diff --git a/llvm/include/llvm/Analysis/RegionInfoImpl.h b/llvm/include/llvm/Analysis/RegionInfoImpl.h
--- a/llvm/include/llvm/Analysis/RegionInfoImpl.h
+++ b/llvm/include/llvm/Analysis/RegionInfoImpl.h
@@ -585,10 +585,8 @@
   // Exit is the header of a loop that contains the entry. In this case,
   // the dominance frontier must only contain the exit.
   if (!DT->dominates(entry, exit)) {
-    for (typename DST::iterator SI = entrySuccs->begin(),
-                                SE = entrySuccs->end();
-         SI != SE; ++SI) {
-      if (*SI != exit && *SI != entry)
+    for (BlockT *successor : *entrySuccs) {
+      if (successor != exit && successor != entry)
         return false;
     }