diff -r 000000000000 -r 6474c204b198 xpcom/tests/windows/TestCOM.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/xpcom/tests/windows/TestCOM.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,147 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <windows.h>
+#include <unknwn.h>
+#include <stdio.h>
+#include "nsISupports.h"
+#include "nsIFactory.h"
+
+// unknwn.h is needed to build with WIN32_LEAN_AND_MEAN
+#include <unknwn.h>
+
+// {5846BA30-B856-11d1-A98A-00805F8A7AC4}
+#define NS_ITEST_COM_IID \
+{ 0x5846ba30, 0xb856, 0x11d1, \
+  { 0xa9, 0x8a, 0x0, 0x80, 0x5f, 0x8a, 0x7a, 0xc4 } }
+
+class nsITestCom: public nsISupports
+{
+public:
+  NS_DECLARE_STATIC_IID_ACCESSOR(NS_ITEST_COM_IID)
+  NS_IMETHOD Test() = 0;
+};
+
+NS_DEFINE_STATIC_IID_ACCESSOR(nsITestCom, NS_ITEST_COM_IID)
+
+/*
+ * nsTestCom
+ */
+
+class nsTestCom MOZ_FINAL : public nsITestCom {
+  NS_DECL_ISUPPORTS
+
+public:
+  nsTestCom() {
+  }
+
+  NS_IMETHOD Test() {
+    printf("Accessed nsITestCom::Test() from COM\n");
+    return NS_OK;
+  }
+
+private:
+  ~nsTestCom() {
+    printf("nsTestCom instance successfully deleted\n");
+  }
+};
+
+NS_IMPL_QUERY_INTERFACE(nsTestCom, nsITestCom)
+
+MozExternalRefCountType nsTestCom::AddRef()
+{
+  nsrefcnt res = ++mRefCnt;
+  NS_LOG_ADDREF(this, mRefCnt, "nsTestCom", sizeof(*this));
+  printf("nsTestCom: Adding ref = %d\n", res);
+  return res;
+}
+
+MozExternalRefCountType nsTestCom::Release()
+{
+  nsrefcnt res = --mRefCnt;
+  NS_LOG_RELEASE(this, mRefCnt, "nsTestCom");
+  printf("nsTestCom: Releasing = %d\n", res);
+  if (res == 0) {
+    delete this;
+  }
+  return res;
+}
+
+class nsTestComFactory MOZ_FINAL : public nsIFactory {
+  NS_DECL_ISUPPORTS
+public:
+  nsTestComFactory() {
+  }
+  
+  NS_IMETHOD CreateInstance(nsISupports *aOuter,
+                            const nsIID &aIID,
+                            void **aResult);
+
+  NS_IMETHOD LockFactory(bool aLock) {
+    printf("nsTestComFactory: ");
+    printf("%s", (aLock ? "Locking server" : "Unlocking server"));
+    printf("\n");
+    return NS_OK;
+  }
+};
+
+NS_IMPL_ISUPPORTS(nsTestComFactory, nsIFactory)
+
+nsresult nsTestComFactory::CreateInstance(nsISupports *aOuter,
+					  const nsIID &aIID,
+					  void **aResult)
+{
+  if (aOuter != nullptr) {
+    return NS_ERROR_NO_AGGREGATION;
+  }
+
+  nsTestCom *t = new nsTestCom();
+  
+  if (t == nullptr) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+  
+  NS_ADDREF(t);
+  nsresult res = t->QueryInterface(aIID, aResult);
+  NS_RELEASE(t);
+
+  if (NS_SUCCEEDED(res)) {
+    printf("nsTestComFactory: successfully created nsTestCom instance\n");
+  }
+
+  return res;
+}
+
+/*
+ * main
+ */
+
+int main(int argc, char *argv[])
+{
+  nsTestComFactory *inst = new nsTestComFactory();
+  IClassFactory *iFactory;
+  inst->QueryInterface(NS_GET_IID(nsIFactory), (void **) &iFactory);
+
+  IUnknown *iUnknown;  
+  nsITestCom *iTestCom;
+
+  iFactory->LockServer(TRUE);
+  iFactory->CreateInstance(nullptr, IID_IUnknown, (void **) &iUnknown);
+  iFactory->LockServer(FALSE);
+
+  GUID testGUID = NS_ITEST_COM_IID;
+  HRESULT hres;
+  hres= iUnknown->QueryInterface(testGUID, 
+				 (void **) &iTestCom);
+
+  iTestCom->Test();
+
+  iUnknown->Release();
+  iTestCom->Release();
+  iFactory->Release();
+
+  return 0;
+}
+