From 29361c055ac00fe678cb2ab0e14e9a71fba6baa1 Mon Sep 17 00:00:00 2001
From: Ingvar Stepanyan <me@rreverser.com>
Date: Sun, 8 Feb 2015 11:56:15 +0200
Subject: [PATCH] Fix #718.

---
 lib/6to5/transformation/templates/tail-call.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/6to5/transformation/templates/tail-call.js b/lib/6to5/transformation/templates/tail-call.js
index e606340503..86fd368be2 100644
--- a/lib/6to5/transformation/templates/tail-call.js
+++ b/lib/6to5/transformation/templates/tail-call.js
@@ -5,6 +5,8 @@
     this.context = context;
   }
 
+  Tail.prototype._isTailDescriptor = true;
+
   var isRunning = false;
 
   return function (func, args, context) {
@@ -13,7 +15,7 @@
       isRunning = true;
       do {
         result = result.func.apply(result.context, result.args);
-      } while (result instanceof Tail);
+      } while (result instanceof Tail || (result && result._isTailDescriptor));
       isRunning = false;
     }
     return result;