From c795750b29c923b3bb08eb8b93a44f1bc7646e98 Mon Sep 17 00:00:00 2001
From: Anders Carlsson <andersca@mac.com>
Date: Sat, 24 Apr 2010 22:02:54 +0000
Subject: [PATCH] When building implicit base initializers, add a
 derived-to-base cast that points to the exact base specifier.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@102277 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Sema/SemaDeclCXX.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index 6d1d1070fd..d7cbc17a7a 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -1502,6 +1502,13 @@ BuildImplicitBaseInitializer(Sema &SemaRef, CXXConstructorDecl *Constructor,
       DeclRefExpr::Create(SemaRef.Context, 0, SourceRange(), Param, 
                           SourceLocation(), ParamType, 0);
     
+    // Cast to the base class to avoid ambiguities.
+    CXXBaseSpecifierArray BasePath;
+    BasePath.push_back(BaseSpec);
+    SemaRef.ImpCastExprToType(CopyCtorArg, BaseSpec->getType(), 
+                              CastExpr::CK_UncheckedDerivedToBase,
+                              /*isLvalue=*/true, BasePath);
+
     InitializationKind InitKind
       = InitializationKind::CreateDirect(Constructor->getLocation(),
                                          SourceLocation(), SourceLocation());
-- 
2.50.0