diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/collections/Set-iterator-gc-3.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/collections/Set-iterator-gc-3.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,20 @@
+// GC in nested for-loops is safe.
+
+var x;
+for (x of Set([1]))
+    for (x of Set([1]))
+        for (x of Set([1]))
+            for (x of Set([1]))
+                for (x of Set([1]))
+                    for (x of Set([1]))
+                        for (x of Set([1]))
+                            for (x of Set([1]))
+                                for (x of Set([1]))
+                                    for (x of Set([1]))
+                                        for (x of Set([1]))
+                                            for (x of Set([1]))
+                                                for (x of Set([1]))
+                                                    for (x of Set([1]))
+                                                        for (x of Set([1]))
+                                                            for (x of Set([1]))
+                                                                gc();