diff --git a/src/a2netcompat.h b/src/a2netcompat.h
index 01be9c25..3e2e8ccc 100644
--- a/src/a2netcompat.h
+++ b/src/a2netcompat.h
@@ -54,7 +54,9 @@
 
 #ifdef __MINGW32__
 # define a2_sockopt_t char *
-# define HAVE_GETADDRINFO
+# ifndef HAVE_GETADDRINFO
+#   define HAVE_GETADDRINFO
+# endif // !HAVE_GETADDRINFO
 # undef HAVE_GAI_STRERROR
 # undef gai_strerror
 #else