diff --git a/ext/standard/string.c b/ext/standard/string.c
index 4bdc04ac51d..f32c901a8e2 100644
--- a/ext/standard/string.c
+++ b/ext/standard/string.c
@@ -60,7 +60,7 @@ void register_string_constants(INIT_FUNC_ARGS)
 	REGISTER_LONG_CONSTANT("LC_COLLATE", LC_COLLATE, CONST_CS | CONST_PERSISTENT);
 	REGISTER_LONG_CONSTANT("LC_MONETARY", LC_MONETARY, CONST_CS | CONST_PERSISTENT);
 	REGISTER_LONG_CONSTANT("LC_ALL", LC_ALL, CONST_CS | CONST_PERSISTENT);
-# if !PHP_WIN32
+# ifdef LC_MESSAGES
 	REGISTER_LONG_CONSTANT("LC_MESSAGES", LC_MESSAGES, CONST_CS | CONST_PERSISTENT);
 # endif
 #endif