--- a/dom/plugins/ipc/PluginInstanceChild.cpp
+++ b/dom/plugins/ipc/PluginInstanceChild.cpp
@@ -980,17 +980,17 @@ PluginInstanceChild::AnswerNPP_SetWindow
     mWsInfo.colormap = aWindow.colormap;
     if (!XVisualIDToInfo(mWsInfo.display, aWindow.visualID,
                          &mWsInfo.visual, &mWsInfo.depth))
         return false;
 
 #ifdef MOZ_WIDGET_GTK2
     if (gtk_check_version(2,18,7) != NULL) { // older
         if (aWindow.type == NPWindowTypeWindow) {
-            GdkWindow* socket_window = gdk_window_lookup(aWindow.window);
+            GdkWindow* socket_window = gdk_window_lookup(static_cast<GdkNativeWindow>(aWindow.window));
             if (socket_window) {
                 // A GdkWindow for the socket already exists.  Need to
                 // workaround https://bugzilla.gnome.org/show_bug.cgi?id=607061
                 // See wrap_gtk_plug_embedded in PluginModuleChild.cpp.
                 g_object_set_data(G_OBJECT(socket_window),
                                   "moz-existed-before-set-window",
                                   GUINT_TO_POINTER(1));
             }
@@ -1034,17 +1034,17 @@ PluginInstanceChild::AnswerNPP_SetWindow
               aWindow.height == 0) {
             // Skip SetWindow call for hidden QuickTime plugins
             return true;
           }
 
           if (!CreatePluginWindow())
               return false;
 
-          ReparentPluginWindow((HWND)aWindow.window);
+          ReparentPluginWindow(reinterpret_cast<HWND>(aWindow.window));
           SizePluginWindow(aWindow.width, aWindow.height);
 
           mWindow.window = (void*)mPluginWindowHWND;
           mWindow.x = aWindow.x;
           mWindow.y = aWindow.y;
           mWindow.width = aWindow.width;
           mWindow.height = aWindow.height;
           mWindow.type = aWindow.type;

--- a/dom/plugins/ipc/PluginInstanceParent.cpp
+++ b/dom/plugins/ipc/PluginInstanceParent.cpp
@@ -599,17 +599,17 @@ PluginInstanceParent::RecvShow(const NPR
     return true;
 }
 
 nsresult
 PluginInstanceParent::AsyncSetWindow(NPWindow* aWindow)
 {
     NPRemoteWindow window;
     mWindowType = aWindow->type;
-    window.window = reinterpret_cast<uintptr_t>(aWindow->window);
+    window.window = reinterpret_cast<uint64_t>(aWindow->window);
     window.x = aWindow->x;
     window.y = aWindow->y;
     window.width = aWindow->width;
     window.height = aWindow->height;
     window.clipRect = aWindow->clipRect;
     window.type = aWindow->type;
     if (!SendAsyncSetWindow(gfxPlatform::GetPlatform()->ScreenReferenceSurface()->GetType(),
                             window))
@@ -906,25 +906,25 @@ PluginInstanceParent::NPP_SetWindow(cons
         // SharedSurfaceSetWindow will take care of NPRemoteWindow.
         if (!SharedSurfaceSetWindow(aWindow, window)) {
           return NPERR_OUT_OF_MEMORY_ERROR;
         }
     }
     else {
         SubclassPluginWindow(reinterpret_cast<HWND>(aWindow->window));
 
-        window.window = reinterpret_cast<uintptr_t>(aWindow->window);
+        window.window = reinterpret_cast<uint64_t>(aWindow->window);
         window.x = aWindow->x;
         window.y = aWindow->y;
         window.width = aWindow->width;
         window.height = aWindow->height;
         window.type = aWindow->type;
     }
 #else
-    window.window = reinterpret_cast<unsigned long>(aWindow->window);
+    window.window = reinterpret_cast<uint64_t>(aWindow->window);
     window.x = aWindow->x;
     window.y = aWindow->y;
     window.width = aWindow->width;
     window.height = aWindow->height;
     window.clipRect = aWindow->clipRect; // MacOS specific
     window.type = aWindow->type;
 #endif
 

--- a/dom/plugins/ipc/PluginMessageUtils.h
+++ b/dom/plugins/ipc/PluginMessageUtils.h
@@ -105,17 +105,17 @@ struct IPCByteRange
 };  
 
 typedef std::vector<IPCByteRange> IPCByteRanges;
 
 typedef nsCString Buffer;
 
 struct NPRemoteWindow
 {
-  unsigned long window;
+  uint64_t window;
   int32_t x;
   int32_t y;
   uint32_t width;
   uint32_t height;
   NPRect clipRect;
   NPWindowType type;
 #if defined(MOZ_X11) && defined(XP_UNIX) && !defined(XP_MACOSX)
   VisualID visualID;
@@ -358,17 +358,17 @@ struct ParamTraits<NPWindowType>
 
 template <>
 struct ParamTraits<mozilla::plugins::NPRemoteWindow>
 {
   typedef mozilla::plugins::NPRemoteWindow paramType;
 
   static void Write(Message* aMsg, const paramType& aParam)
   {
-    aMsg->WriteULong(aParam.window);
+    aMsg->WriteUInt64(aParam.window);
     WriteParam(aMsg, aParam.x);
     WriteParam(aMsg, aParam.y);
     WriteParam(aMsg, aParam.width);
     WriteParam(aMsg, aParam.height);
     WriteParam(aMsg, aParam.clipRect);
     WriteParam(aMsg, aParam.type);
 #if defined(MOZ_X11) && defined(XP_UNIX) && !defined(XP_MACOSX)
     aMsg->WriteULong(aParam.visualID);
@@ -376,22 +376,22 @@ struct ParamTraits<mozilla::plugins::NPR
 #endif
 #if defined(XP_WIN)
     WriteParam(aMsg, aParam.surfaceHandle);
 #endif
   }
 
   static bool Read(const Message* aMsg, void** aIter, paramType* aResult)
   {
-    unsigned long window;
+    uint64_t window;
     int32_t x, y;
     uint32_t width, height;
     NPRect clipRect;
     NPWindowType type;
-    if (!(aMsg->ReadULong(aIter, &window) &&
+    if (!(aMsg->ReadUInt64(aIter, &window) &&
           ReadParam(aMsg, aIter, &x) &&
           ReadParam(aMsg, aIter, &y) &&
           ReadParam(aMsg, aIter, &width) &&
           ReadParam(aMsg, aIter, &height) &&
           ReadParam(aMsg, aIter, &clipRect) &&
           ReadParam(aMsg, aIter, &type)))
       return false;