From 7ff2bcb81424a6f9cded249b14b817ea25c37dcc Mon Sep 17 00:00:00 2001
From: Richard Smith <richard-llvm@metafoo.co.uk>
Date: Fri, 24 Jan 2014 01:54:52 +0000
Subject: [PATCH] PR18560: When switching to a new context, don't just save and
 restore an override for the type of 'this', also clear it out (unless we're
 entering the context of a lambda-expression, where it should be inherited).

llvm-svn: 199962
---
 clang/include/clang/Sema/Sema.h    |  4 +++-
 clang/lib/Sema/TreeTransform.h     |  3 ++-
 clang/test/SemaCXX/member-init.cpp | 10 ++++++++++
 3 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index f11cb9ca93a0..12a4116f01fb 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -479,13 +479,15 @@ public:
     QualType SavedCXXThisTypeOverride;
 
   public:
-    ContextRAII(Sema &S, DeclContext *ContextToPush)
+    ContextRAII(Sema &S, DeclContext *ContextToPush, bool NewThisContext = true)
       : S(S), SavedContext(S.CurContext),
         SavedContextState(S.DelayedDiagnostics.pushUndelayed()),
         SavedCXXThisTypeOverride(S.CXXThisTypeOverride)
     {
       assert(ContextToPush && "pushing null context");
       S.CurContext = ContextToPush;
+      if (NewThisContext)
+        S.CXXThisTypeOverride = QualType();
     }
 
     void pop() {
diff --git a/clang/lib/Sema/TreeTransform.h b/clang/lib/Sema/TreeTransform.h
index 787581d35be4..27380f8c8d44 100644
--- a/clang/lib/Sema/TreeTransform.h
+++ b/clang/lib/Sema/TreeTransform.h
@@ -8339,7 +8339,8 @@ TreeTransform<Derived>::TransformLambdaScope(LambdaExpr *E,
   bool Invalid = false;
 
   // Introduce the context of the call operator.
-  Sema::ContextRAII SavedContext(getSema(), CallOperator);
+  Sema::ContextRAII SavedContext(getSema(), CallOperator,
+                                 /*NewThisContext*/false);
 
   LambdaScopeInfo *const LSI = getSema().getCurLambda();
   // Enter the scope of the lambda.
diff --git a/clang/test/SemaCXX/member-init.cpp b/clang/test/SemaCXX/member-init.cpp
index 6e4fd5df5a08..d8a00b3b1e24 100644
--- a/clang/test/SemaCXX/member-init.cpp
+++ b/clang/test/SemaCXX/member-init.cpp
@@ -100,3 +100,13 @@ namespace rdar14084171 {
   };
   void f(Sprite& x) { x = x; }
 }
+
+namespace PR18560 {
+  struct X { int m; };
+
+  template<typename T = X,
+           typename U = decltype(T::m)>
+  int f();
+
+  struct Y { int b = f(); };
+}