constexpr: require 'this' to point to an object in a constexpr method call.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@149467 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/ExprConstant.cpp b/lib/AST/ExprConstant.cpp
index 8897667..0f8de63 100644
--- a/lib/AST/ExprConstant.cpp
+++ b/lib/AST/ExprConstant.cpp
@@ -127,7 +127,8 @@
 
   // The order of this enum is important for diagnostics.
   enum CheckSubobjectKind {
-    CSK_Base, CSK_Derived, CSK_Field, CSK_ArrayToPointer, CSK_ArrayIndex
+    CSK_Base, CSK_Derived, CSK_Field, CSK_ArrayToPointer, CSK_ArrayIndex,
+    CSK_This
   };
 
   /// A path from a glvalue to a subobject of that glvalue.
@@ -2362,6 +2363,9 @@
     } else
       return Error(E);
 
+    if (This && !This->checkSubobject(Info, E, CSK_This))
+      return false;
+
     const FunctionDecl *Definition = 0;
     Stmt *Body = FD->getBody(Definition);
     APValue Result;