diff --git a/include/osg/GraphicsContext b/include/osg/GraphicsContext
index ac196d5a8..33d7b0b12 100644
--- a/include/osg/GraphicsContext
+++ b/include/osg/GraphicsContext
@@ -597,6 +597,10 @@ struct WindowingSystemInterfaceProxy
     osg::ref_ptr<T> _wsi;
 };
 
+#define REGISTER_WINDOWINGSYSTEMINTERFACE(ext, classname) \
+    extern "C" void graphicswindow_##ext(void) {} \
+    static osg::WindowingSystemInterfaceProxy<classname> s_proxy_##classname(#ext);
+
 }
 
 #endif
diff --git a/include/osgViewer/GraphicsWindow b/include/osgViewer/GraphicsWindow
index 2ee2f24c0..b09f56e5e 100644
--- a/include/osgViewer/GraphicsWindow
+++ b/include/osgViewer/GraphicsWindow
@@ -274,10 +274,6 @@ class GraphicsWindowEmbedded : public GraphicsWindow
 };
 
 
-#define REGISTER_WINDOWINGSYSTEMINTERFACE(ext, classname) \
-    extern "C" OSGVIEWER_EXPORT void graphicswindow_##ext(void) {} \
-    static osg::WindowingSystemInterfaceProxy<classname> s_proxy_##classname(#ext);
-
 struct GraphicsWindowFunctionProxy
 {
     GraphicsWindowFunctionProxy(CGraphicsWindowFunction function) { (function)(); }
diff --git a/src/osgViewer/GraphicsWindowWin32.cpp b/src/osgViewer/GraphicsWindowWin32.cpp
index 035258dcd..91e6c8f49 100644
--- a/src/osgViewer/GraphicsWindowWin32.cpp
+++ b/src/osgViewer/GraphicsWindowWin32.cpp
@@ -3147,15 +3147,9 @@ static RegisterWindowingSystemInterfaceProxy createWindowingSystemInterfaceProxy
 
 } // namespace OsgViewer
 
-#if 1
-REGISTER_WINDOWINGSYSTEMINTERFACE(Win32, Win32WindowingSystem)
-#else
-// declare C entry point for static compilation.
-extern "C" void OSGVIEWER_EXPORT graphicswindow_Win32(void)
-{
-    osg::GraphicsContext::setWindowingSystemInterface(osgViewer::Win32WindowingSystem::getInterface());
-}
-#endif
+
+extern "C" OSGVIEWER_EXPORT void graphicswindow_Win32(void) {}
+static osg::WindowingSystemInterfaceProxy<Win32WindowingSystem> s_proxy_Win32WindowingSystem("Win32");
 
 void GraphicsWindowWin32::raiseWindow()
 {