diff --git a/thirdparty/libportfwd/third-party/miniupnpc-1.6/miniupnpc.c b/thirdparty/libportfwd/third-party/miniupnpc-1.6/miniupnpc.c
index bd46a2421..d87f469cd 100644
--- a/thirdparty/libportfwd/third-party/miniupnpc-1.6/miniupnpc.c
+++ b/thirdparty/libportfwd/third-party/miniupnpc-1.6/miniupnpc.c
@@ -16,6 +16,10 @@
 #endif
 #endif
 
+#ifdef __APPLE__
+#define _DARWIN_C_SOURCE
+#endif
+
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>