diff --git a/thirdparty/clipper2/Clipper2Lib/include/clipper2/clipper.engine.h b/thirdparty/clipper2/Clipper2Lib/include/clipper2/clipper.engine.h
index 2b0c79fdb2..33e4aced2b 100644
--- a/thirdparty/clipper2/Clipper2Lib/include/clipper2/clipper.engine.h
+++ b/thirdparty/clipper2/Clipper2Lib/include/clipper2/clipper.engine.h
@@ -22,6 +22,10 @@ constexpr auto CLIPPER2_VERSION = "1.2.1";
 
 #include "clipper.core.h"
 
+#ifdef None
+#undef None
+#endif
+
 namespace Clipper2Lib {
 
 	struct Scanline;