commit c6a67c92bcbf4ef09063814af0c65d3e0585ada0
author Bram Moolenaar <Bram@vim.org> Fri Sep 11 19:28:19 2020 +0200
committer Bram Moolenaar <Bram@vim.org> Fri Sep 11 19:28:19 2020 +0200
tree 18f83c1a956186d3928e772cbd5d4cca6b72423a
parent c0c71e9d9813f025c5fc1ce84eae309843395199

patch 8.2.1661: cannot connect to 127.0.0.1 for host with only IPv6 addresses

Problem:    Cannot connect to 127.0.0.1 for host with only IPv6 addresses.
Solution:   pass AI_V4MAPPED flag to getaddrinfo. (Filipe Brandenburger,
            closes #6931)

src/channel.c

diff --git a/src/channel.c b/src/channel.c
index e73c415..bdb59f0 100644
--- a/src/channel.c
+++ b/src/channel.c
@@ -977,8 +977,8 @@
     CLEAR_FIELD(hints);
     hints.ai_family = AF_UNSPEC;
     hints.ai_socktype = SOCK_STREAM;
-# ifdef AI_ADDRCONFIG
-    hints.ai_flags = AI_ADDRCONFIG;
+# if defined(AI_ADDRCONFIG) && defined(AI_V4MAPPED)
+    hints.ai_flags = AI_ADDRCONFIG | AI_V4MAPPED;
 # endif
     // Set port number manually in order to prevent name resolution services
     // from being invoked in the environment where AI_NUMERICSERV is not