SOCK_STREAM;
-  hints.ai_flags = (AI_V4MAPPED | AI_ADDRCONFIG);
+  hints.ai_flags = AI_ADDRCONFIG;
   hints.ai_protocol = IPPROTO_TCP;
   struct addrinfo* info = NULL;
   int status = NO_RETRY_EXPECTED(getaddrinfo(host, 0, &hints, &info));
   if (status != 0) {
     // We failed, try without AI_ADDRCONFIG. This can happen when looking up
     // e.g. '::1', when there are no global IPv6 addresses.
-    hints.ai_flags = AI_V4MAPPED;
+    hints.ai_flags = 0;
     status = NO_RETRY_EXPECTED(getaddrinfo(host, 0, &hints, &info));
     if (status != 0) {
       ASSERT(*os_error == NULL);