diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/debug/Environment-gc-01.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/debug/Environment-gc-01.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,19 @@
+// An Environment keeps its referent alive.
+
+var g = newGlobal();
+g.eval("function f(x) { return 2 * x; }");
+var dbg = Debugger(g);
+var env;
+dbg.onEnterFrame = function (frame) { env = frame.environment; };
+assertEq(g.f(22), 44);
+dbg.onEnterFrame = undefined;
+
+assertEq(env.find("x"), env);
+assertEq(env.names().join(","), "arguments,x");
+
+gc();
+g.gc(g);
+gc(env);
+
+assertEq(env.find("x"), env);
+assertEq(env.names().join(","), "arguments,x");