diff --git a/SConstruct b/SConstruct
index 911e654ab..41d1d9f08 100644
--- a/SConstruct
+++ b/SConstruct
@@ -917,7 +917,7 @@ int main(int argc,char**argv){(void)argc;(void)argv;
 		Result('%s: building with %s' % (self.msgprefix, s))
 	def _result_check_user_setting(self,context,condition,CPPDEFINES,label,int=int,str=str):
 		if isinstance(CPPDEFINES, str):
-			context.sconf.Define(CPPDEFINES, int(condition))
+			self._define_macro(context, CPPDEFINES, int(condition))
 		elif condition:
 			self.successful_flags['CPPDEFINES'].extend(CPPDEFINES)
 		context.Result('%s: checking whether to enable %s...%s' % (self.msgprefix, label, 'yes' if condition else 'no'))
@@ -2064,8 +2064,12 @@ where the cast is useless.
 	def check_getaddrinfo_present(self,context,_successflags={'CPPDEFINES' : ['DXX_HAVE_GETADDRINFO']}):
 		self.Compile(context, text='''
 #ifdef WIN32
+#define DXX_WIN32_MINIMUM_WIN32_WINNT	0x0600
+#if defined(_WIN32_WINNT) && (_WIN32_WINNT < DXX_WIN32_MINIMUM_WIN32_WINNT)
+#undef _WIN32_WINNT
+#endif
 #ifndef _WIN32_WINNT
-#define _WIN32_WINNT 0x0501
+#define _WIN32_WINNT DXX_WIN32_MINIMUM_WIN32_WINNT
 #endif
 #include <winsock2.h>
 #include <ws2tcpip.h>
@@ -2076,8 +2080,15 @@ where the cast is useless.
 #endif
 ''', main='''
 	addrinfo *res = nullptr;
-	const addrinfo *hints = nullptr;
-	int i = getaddrinfo("", "", hints, &res);
+	addrinfo hints{};
+#ifdef AI_NUMERICSERV
+	/* Test that it is defined to a term that can be used with bit-or */
+	hints.ai_flags |= AI_NUMERICSERV;
+#endif
+#if DXX_USE_IPv6
+	hints.ai_flags |= AI_V4MAPPED | AI_ALL;
+#endif
+	int i = getaddrinfo("", "", &hints, &res);
 	(void)i;
 	freeaddrinfo(res);
 	return 0;
diff --git a/common/main/multi.h b/common/main/multi.h
index 023ab219a..31265b315 100644
--- a/common/main/multi.h
+++ b/common/main/multi.h
@@ -25,6 +25,7 @@ COPYRIGHT 1993-1999 PARALLAX SOFTWARE CORPORATION.  ALL RIGHTS RESERVED.
 
 #pragma once
 
+#include "dxxsconf.h"
 #include "fwd-player.h"
 #include "player-callsign.h"
 #include "player-flags.h"
@@ -37,10 +38,20 @@ COPYRIGHT 1993-1999 PARALLAX SOFTWARE CORPORATION.  ALL RIGHTS RESERVED.
 #include "game.h"
 
 #ifdef _WIN32
-#ifdef _WIN32_WINNT
+/* Require _WIN32_WINNT >= 0x0501 to enable getaddrinfo
+ * Require _WIN32_WINNT >= 0x0600 to enable some useful AI_* flags
+ */
+#ifdef DXX_HAVE_GETADDRINFO
+#define DXX_WIN32_MINIMUM_WIN32_WINNT	0x0600
+#else
+#define DXX_WIN32_MINIMUM_WIN32_WINNT	0x0500
+#endif
+#if defined(_WIN32_WINNT) && (_WIN32_WINNT < DXX_WIN32_MINIMUM_WIN32_WINNT)
 #undef _WIN32_WINNT
 #endif
-#define _WIN32_WINNT 0x0501 // for get/freeaddrinfo()
+#ifndef _WIN32_WINNT
+#define _WIN32_WINNT DXX_WIN32_MINIMUM_WIN32_WINNT
+#endif
 #include <winsock2.h>
 #include <ws2tcpip.h>
 #include <io.h>
diff --git a/similar/main/net_udp.cpp b/similar/main/net_udp.cpp
index ed105dcf5..db9e643ba 100644
--- a/similar/main/net_udp.cpp
+++ b/similar/main/net_udp.cpp
@@ -563,7 +563,12 @@ int udp_dns_filladdr_t::apply(sockaddr &addr, socklen_t addrlen, int ai_family,
 	hints.ai_family = ai_family;
 	// We are always UDP
 	hints.ai_socktype = SOCK_DGRAM;
-	hints.ai_flags = AI_V4MAPPED | AI_ALL | AI_NUMERICSERV;
+#ifdef AI_NUMERICSERV
+	hints.ai_flags |= AI_NUMERICSERV;
+#endif
+#if DXX_USE_IPv6
+	hints.ai_flags |= AI_V4MAPPED | AI_ALL;
+#endif
 	// Numeric address only?
 	if (numeric_only)
 		hints.ai_flags |= AI_NUMERICHOST;