Deal with a horrible C++11 special case. If a non-literal type has a constexpr

constructor, and that constructor is used to initialize an object of static
storage duration such that all members and bases are initialized by constant
expressions, constant initialization is performed. In this case, the object
can still have a non-trivial destructor, and if it does, we must emit a dynamic
initializer which performs no initialization and instead simply registers that
destructor.

llvm-svn: 150419

1 files changed, 9 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CGExprConstant.cpp b/clang/lib/CodeGen/CGExprConstant.cpp
index ccb4b930e67..0b3ac9cbe5c 100644
--- a/clang/lib/CodeGen/CGExprConstant.cpp
+++ b/clang/lib/CodeGen/CGExprConstant.cpp
@@ -939,6 +939,15 @@ llvm::Constant *CodeGenModule::EmitConstantInit(const VarDecl &D,
   if (const APValue *Value = D.evaluateValue())
     return EmitConstantValue(*Value, D.getType(), CGF);
 
+  // FIXME: Implement C++11 [basic.start.init]p2: if the initializer of a
+  // reference is a constant expression, and the reference binds to a temporary,
+  // then constant initialization is performed. ConstExprEmitter will
+  // incorrectly emit a prvalue constant in this case, and the calling code
+  // interprets that as the (pointer) value of the reference, rather than the
+  // desired value of the referee.
+  if (D.getType()->isReferenceType())
+    return 0;
+
   const Expr *E = D.getInit();
   assert(E && "No initializer to emit");