Index: include/llvm/ADT/SmallPtrSet.h
===================================================================
--- include/llvm/ADT/SmallPtrSet.h
+++ include/llvm/ADT/SmallPtrSet.h
@@ -29,7 +29,7 @@
 #if LLVM_ENABLE_ABI_BREAKING_CHECKS
 namespace llvm {
 template <class T = void> struct ReverseIterate { static bool value; };
-template <class T> bool ReverseIterate<T>::value = true;
+template <class T> bool ReverseIterate<T>::value = false;
 }
 #endif
 
Index: lib/Support/CommandLine.cpp
===================================================================
--- lib/Support/CommandLine.cpp
+++ lib/Support/CommandLine.cpp
@@ -52,7 +52,7 @@
 // This will help uncover differences in codegen caused due to undefined
 // iteration order.
 static cl::opt<bool, true> ReverseIteration("reverse-iterate",
-  cl::location(ReverseIterate<bool>::value), cl::init(true));
+  cl::location(ReverseIterate<bool>::value), cl::init(false));
 }
 #endif