diff --git a/include/clang/Sema/Sema.h b/include/clang/Sema/Sema.h
index c845ee5..8ac7c3e 100644
--- a/include/clang/Sema/Sema.h
+++ b/include/clang/Sema/Sema.h
@@ -6556,11 +6556,11 @@
   /// and reports the appropriate diagnostics. Returns false on success.
   /// Can optionally return the value of the expression.
   ExprResult VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
-                                             PartialDiagnostic Diag,
+                                             const PartialDiagnostic &Diag,
                                              bool AllowFold,
-                                             PartialDiagnostic FoldDiag);
+                                             const PartialDiagnostic &FoldDiag);
   ExprResult VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
-                                             PartialDiagnostic Diag,
+                                             const PartialDiagnostic &Diag,
                                              bool AllowFold = true) {
     return VerifyIntegerConstantExpression(E, Result, Diag, AllowFold,
                                            PDiag(0));
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index fd54499..669ba3a 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -9438,10 +9438,11 @@
       PDiag(diag::err_expr_not_ice) << LangOpts.CPlusPlus);
 }
 
-ExprResult Sema::VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
-                                                 PartialDiagnostic NotIceDiag,
-                                                 bool AllowFold,
-                                                 PartialDiagnostic FoldDiag) {
+ExprResult
+Sema::VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
+                                      const PartialDiagnostic &NotIceDiag,
+                                      bool AllowFold,
+                                      const PartialDiagnostic &FoldDiag) {
   SourceLocation DiagLoc = E->getLocStart();
 
   if (getLangOpts().CPlusPlus0x) {