Index: llvm/include/llvm/ADT/SetOperations.h
===================================================================
--- llvm/include/llvm/ADT/SetOperations.h
+++ llvm/include/llvm/ADT/SetOperations.h
@@ -71,7 +71,7 @@
 bool set_is_subset(const S1Ty &S1, const S2Ty &S2) {
   if (S1.size() > S2.size())
     return false;
-  for (const auto &It : S1)
+  for (const auto It : S1)
     if (!S2.count(It))
       return false;
   return true;