diff -r 000000000000 -r 6474c204b198 js/src/gdb/tests/test-JSObject.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/gdb/tests/test-JSObject.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,40 @@
+#include "gdb-tests.h"
+#include "jsapi.h"
+
+FRAGMENT(JSObject, simple) {
+  JS::Rooted<JSObject *> glob(cx, JS::CurrentGlobalOrNull(cx));
+  JS::Rooted<JSObject *> plain(cx, JS_NewObject(cx, nullptr, JS::NullPtr(), JS::NullPtr()));
+  JS::Rooted<JSObject *> global(cx, JS::CurrentGlobalOrNull(cx));
+  JS::Rooted<JSObject *> func(cx, (JSObject *) JS_NewFunction(cx, (JSNative) 1, 0, 0,
+                                                              global, "dys"));
+  JS::Rooted<JSObject *> anon(cx, (JSObject *) JS_NewFunction(cx, (JSNative) 1, 0, 0, global, 0));
+  JS::Rooted<JSFunction *> funcPtr(cx, JS_NewFunction(cx, (JSNative) 1, 0, 0,
+                                                      global, "formFollows"));
+
+  JSObject &plainRef = *plain;
+  JSFunction &funcRef = *funcPtr;
+  JSObject *plainRaw = plain;
+  JSObject *funcRaw = func;
+
+  breakpoint();
+
+  (void) glob;
+  (void) plain;
+  (void) func;
+  (void) anon;
+  (void) funcPtr;
+  (void) &plainRef;
+  (void) &funcRef;
+  (void) plainRaw;
+  (void) funcRaw;
+}
+
+FRAGMENT(JSObject, null) {
+  JS::Rooted<JSObject *> null(cx, nullptr);
+  JSObject *nullRaw = null;
+
+  breakpoint();
+
+  (void) null;
+  (void) nullRaw;
+}