diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/generators/yield-yield.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/generators/yield-yield.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,12 @@
+// Bug 880447
+
+load(libdir + "asserts.js");
+
+function f() {
+    yield yield 1;
+}
+
+var g = f();
+assertEq(g.next(), 1);
+assertEq(g.send("hello"), "hello");
+assertThrowsValue(() => g.next(), StopIteration);