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

base/path_service.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 "base/path_service.h"
 
 #ifdef OS_WIN
 #include <windows.h>
 #include <shellapi.h>
 #include <shlobj.h>
 #endif
 
 #include "base/file_path.h"
 #include "base/file_util.h"
 #include "base/hash_tables.h"
+#include "base/lazy_instance.h"
 #include "base/lock.h"
 #include "base/logging.h"
-#include "base/singleton.h"
 
 namespace base {
   bool PathProvider(int key, FilePath* result);
 #if defined(OS_WIN)
   bool PathProviderWin(int key, FilePath* result);
 #elif defined(OS_MACOSX)
   bool PathProviderMac(int key, FilePath* result);
 #elif defined(OS_POSIX)
   bool PathProviderPosix(int key, FilePath* result);
 #endif
@@ skipping 82 matching lines @@
     Provider* p = providers;
     while (p) {
       Provider* next = p->next;
       if (!p->is_static)
         delete p;
       p = next;
     }
   }
 };
 
+static base::LazyInstance<PathData> g_path_data(base::LINKER_INITIALIZED);
+
 static PathData* GetPathData() {
-  return Singleton<PathData>::get();
+  return g_path_data.Pointer();
 }
 
 }  // namespace
 
 
 // static
 bool PathService::GetFromCache(int key, FilePath* result) {
   PathData* path_data = GetPathData();
   AutoLock scoped_lock(path_data->lock);
 
@@ skipping 124 matching lines @@
   p = new Provider;
   p->is_static = false;
   p->func = func;
   p->next = path_data->providers;
 #ifndef NDEBUG
   p->key_start = key_start;
   p->key_end = key_end;
 #endif
   path_data->providers = p;
 }