3 files changed, 13 insertions, 12 deletions
diff --git a/js/src/jsstr.cpp b/js/src/jsstr.cpp
index fdb62a679..74f61b87d 100644
--- a/js/src/jsstr.cpp
+++ b/js/src/jsstr.cpp
@@ -2918,7 +2918,10 @@ js::InitStringClass(JSContext* cx, HandleObject obj)
 
     Rooted<JSString*> empty(cx, cx->runtime()->emptyString);
     RootedObject proto(cx, GlobalObject::createBlankPrototype(cx, global, &StringObject::class_));
-    if (!proto || !proto->as<StringObject>().init(cx, empty))
+    if (!proto)
+        return nullptr;
+    Handle<StringObject*> protoObj = proto.as<StringObject>();
+    if (!StringObject::init(cx, protoObj, empty))
         return nullptr;
 
     /* Now create the String function. */
diff --git a/js/src/vm/StringObject-inl.h b/js/src/vm/StringObject-inl.h
index 5fc1656f6..38191fc7a 100644
--- a/js/src/vm/StringObject-inl.h
+++ b/js/src/vm/StringObject-inl.h
@@ -15,31 +15,29 @@
 
 namespace js {
 
-inline bool
-StringObject::init(JSContext* cx, HandleString str)
+/* static */ inline bool
+StringObject::init(JSContext* cx, Handle<StringObject*> obj, HandleString str)
 {
-    MOZ_ASSERT(numFixedSlots() == 2);
+    MOZ_ASSERT(obj->numFixedSlots() == 2);
 
-    Rooted<StringObject*> self(cx, this);
-
-    if (!EmptyShape::ensureInitialCustomShape<StringObject>(cx, self))
+    if (!EmptyShape::ensureInitialCustomShape<StringObject>(cx, obj))
         return false;
 
-    MOZ_ASSERT(self->lookup(cx, NameToId(cx->names().length))->slot() == LENGTH_SLOT);
+    MOZ_ASSERT(obj->lookup(cx, NameToId(cx->names().length))->slot() == LENGTH_SLOT);
 
-    self->setStringThis(str);
+    obj->setStringThis(str);
 
     return true;
 }
 
-inline StringObject*
+/* static */ inline StringObject*
 StringObject::create(JSContext* cx, HandleString str, HandleObject proto, NewObjectKind newKind)
 {
     JSObject* obj = NewObjectWithClassProto(cx, &class_, proto, newKind);
     if (!obj)
         return nullptr;
     Rooted<StringObject*> strobj(cx, &obj->as<StringObject>());
-    if (!strobj->init(cx, str))
+    if (!StringObject::init(cx, strobj, str))
         return nullptr;
     return strobj;
 }
diff --git a/js/src/vm/StringObject.h b/js/src/vm/StringObject.h
index 119e3d9fa..561e0478a 100644
--- a/js/src/vm/StringObject.h
+++ b/js/src/vm/StringObject.h
@@ -56,7 +56,7 @@ class StringObject : public NativeObject
     }
 
   private:
-    inline bool init(JSContext* cx, HandleString str);
+    static inline bool init(JSContext* cx, Handle<StringObject*> obj, HandleString str);
 
     void setStringThis(JSString* str) {
         MOZ_ASSERT(getReservedSlot(PRIMITIVE_VALUE_SLOT).isUndefined());