From 5adda836af9e4368973473d7974f245688d6932b Mon Sep 17 00:00:00 2001
From: Sebastian McKenzie <sebmck@gmail.com>
Date: Mon, 13 Apr 2015 09:21:59 -0700
Subject: [PATCH] don't do TCO on generators and async functions - fixes #1251

---
 src/babel/transformation/transformers/es6/tail-call.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/babel/transformation/transformers/es6/tail-call.js b/src/babel/transformation/transformers/es6/tail-call.js
index 6e9fabafb4..91f6d3040b 100644
--- a/src/babel/transformation/transformers/es6/tail-call.js
+++ b/src/babel/transformation/transformers/es6/tail-call.js
@@ -6,6 +6,7 @@ import map from "lodash/collection/map";
 import * as t from "../../../types";
 
 exports.Function = function (node, parent, scope, file) {
+  if (node.generator || node.async) return;
   var tailCall = new TailCallTransformer(this, scope, file);
   tailCall.run();
 };