From 32ed3e9e97c7ca90c324cc9e4cd7e0437a965919 Mon Sep 17 00:00:00 2001
From: Brian Hackett <bhackett1024@gmail.com>
Date: Wed, 16 Mar 2011 19:26:49 -0700
Subject: [PATCH] [INFER] Mark unexpected undefined result for JSON.stringify,
 bug 642161.

---
 js/src/jit-test/tests/basic/bug642161.js | 1 +
 js/src/json.cpp                          | 2 ++
 2 files changed, 3 insertions(+)
 create mode 100644 js/src/jit-test/tests/basic/bug642161.js

diff --git a/js/src/jit-test/tests/basic/bug642161.js b/js/src/jit-test/tests/basic/bug642161.js
new file mode 100644
index 00000000000..18679dd9ed2
--- /dev/null
+++ b/js/src/jit-test/tests/basic/bug642161.js
@@ -0,0 +1 @@
+assertEq(JSON.stringify(0 | "prefix" || Boolean), undefined);
diff --git a/js/src/json.cpp b/js/src/json.cpp
index 71cdf5794b8..af3fb46fe09 100644
--- a/js/src/json.cpp
+++ b/js/src/json.cpp
@@ -162,6 +162,8 @@ js_json_stringify(JSContext *cx, uintN argc, Value *vp)
             return JS_FALSE;
         vp->setString(str);
     } else {
+        if (!cx->markTypeCallerUnexpected(types::TYPE_UNDEFINED))
+            return JS_FALSE;
         vp->setUndefined();
     }