From ed4fb26d755e98d117e81ec0a10a7f4aa729f45f Mon Sep 17 00:00:00 2001
From: "Yukihiro \"Matz\" Matsumoto" <matz@ruby.or.jp>
Date: Thu, 16 Oct 2025 16:54:11 +0900
Subject: [PATCH] hal-win-socket: guard _WIN32_WINNT definition to prevent
 redefinition

only define _WIN32_WINNT if not already defined. mingw headers may
predefine this macro, causing redefinition warning.

Co-authored-by: Claude <noreply@anthropic.com>
---
 mrbgems/hal-win-socket/src/socket_hal.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/mrbgems/hal-win-socket/src/socket_hal.c b/mrbgems/hal-win-socket/src/socket_hal.c
index 7dd7e586b..cfd467b34 100644
--- a/mrbgems/hal-win-socket/src/socket_hal.c
+++ b/mrbgems/hal-win-socket/src/socket_hal.c
@@ -14,7 +14,9 @@
 #include <mruby/presym.h>
 #include "socket_hal.h"
 
+#ifndef _WIN32_WINNT
 #define _WIN32_WINNT 0x0501
+#endif
 #include <winsock2.h>
 #include <ws2tcpip.h>
 #include <windows.h>