From 2b6bb9f588aa791a385c8a5075ab5e207f9a739d Mon Sep 17 00:00:00 2001
From: Rod Vagg <rod@vagg.org>
Date: Wed, 15 May 2013 21:25:11 +0200
Subject: [PATCH] deps: c-ares float, win ipv6 bad fec0 prefix

Was 72c5458aee:

  PR-URL: https://github.com/nodejs/node/pull/5090
  Reviewed-By: Fedor Indutny <fedor@indutny.com>

Reimplemented for c-ares 1.13.0

PR-URL: https://github.com/nodejs/node/pull/15378
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

PR-URL: https://github.com/nodejs/node/pull/19939
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
---
 deps/cares/src/ares_init.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/deps/cares/src/ares_init.c b/deps/cares/src/ares_init.c
index 4cc2c76dbda5ab..90cfcabdd33a9e 100644
--- a/deps/cares/src/ares_init.c
+++ b/deps/cares/src/ares_init.c
@@ -1272,6 +1272,11 @@ static int get_DNS_AdaptersAddresses(char **outptr)
       }
       else if (namesrvr.sa->sa_family == AF_INET6)
       {
+        /* Windows apparently always reports some IPv6 DNS servers that
+         * prefixed with fec0:0:0:ffff. These ususally do not point to
+         * working DNS servers, so we ignore them. */
+        if (strncmp(addresses[addressesIndex].text, "fec0:0:0:ffff:", 14) == 0)
+          continue;
         if (memcmp(&namesrvr.sa6->sin6_addr, &ares_in6addr_any,
                    sizeof(namesrvr.sa6->sin6_addr)) == 0)
           continue;