diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/collections/Map-iterator-remove-2.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/collections/Map-iterator-remove-2.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,13 @@
+// A map iterator can cope with removing the next entry.
+
+load(libdir + "iteration.js");
+
+var map = Map([['a', 0], ['b', 1], ['c', 2], ['d', 3]]);
+var iter = map[std_iterator]();
+var log = '';
+for (let [k, v] of iter) {
+    log += k + v;
+    if (k === 'b')
+        map.delete('c');
+}
+assertEq(log, 'a0b1d3');