Don't use AI_V4MAPPED.

runtime/bin/socket_linux.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "platform/globals.h"
 #if defined(TARGET_OS_LINUX)
 
 #include <errno.h>  // NOLINT
 #include <stdio.h>  // NOLINT
 #include <stdlib.h>  // NOLINT
@@ skipping 194 matching lines @@
 
 
 AddressList<SocketAddress>* Socket::LookupAddress(const char* host,
                                                   int type,
                                                   OSError** os_error) {
   // Perform a name lookup for a host name.
   struct addrinfo hints;
   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);
       *os_error = new OSError(status,
                               gai_strerror(status),
                               OSError::kGetAddressInfo);
       return NULL;
     }
   }
   intptr_t count = 0;
@@ skipping 327 matching lines @@
   mreq.gr_interface = interfaceIndex;
   memmove(&mreq.gr_group, &addr->ss, SocketAddress::GetAddrLength(addr));
   return NO_RETRY_EXPECTED(
       setsockopt(fd, proto, MCAST_LEAVE_GROUP, &mreq, sizeof(mreq))) == 0;
 }
 
 }  // namespace bin
 }  // namespace dart
 
 #endif  // defined(TARGET_OS_LINUX)