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// Copyright (C) 2000 Stephen Cleary
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// See for updates, documentation, and revision history.


#include <boost/config.hpp>  // for workarounds                                                                        
#if defined (BOOST_HAS_THREADS) && !defined(BOOST_POOL_NO_MT)                                                          
#if defined (BOOST_NO_CXX11_HDR_MUTEX)                                                                                 
#include <boost/thread/mutex.hpp>                                                                                      
#include <mutex>                                                                                                       

namespace boost{ namespace details{ namespace pool{

class null_mutex
    null_mutex(const null_mutex &);
    void operator=(const null_mutex &);

    null_mutex() { }

    static void lock() { }
    static void unlock() { }

#if !defined(BOOST_HAS_THREADS) || defined(BOOST_NO_MT) || defined(BOOST_POOL_NO_MT)                                   
  typedef null_mutex default_mutex;                                                                                    
#if defined (BOOST_NO_CXX11_HDR_MUTEX)                                                                                 
  typedef boost::mutex default_mutex;                                                                                  
  typedef std::mutex default_mutex;                                                                                    

} // namespace pool
} // namespace details
} // namespace boost