diff --git a/include/llvm/Pass.h b/include/llvm/Pass.h
index 9663826ccf6..5c3eb478f6c 100644
--- a/include/llvm/Pass.h
+++ b/include/llvm/Pass.h
@@ -36,7 +36,7 @@
 #include <typeinfo>
 #include <cassert>
 
-#define USE_OLD_PASSMANAGER 1
+//#define USE_OLD_PASSMANAGER 1
 
 namespace llvm {