C++1y: Allow aggregates to have default initializers.

Add a CXXDefaultInitExpr, analogous to CXXDefaultArgExpr, and use it both in
CXXCtorInitializers and in InitListExprs to represent a default initializer.

There's an additional complication here: because the default initializer can
refer to the initialized object via its 'this' pointer, we need to make sure
that 'this' points to the right thing within the evaluation.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179958 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/ExprClassification.cpp b/lib/AST/ExprClassification.cpp
index c2a35f4..bcb6d4e 100644
--- a/lib/AST/ExprClassification.cpp
+++ b/lib/AST/ExprClassification.cpp
@@ -298,6 +298,10 @@
   case Expr::CXXDefaultArgExprClass:
     return ClassifyInternal(Ctx, cast<CXXDefaultArgExpr>(E)->getExpr());
 
+    // Same idea for default initializers.
+  case Expr::CXXDefaultInitExprClass:
+    return ClassifyInternal(Ctx, cast<CXXDefaultInitExpr>(E)->getExpr());
+
     // Same idea for temporary binding.
   case Expr::CXXBindTemporaryExprClass:
     return ClassifyInternal(Ctx, cast<CXXBindTemporaryExpr>(E)->getSubExpr());