diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/debug/Debugger-ctor-04.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/debug/Debugger-ctor-04.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,5 @@
+// Repeated Debugger() arguments are ignored.
+
+var g = newGlobal();
+var dbg = Debugger(g, g, g);
+assertEq(dbg.getDebuggees().length, 1);