ThreadRestrictions: leak the thread local variable

base/lazy_instance.h

 // Copyright (c) 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.
 
 // The LazyInstance<Type, Traits> class manages a single instance of Type,
 // which will be lazily created on the first time it's accessed.  This class is
 // useful for places you would normally use a function-level static, but you
 // need to have guaranteed thread-safety.  The Type constructor will only ever
 // be called once, even if two threads are racing to create the object.  Get()
 // and Pointer() will always return the same, completely initialized instance.
@@ skipping 37 matching lines @@
     // Use placement new to initialize our instance in our preallocated space.
     // The parenthesis is very important here to force POD type initialization.
     return new (instance) Type();
   }
   static void Delete(void* instance) {
     // Explicitly call the destructor.
     reinterpret_cast<Type*>(instance)->~Type();
   }
 };
 
+template <typename Type>
+struct LeakyLazyInstanceTraits {
+  static Type* New(void* instance) {
+    return DefaultLazyInstanceTraits<Type>::New(instance);
+  }
+  // Rather than define an empty Delete function, we make Delete itself
+  // a null pointer.  This allows us to completely sidestep registering
+  // this object with an AtExitManager, which allows you to use
+  // LeakyLazyInstanceTraits in contexts where you don't have an
+  // AtExitManager.
+  static void (*Delete)(void* instance);
+};
+
+template <typename Type>
+void (*LeakyLazyInstanceTraits<Type>::Delete)(void* instance) = NULL;
+
 // We pull out some of the functionality into a non-templated base, so that we
 // can implement the more complicated pieces out of line in the .cc file.
 class LazyInstanceHelper {
  protected:
   enum {
     STATE_EMPTY    = 0,
     STATE_CREATING = 1,
     STATE_CREATED  = 2
   };
 
@@ skipping 49 matching lines @@
  private:
   int8 buf_[sizeof(Type)];  // Preallocate the space for the Type instance.
   Type *instance_;
 
   DISALLOW_COPY_AND_ASSIGN(LazyInstance);
 };
 
 }  // namespace base
 
 #endif  // BASE_LAZY_INSTANCE_H_