diff --git a/clang/include/clang/AST/Redeclarable.h b/clang/include/clang/AST/Redeclarable.h
index 091bb886f2d496..74ccd74ed60d6b 100644
--- a/clang/include/clang/AST/Redeclarable.h
+++ b/clang/include/clang/AST/Redeclarable.h
@@ -281,10 +281,10 @@ class Redeclarable {
       return tmp;
     }
 
-    friend bool operator==(redecl_iterator x, redecl_iterator y) {
+    friend bool operator==(const redecl_iterator &x, const redecl_iterator &y) {
       return x.Current == y.Current;
     }
-    friend bool operator!=(redecl_iterator x, redecl_iterator y) {
+    friend bool operator!=(const redecl_iterator &x, const redecl_iterator &y) {
       return x.Current != y.Current;
     }
   };