diff --git a/extraParams.hxml b/extraParams.hxml
index 39a9c9e..8e12519 100644
--- a/extraParams.hxml
+++ b/extraParams.hxml
@@ -1,2 +1,3 @@
 --macro hxpy.macros.CopyFiles.run()
 -D CONFIG_64
+-D HXCPP_M64