diff --git a/clang/lib/Frontend/ASTMerge.cpp b/clang/lib/Frontend/ASTMerge.cpp
index b6c644e..ff6434c 100644
--- a/clang/lib/Frontend/ASTMerge.cpp
+++ b/clang/lib/Frontend/ASTMerge.cpp
@@ -57,16 +57,14 @@
                          /*MinimalImport=*/false);
 
     TranslationUnitDecl *TU = Unit->getASTContext().getTranslationUnitDecl();
-    for (DeclContext::decl_iterator D = TU->decls_begin(), 
-                                 DEnd = TU->decls_end();
-         D != DEnd; ++D) {
+    for (auto *D : TU->decls()) {
       // Don't re-import __va_list_tag, __builtin_va_list.
-      if (NamedDecl *ND = dyn_cast<NamedDecl>(*D))
+      if (const auto *ND = dyn_cast<NamedDecl>(D))
         if (IdentifierInfo *II = ND->getIdentifier())
           if (II->isStr("__va_list_tag") || II->isStr("__builtin_va_list"))
             continue;
       
-      Importer.Import(*D);
+      Importer.Import(D);
     }
 
     delete Unit;