diff --git a/platform_mac/mac_4ed.m b/platform_mac/mac_4ed.m
index 924afc64..6077de47 100644
--- a/platform_mac/mac_4ed.m
+++ b/platform_mac/mac_4ed.m
@@ -16,6 +16,8 @@
 
 #undef internal
 #undef global
+#undef external
+#define external
 
 #include "osx_objective_c_to_cpp_links.h"