Check in a test case and a nasty workaround for PR6199.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@95076 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGExprCXX.cpp b/lib/CodeGen/CGExprCXX.cpp
index 4253d18..8dd7472 100644
--- a/lib/CodeGen/CGExprCXX.cpp
+++ b/lib/CodeGen/CGExprCXX.cpp
@@ -309,7 +309,9 @@
   if (getContext().getLangOptions().ElideConstructors && E->isElidable()) {
     const Expr *Arg = E->getArg(0);
     
-    if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(Arg)) {
+    // FIXME: This 'while' statement should really be an 'if' statement, it's 
+    // added as a workaround for PR6199.
+    while (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(Arg)) {
       assert((ICE->getCastKind() == CastExpr::CK_NoOp ||
               ICE->getCastKind() == CastExpr::CK_ConstructorConversion ||
               ICE->getCastKind() == CastExpr::CK_UserDefinedConversion) &&