diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/collections/Set-clear-iterators-1.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/collections/Set-clear-iterators-1.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,23 @@
+// A Set iterator does not visit entries removed by clear().
+
+load(libdir + "iteration.js");
+
+var s = Set();
+var it = s[std_iterator]();
+s.clear();
+assertIteratorDone(it, undefined);
+
+s = Set(["a", "b", "c", "d"]);
+it = s[std_iterator]();
+assertIteratorNext(it, "a");
+s.clear();
+assertIteratorDone(it, undefined);
+
+var log = "";
+s = Set(["a", "b", "c", "d"]);
+for (var v of s) {
+    log += v;
+    if (v == "b")
+        s.clear();
+}
+assertEq(log, "ab");