Make members of Singleton<T> private and only visible to the singleton type.

net/base/winsock_init.cc

 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <winsock2.h>
 
 #include "net/base/winsock_init.h"
 
+#include "base/lazy_instance.h"
 #include "base/logging.h"
-#include "base/singleton.h"
 
 namespace {
 
 class WinsockInitSingleton {
  public:
   WinsockInitSingleton() {
     WORD winsock_ver = MAKEWORD(2, 2);
     WSAData wsa_data;
     bool did_init = (WSAStartup(winsock_ver, &wsa_data) == 0);
     if (did_init) {
       DCHECK(wsa_data.wVersion == winsock_ver);
 
       // The first time WSAGetLastError is called, the delay load helper will
       // resolve the address with GetProcAddress and fixup the import.  If a
       // third party application hooks system functions without correctly
       // restoring the error code, it is possible that the error code will be
       // overwritten during delay load resolution.  The result of the first
       // call may be incorrect, so make sure the function is bound and future
       // results will be correct.
       WSAGetLastError();
     }
   }
 
   ~WinsockInitSingleton() {
     // Don't call WSACleanup() since the worker pool threads can continue to
     // call getaddrinfo() after Winsock has shutdown, which can lead to crashes.
   }
 };
 
+static base::LazyInstance<WinsockInitSingleton> g_winsock_init_singleton(
+    base::LINKER_INITIALIZED);
+
 }  // namespace
 
 namespace net {
 
 void EnsureWinsockInit() {
-  Singleton<WinsockInitSingleton>::get();
+  g_winsock_init_singleton.Get();
 }
 
 }  // namespace net