diff --git a/fex/fex/blargg_common.h b/fex/fex/blargg_common.h
index 6b5370b6..885b41f6 100644
--- a/fex/fex/blargg_common.h
+++ b/fex/fex/blargg_common.h
@@ -12,7 +12,7 @@
 typedef const char *blargg_err_t; // 0 on success, otherwise error string
 
 // Success; no error
-int const blargg_ok = 0;
+#define blargg_ok NULL
 
 // BLARGG_RESTRICT: equivalent to C99's restrict, where supported
 #if __GNUC__ >= 3 || _MSC_VER >= 1100