diff --git a/CXX/yapi.hh b/CXX/yapi.hh
index ad65f4e4e..0ff85d192 100644
--- a/CXX/yapi.hh
+++ b/CXX/yapi.hh
@@ -78,10 +78,6 @@ extern "C" {
 #endif
 
 
-#ifdef CACHE_REGS
-#undef CACHE_REGS
-#endif 
-
 // taken from yap_structs.h
 #include "iopreds.h"