Use boost::empty_value

fix #1233

test/beast/core/CMakeLists.txt

@@ -45,7 +45,6 @@ add_executable (tests-beast-core
     type_traits.cpp
     detail/base64.cpp
     detail/clamp.cpp
-    detail/empty_base_optimization.cpp
     detail/sha1.cpp
     detail/variant.cpp
     detail/varint.cpp

test/beast/core/Jamfile

@@ -34,7 +34,6 @@ local SOURCES =
     type_traits.cpp
     detail/base64.cpp
     detail/clamp.cpp
-    detail/empty_base_optimization.cpp
     detail/sha1.cpp
     detail/variant.cpp
     detail/varint.cpp

test/beast/core/detail/empty_base_optimization.cpp

@@ -1,98 +0,0 @@
-//
-// Copyright (c) 2016-2017 Vinnie Falco (vinnie dot falco at gmail dot com)
-//
-// 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)
-//
-// Official repository: https://github.com/boostorg/beast
-//
-
-// Test that header file is self-contained.
-#include <boost/beast/core/detail/empty_base_optimization.hpp>
-
-#include <boost/beast/unit_test/suite.hpp>
-
-namespace boost {
-namespace beast {
-namespace detail {
-
-class empty_base_optimization_test
-    : public beast::unit_test::suite
-{
-public:
-    template<class T>
-    class test1
-        : private empty_base_optimization<T>
-    {
-        using Base = empty_base_optimization<T>;
-        void* m_p;
-    public:
-        explicit test1 (T const& t)
-            : Base (t)
-        {}
-
-        T&       member()       {return Base::member();}
-        T const& member() const {return Base::member();}
-    };
-
-    template<class T>
-    class test2
-    {
-        void* m_p;
-        T m_t;
-    public:
-        explicit test2 (T const& t)
-            : m_t (t)
-        {}
-
-        T&       member()       {return m_t;}
-        T const& member() const {return m_t;}
-    };
-
-    struct Empty
-    {
-        operator bool() {return true;}
-    };
-
-    static
-    bool
-    test_one()
-    {
-        test1<int> t1(1);
-        test2<int> t2(2);
-        static_assert(sizeof(t1) == sizeof(t2), "don't optimize for int");
-        if(t1.member() != 1)
-            return false;
-        if(t2.member() != 2)
-            return false;
-        return true;
-    }
-
-    static
-    bool
-    test_two()
-    {
-        test1<Empty> t1((Empty()));
-        test2<Empty> t2((Empty()));
-        static_assert(sizeof(t1) < sizeof(t2), "do optimize for Empty");
-        if(t1.member() != true)
-            return false;
-        if(t2.member() != true)
-            return false;
-        return true;
-    }
-
-    void
-    run()
-    {
-        BEAST_EXPECT(test_one());
-        BEAST_EXPECT(test_two());
-        pass();
-    }
-};
-
-BEAST_DEFINE_TESTSUITE(beast,core,empty_base_optimization);
-
-} // detail
-} // beast
-} // boost

test/beast/http/rfc7230.cpp

@@ -15,8 +15,6 @@
 #include <string>
 #include <vector>
 
-#include <boost/beast/core/detail/empty_base_optimization.hpp>
-
 namespace boost {
 namespace beast {
 namespace http {