diff --git a/include/boost/smart_ptr/detail/sp_counted_base_clang.hpp b/include/boost/smart_ptr/detail/sp_counted_base_clang.hpp
deleted file mode 100644
index 3a2ab0e..0000000
--- a/include/boost/smart_ptr/detail/sp_counted_base_clang.hpp
+++ /dev/null
@@ -1,168 +0,0 @@
-#ifndef BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_CLANG_HPP_INCLUDED
-#define BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_CLANG_HPP_INCLUDED
-
-// MS compatible compilers support #pragma once
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1020)
-# pragma once
-#endif
-
-//  detail/sp_counted_base_clang.hpp - __c11 clang intrinsics
-//
-//  Copyright (c) 2007, 2013, 2015 Peter Dimov
-//
-//  Distributed under the Boost Software License, Version 1.0.
-//  See accompanying file LICENSE_1_0.txt or copy at
-//  http://www.boost.org/LICENSE_1_0.txt
-
-#include <boost/smart_ptr/detail/sp_typeinfo_.hpp>
-#include <boost/smart_ptr/detail/sp_noexcept.hpp>
-#include <boost/config.hpp>
-#include <boost/cstdint.hpp>
-
-#if defined(BOOST_SP_REPORT_IMPLEMENTATION)
-
-#include <boost/config/pragma_message.hpp>
-BOOST_PRAGMA_MESSAGE("Using Clang/C11 sp_counted_base")
-
-#endif
-
-namespace boost
-{
-
-namespace detail
-{
-
-#if defined(__clang__)
-# pragma clang diagnostic push
-#endif
-
-#if defined(__clang__) && defined(__has_warning)
-# if __has_warning( "-Wc11-extensions" )
-#  pragma clang diagnostic ignored "-Wc11-extensions"
-# endif
-#endif
-
-typedef _Atomic( boost::int_least32_t ) atomic_int_least32_t;
-
-inline void atomic_increment( atomic_int_least32_t * pw ) BOOST_SP_NOEXCEPT
-{
-    __c11_atomic_fetch_add( pw, 1, __ATOMIC_RELAXED );
-}
-
-inline boost::int_least32_t atomic_decrement( atomic_int_least32_t * pw ) BOOST_SP_NOEXCEPT
-{
-    return __c11_atomic_fetch_sub( pw, 1, __ATOMIC_ACQ_REL );
-}
-
-inline boost::int_least32_t atomic_conditional_increment( atomic_int_least32_t * pw ) BOOST_SP_NOEXCEPT
-{
-    // long r = *pw;
-    // if( r != 0 ) ++*pw;
-    // return r;
-
-    boost::int_least32_t r = __c11_atomic_load( pw, __ATOMIC_RELAXED );
-
-    for( ;; )
-    {
-        if( r == 0 )
-        {
-            return r;
-        }
-
-        if( __c11_atomic_compare_exchange_weak( pw, &r, r + 1, __ATOMIC_RELAXED, __ATOMIC_RELAXED ) )
-        {
-            return r;
-        }
-    }    
-}
-
-#if defined(__clang__)
-# pragma clang diagnostic ignored "-Wweak-vtables"
-#endif
-
-class BOOST_SYMBOL_VISIBLE sp_counted_base
-{
-private:
-
-    sp_counted_base( sp_counted_base const & );
-    sp_counted_base & operator= ( sp_counted_base const & );
-
-    atomic_int_least32_t use_count_;    // #shared
-    atomic_int_least32_t weak_count_;   // #weak + (#shared != 0)
-
-public:
-
-    sp_counted_base() BOOST_SP_NOEXCEPT
-    {
-        __c11_atomic_init( &use_count_, 1 );
-        __c11_atomic_init( &weak_count_, 1 );
-    }
-
-    virtual ~sp_counted_base() /*BOOST_SP_NOEXCEPT*/
-    {
-    }
-
-    // dispose() is called when use_count_ drops to zero, to release
-    // the resources managed by *this.
-
-    virtual void dispose() BOOST_SP_NOEXCEPT = 0; // nothrow
-
-    // destroy() is called when weak_count_ drops to zero.
-
-    virtual void destroy() BOOST_SP_NOEXCEPT // nothrow
-    {
-        delete this;
-    }
-
-    virtual void * get_deleter( sp_typeinfo_ const & ti ) BOOST_SP_NOEXCEPT = 0;
-    virtual void * get_local_deleter( sp_typeinfo_ const & ti ) BOOST_SP_NOEXCEPT = 0;
-    virtual void * get_untyped_deleter() BOOST_SP_NOEXCEPT = 0;
-
-    void add_ref_copy() BOOST_SP_NOEXCEPT
-    {
-        atomic_increment( &use_count_ );
-    }
-
-    bool add_ref_lock() BOOST_SP_NOEXCEPT // true on success
-    {
-        return atomic_conditional_increment( &use_count_ ) != 0;
-    }
-
-    void release() BOOST_SP_NOEXCEPT
-    {
-        if( atomic_decrement( &use_count_ ) == 1 )
-        {
-            dispose();
-            weak_release();
-        }
-    }
-
-    void weak_add_ref() BOOST_SP_NOEXCEPT
-    {
-        atomic_increment( &weak_count_ );
-    }
-
-    void weak_release() BOOST_SP_NOEXCEPT
-    {
-        if( atomic_decrement( &weak_count_ ) == 1 )
-        {
-            destroy();
-        }
-    }
-
-    long use_count() const BOOST_SP_NOEXCEPT
-    {
-        return __c11_atomic_load( const_cast< atomic_int_least32_t* >( &use_count_ ), __ATOMIC_ACQUIRE );
-    }
-};
-
-#if defined(__clang__)
-# pragma clang diagnostic pop
-#endif
-
-} // namespace detail
-
-} // namespace boost
-
-#endif  // #ifndef BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_CLANG_HPP_INCLUDED