Make fusion::pair trivially copyable if possible

in order to reuse it in is_mpl_sequence

.travis.yml

@@ -1,5 +1,5 @@
 # Copyright 2016, 2017 Peter Dimov
-# Copyright 2017 Kohei Takahashi
+# Copyright 2017-2018 Kohei Takahashi
 # Distributed under the Boost Software License, Version 1.0.
 # (See accompanying file LICENSE_1_0.txt or copy at http://boost.org/LICENSE_1_0.txt)
 
@@ -167,6 +167,7 @@ install:
   - git submodule init libs/bind
   - git submodule init libs/concept_check
   - git submodule init libs/config
+  - git submodule init libs/container_hash
   - git submodule init libs/conversion
   - git submodule init libs/core
   - git submodule init libs/detail
@@ -201,4 +202,4 @@ install:
   - ./b2 headers
 
 script:
-  - ./b2 libs/fusion/test toolset=$TOOLSET cxxstd=$CXXSTD define=RUNNING_ON_TRAVIS=1
+  - ./b2 -j`(nproc || sysctl -n hw.ncpu) 2> /dev/null` libs/fusion/test toolset=$TOOLSET cxxstd=$CXXSTD

appveyor.yml

@@ -1,5 +1,5 @@
 # Copyright 2016, 2017 Peter Dimov
-# Copyright 2017 Kohei Takahashi
+# Copyright 2017-2018 Kohei Takahashi
 # Distributed under the Boost Software License, Version 1.0.
 # (See accompanying file LICENSE_1_0.txt or copy at http://boost.org/LICENSE_1_0.txt)
 
@@ -39,6 +39,7 @@ install:
   - git submodule init libs/bind
   - git submodule init libs/concept_check
   - git submodule init libs/config
+  - git submodule init libs/container_hash
   - git submodule init libs/conversion
   - git submodule init libs/core
   - git submodule init libs/detail
@@ -71,4 +72,4 @@ install:
 build: off
 
 test_script:
-  - b2 libs/fusion/test toolset=%TOOLSET% define=RUNNING_ON_APPVEYOR=1
+  - b2 -j%NUMBER_OF_PROCESSORS% --hash libs/fusion/test toolset=%TOOLSET%

doc/fusion.qbk

@@ -2,6 +2,7 @@
     Copyright (C) 2001-2011 Joel de Guzman
     Copyright (C) 2006 Dan Marsden
     Copyright (C) 2010 Christopher Schmidt
+    Copyright (C) 2018 Kohei Takahashi
 
     Use, modification and distribution is subject to the Boost Software
     License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
@@ -20,39 +21,37 @@
     ]
 ]
 
-[def __spirit__                 [@http://spirit.sourceforge.net Spirit]]
-[def __phoenix__                [@http://www.boost.org/libs/phoenix/index.html Phoenix]]
-[def __mpl__                    [@http://www.boost.org/libs/mpl/index.html MPL]]
+[def __spirit__                 [@http://boost-spirit.com/home/ Spirit]]
+[def __phoenix__                [@http://www.boost.org/libs/phoenix Phoenix]]
+[def __mpl__                    [@http://www.boost.org/libs/mpl MPL]]
 [def __stl__                    [@http://en.wikipedia.org/wiki/Standard_Template_Library STL]]
-[def __tuple__                  [@http://www.boost.org/libs/tuple/doc/tuple_users_guide.html Boost.Tuple]]
+[def __tuple__                  [@http://www.boost.org/libs/tuple Boost.Tuple]]
 [def __tr1__tuple__             [@http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2002/n1403.pdf TR1 Tuple]]
 [def __boost_tools__            [@http://www.boost.org/tools/index.html Boost Tools]]
-[def __spirit_list__            [@https://lists.sourceforge.net/lists/listinfo/spirit-general Spirit Mailing List]]
-[def __spirit_general__         [@news://news.gmane.org/gmane.comp.spirit.general Spirit General NNTP news portal]]
-[def __gmane__                  [@http://www.gmane.org Gmane]]
-[def __mlist_archive__          [@http://news.gmane.org/gmane.comp.parsers.spirit.general]]
+[def __spirit_list__            [@https://sourceforge.net/projects/spirit/lists/spirit-general Spirit Mailing List]]
+[def __list_archive__           [@https://sourceforge.net/p/spirit/mailman/spirit-general/ archive]]
 [def __jaakko_jarvi__           [@http://www.boost.org/people/jaakko_jarvi.htm Jaakko Jarvi]]
 [def __david_abrahams__         [@http://www.boost.org/people/dave_abrahams.htm David Abrahams]]
 [def __the_forwarding_problem__ [@http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2002/n1385.htm The Forwarding Problem]]
 
-[def __boost_any__              [@http://www.boost.org/doc/html/any.html Boost.Any]]
+[def __boost_any__              [@http://www.boost.org/libs/any Boost.Any Library]]
 [def __new_iterator_concepts__  [@http://www.boost.org/libs/iterator/doc/new-iter-concepts.html New Iterator Concepts]]
-[def __boost_array_library__    [@http://www.boost.org/doc/html/array.html Boost.Array Library]]
-[def __boost_variant_library__  [@http://www.boost.org/doc/html/variant.html Boost.Variant Library]]
-[def __boost_tuple_library__    [@http://www.boost.org/libs/tuple/doc/tuple_users_guide.html Boost.Tuple Library]]
-[def __boost_ref__              [@http://www.boost.org/doc/html/ref.html Boost.Ref]]
-[def __boost_ref_call__         [@http://www.boost.org/doc/html/ref.html `ref`]]
-[def __boost_result_of__        [@http://www.boost.org/libs/utility/utility.htm#result_of Boost.ResultOf]]
+[def __boost_array_library__    [@http://www.boost.org/libs/array Boost.Array Library]]
+[def __boost_variant_library__  [@http://www.boost.org/libs/variant Boost.Variant Library]]
+[def __boost_tuple_library__    [@http://www.boost.org/libs/tuple Boost.Tuple Library]]
+[def __boost_ref__              [@http://www.boost.org/libs/core/ref.html Ref utility]]
+[def __boost_ref_call__         [@http://www.boost.org/libs/core/ref.html `ref`]]
+[def __boost_result_of__        [@http://www.boost.org/libs/utility/utility.htm#result_of ResultOf utility]]
 [def __boost_result_of_call__   [@http://www.boost.org/libs/utility/utility.htm#result_of `boost::result_of`]]
-[def __boost_enable_if__        [@http://www.boost.org/libs/utility/enable_if.html Boost.EnableIf utility]]
-[def __boost_shared_ptr_call__  [@http://www.boost.org/libs/smart_ptr/shared_ptr.htm `boost::shared_ptr`]]
-[def __boost_func_forward__     [@http://www.boost.org/libs/functional/forward/doc/html/index.html Boost.Functional/Forward]]
-[def __boost_func_factory__     [@http://www.boost.org/libs/functional/factory/doc/html/index.html Boost.Functional/Factory]]
-[def __boost_func_hash__        [@http://www.boost.org/doc/html/hash.html Boost.Functional/Hash]]
-[def __std_pair_doc__           [@http://www.sgi.com/tech/stl/pair.html `std::pair`]]
+[def __boost_enable_if__        [@http://www.boost.org/libs/core/doc/html/core/enable_if.html EnableIf utility]]
+[def __boost_shared_ptr_call__  [@http://www.boost.org/libs/smart_ptr#shared_ptr `boost::shared_ptr`]]
+[def __boost_func_forward__     [@http://www.boost.org/libs/functional/forward Boost.Functional/Forward Library]]
+[def __boost_func_factory__     [@http://www.boost.org/libs/functional/factory Boost.Functional/Factory Library]]
+[def __boost_func_hash__        [@http://www.boost.org/doc/html/hash.html Boost.ContainerHash Library]]
+[def __std_pair_doc__           [@http://en.cppreference.com/w/cpp/utility/pair `std::pair`]]
 [def __std_tuple_doc__          [@http://en.cppreference.com/w/cpp/utility/tuple `std::tuple`]]
-[def __std_plus_doc__           [@http://www.sgi.com/tech/stl/plus.html `std::plus`]]
-[def __std_minus_doc__          [@http://www.sgi.com/tech/stl/minus.html `std::minus`]]
+[def __std_plus_doc__           [@http://en.cppreference.com/w/cpp/utility/functional/plus `std::plus`]]
+[def __std_minus_doc__          [@http://en.cppreference.com/w/cpp/utility/functional/minus `std::minus`]]
 
 [def __mpl_integral_constant__  [@http://www.boost.org/libs/mpl/doc/refmanual/integral-constant.html MPL Integral Constant]]
 [def __mpl_boolean_constant__   [@http://www.boost.org/libs/mpl/doc/refmanual/integral-constant.html MPL Boolean Constant]]

doc/preface.qbk

@@ -61,11 +61,8 @@ tool. QuickBook can be found in the __boost_tools__.
 [heading Support]
 
 Please direct all questions to Spirit's mailing list. You can subscribe to the
-__spirit_list__. The mailing list has a searchable archive. A search link to
-this archive is provided in __spirit__'s home page. You may also read and post
-messages to the mailing list through __spirit_general__ (thanks to __gmane__).
-The news group mirrors the mailing list. Here is a link to the archives:
-__mlist_archive__.
+__spirit_list__. The mailing list has a searchable archive. Here is a link to
+the archives: __list_archive__.
 
 [endsect]
 

doc/references.qbk

@@ -1,6 +1,7 @@
 [/==============================================================================
     Copyright (C) 2001-2011 Joel de Guzman
     Copyright (C) 2006 Dan Marsden
+    Copyright (C) 2018 Kohei Takahashi
 
     Use, modification and distribution is subject to the Boost Software
     License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
@@ -8,20 +9,20 @@
 ===============================================================================/]
 [section References]
 
-# [@http://boost.org/libs/iterator/doc/new-iter-concepts.html New Iterator Concepts],
+# [@http://www.boost.org/libs/iterator/doc/new-iter-concepts.html New Iterator Concepts],
   David Abrahams, Jeremy Siek, Thomas Witt, 2004-11-01.
-# [@http://boost.org/libs/tuple/doc/tuple_users_guide.html The Boost Tuple Library],
+# [@http://www.boost.org/libs/tuple The Boost Tuple Library],
   Jaakko Jarvi, 2001.
-# [@http://www.boost.org/libs/spirit/ Spirit Parser Library],
+# [@http://www.boost.org/libs/spirit Spirit Parser Library],
   Joel de Guzman, 2001-2006.
-# [@http://www.boost.org/libs/mpl/ The Boost MPL Library],
+# [@http://www.boost.org/libs/mpl The Boost MPL Library],
   Aleksey Gurtovoy and David Abrahams, 2002-2004.
-# [@http://www.boost.org/doc/html/array.html Boost Array],
+# [@http://www.boost.org/libs/array The Boost Array Library],
   Nicolai Josuttis, 2002-2004.
-# [@http://www.sgi.com/tech/stl/ Standard Template Library Programmer's Guide],
-  Hewlett-Packard Company, 1994.
-# [@http://www.boost.org/doc/html/ref.html Boost.Ref],
+# [@http://www.boost.org/libs/core/ref.html Boost.Core / Ref utility],
   Jaakko Jarvi, Peter Dimov, Douglas Gregor, Dave Abrahams, 1999-2002.
+# [@http://www.boost.org/libs/hana The Boost Hana Library],
+  Louis Dionne, 2017.
 
 [endsect]
 

include/boost/fusion/container/deque/detail/cpp03/as_deque.hpp

@@ -26,7 +26,13 @@ namespace boost { namespace fusion { namespace detail
 BOOST_FUSION_BARRIER_BEGIN
 
     template <int size>
-    struct as_deque;
+    struct as_deque
+    {
+        BOOST_STATIC_ASSERT_MSG(
+            size <= FUSION_MAX_DEQUE_SIZE
+          , "FUSION_MAX_DEQUE_SIZE limit is too low"
+        );
+    };
 
     template <>
     struct as_deque<0>

include/boost/fusion/container/map/detail/cpp03/as_map.hpp

@@ -25,7 +25,13 @@ namespace boost { namespace fusion { namespace detail
 BOOST_FUSION_BARRIER_BEGIN
 
     template <int size, bool is_assoc>
-    struct as_map;
+    struct as_map
+    {
+        BOOST_STATIC_ASSERT_MSG(
+            size <= FUSION_MAX_MAP_SIZE
+          , "FUSION_MAX_MAP_SIZE limit is too low"
+        );
+    };
 
     template <bool is_assoc>
     struct as_map<0, is_assoc>

include/boost/fusion/container/map/map.hpp

@@ -67,24 +67,21 @@ namespace boost { namespace fusion
           : base_type(std::forward<map>(seq))
         {}
 
-        template <typename Sequence>
+        template <typename Sequence, typename = typename enable_if<traits::is_sequence<Sequence>>::type>
         BOOST_FUSION_GPU_ENABLED
-        map(Sequence const& seq
-          , typename enable_if<traits::is_sequence<Sequence>, detail::enabler_>::type = detail::enabler)
+        map(Sequence const& seq)
           : base_type(begin(seq), detail::map_impl_from_iterator())
         {}
 
-        template <typename Sequence>
+        template <typename Sequence, typename = typename enable_if<traits::is_sequence<Sequence>>::type>
         BOOST_FUSION_GPU_ENABLED
-        map(Sequence& seq
-          , typename enable_if<traits::is_sequence<Sequence>, detail::enabler_>::type = detail::enabler)
+        map(Sequence& seq)
           : base_type(begin(seq), detail::map_impl_from_iterator())
         {}
 
-        template <typename Sequence>
+        template <typename Sequence, typename = typename enable_if<traits::is_sequence<Sequence>>::type>
         BOOST_FUSION_GPU_ENABLED
-        map(Sequence&& seq
-          , typename enable_if<traits::is_sequence<Sequence>, detail::enabler_>::type = detail::enabler)
+        map(Sequence&& seq)
           : base_type(begin(seq), detail::map_impl_from_iterator())
         {}
 

include/boost/fusion/container/set/detail/cpp03/as_set.hpp

@@ -25,7 +25,13 @@ namespace boost { namespace fusion { namespace detail
 BOOST_FUSION_BARRIER_BEGIN
 
     template <int size>
-    struct as_set;
+    struct as_set
+    {
+        BOOST_STATIC_ASSERT_MSG(
+            size <= FUSION_MAX_SET_SIZE
+          , "FUSION_MAX_SET_SIZE limit is too low"
+        );
+    };
 
     template <>
     struct as_set<0>

include/boost/fusion/container/vector/detail/cpp03/as_vector.hpp

@@ -25,7 +25,13 @@ namespace boost { namespace fusion { namespace detail
 BOOST_FUSION_BARRIER_BEGIN
 
     template <int size>
-    struct as_vector;
+    struct as_vector
+    {
+        BOOST_STATIC_ASSERT_MSG(
+            size <= FUSION_MAX_VECTOR_SIZE
+          , "FUSION_MAX_VECTOR_SIZE limit is too low"
+        );
+    };
 
     template <>
     struct as_vector<0>

include/boost/fusion/container/vector/vector.hpp

@@ -247,14 +247,14 @@ namespace boost { namespace fusion
 
             template <typename J>
             BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
-            auto at_impl(J) -> decltype(at_detail<J::value>(this))
+            auto at_impl(J) -> decltype(at_detail<J::value>(&std::declval<vector_data&>()))
             {
                 return at_detail<J::value>(this);
             }
 
             template <typename J>
             BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
-            auto at_impl(J) const -> decltype(at_detail<J::value>(this))
+            auto at_impl(J) const -> decltype(at_detail<J::value>(&std::declval<vector_data const&>()))
             {
                 return at_detail<J::value>(this);
             }

include/boost/fusion/support/category_of.hpp

@@ -8,7 +8,6 @@
 #define FUSION_CATEGORY_OF_07202005_0308
 
 #include <boost/fusion/support/config.hpp>
-#include <boost/fusion/support/detail/category_of.hpp>
 #include <boost/fusion/support/tag_of.hpp>
 #include <boost/type_traits/is_base_of.hpp>
 
@@ -44,7 +43,10 @@ namespace boost { namespace fusion
         struct category_of_impl
         {
             template<typename T>
-            struct apply : detail::fusion_category_of<T> {};
+            struct apply
+            {
+                typedef typename T::category type;
+            };
         };
 
         template <>

include/boost/fusion/support/detail/and.hpp

@@ -15,6 +15,7 @@
 #endif
 
 namespace boost { namespace fusion { namespace detail {
+#if defined(BOOST_NO_CXX17_FOLD_EXPRESSIONS)
     template<typename ...Cond>
     struct and_impl : false_type {};
 
@@ -34,6 +35,10 @@ namespace boost { namespace fusion { namespace detail {
          recursive. */
     template<typename ...Cond>
     struct and_ : and_impl1<Cond::value...> {};
+#else
+    template <typename ...Cond>
+    struct and_ : integral_constant<bool, ((bool)Cond::value && ...)> {};
+#endif
 }}}
 
 #endif // FUSION_AND_07152016_1625

include/boost/fusion/support/detail/category_of.hpp

@@ -1,19 +0,0 @@
-/*=============================================================================
-    Copyright (c) 2001-2011 Joel de Guzman
-
-    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)
-==============================================================================*/
-#if !defined(FUSION_CATEGORY_OF_07212005_1025)
-#define FUSION_CATEGORY_OF_07212005_1025
-
-namespace boost { namespace fusion { namespace detail
-{
-    template <typename T>
-    struct fusion_category_of
-    {
-        typedef typename T::category type;
-    };
-}}}
-
-#endif

include/boost/fusion/support/detail/is_mpl_sequence.hpp

@@ -9,18 +9,17 @@
 #define FUSION_DETAIL_IS_MPL_SEQUENCE_29122006_1105
 
 #include <boost/fusion/support/config.hpp>
-#include <boost/fusion/support/sequence_base.hpp>
+#include <boost/fusion/support/detail/is_native_fusion_sequence.hpp>
 #include <boost/mpl/is_sequence.hpp>
 #include <boost/mpl/and.hpp>
 #include <boost/mpl/not.hpp>
-#include <boost/type_traits/is_convertible.hpp>
 
 namespace boost { namespace fusion { namespace detail
 {
     template <typename T>
     struct is_mpl_sequence
         : mpl::and_<
-            mpl::not_<is_convertible<T, from_sequence_convertible_type> >
+            mpl::not_<is_native_fusion_sequence<T> >
           , mpl::is_sequence<T> >
     {};
 }}}

include/boost/fusion/support/detail/is_native_fusion_sequence.hpp

@@ -0,0 +1,27 @@
+/*=============================================================================
+    Copyright (c) 2018 Kohei Takahashi
+
+    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)
+==============================================================================*/
+#ifndef BOOST_FUSION_IS_NATIVE_FUSION_SEQUENCE
+#define BOOST_FUSION_IS_NATIVE_FUSION_SEQUENCE
+
+#include <boost/fusion/support/config.hpp>
+#include <boost/fusion/support/sequence_base.hpp>
+#include <boost/mpl/and.hpp>
+#include <boost/type_traits/is_complete.hpp>
+#include <boost/type_traits/is_convertible.hpp>
+
+namespace boost { namespace fusion { namespace detail
+{
+    template <typename Sequence>
+    struct is_native_fusion_sequence
+      : mpl::and_<
+          is_complete<Sequence>
+        , is_convertible<Sequence, detail::from_sequence_convertible_type>
+      >
+    {};
+}}}
+
+#endif

include/boost/fusion/support/detail/is_view.hpp

@@ -1,19 +0,0 @@
-/*=============================================================================
-    Copyright (c) 2001-2011 Joel de Guzman
-
-    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)
-==============================================================================*/
-#if !defined(FUSION_IS_VIEW_03202006_0018)
-#define FUSION_IS_VIEW_03202006_0018
-
-namespace boost { namespace fusion { namespace detail
-{
-    template <typename T>
-    struct fusion_is_view
-    {
-        typedef typename T::is_view type;
-    };
-}}}
-
-#endif

include/boost/fusion/support/detail/unknown_key.hpp

@@ -1,16 +0,0 @@
-/*=============================================================================
-    Copyright (c) 2001-2011 Joel de Guzman
-
-    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)
-==============================================================================*/
-#if !defined(FUSION_UNKNOWN_KEY_09242005_1219)
-#define FUSION_UNKNOWN_KEY_09242005_1219
-
-namespace boost { namespace fusion { namespace detail
-{
-    template <int index>
-    struct unknown_key {};
-}}}
-
-#endif

include/boost/fusion/support/is_sequence.hpp

@@ -10,11 +10,10 @@
 #include <boost/fusion/support/config.hpp>
 #include <boost/fusion/support/sequence_base.hpp>
 #include <boost/fusion/support/tag_of.hpp>
-#include <boost/mpl/is_sequence.hpp>
-#include <boost/mpl/or.hpp>
+#include <boost/fusion/support/detail/is_native_fusion_sequence.hpp>
 #include <boost/mpl/bool.hpp>
+#include <boost/mpl/is_sequence.hpp>
 #include <boost/type_traits/is_convertible.hpp>
-#include <boost/type_traits/is_same.hpp>
 
 namespace boost { namespace fusion
 {
@@ -67,10 +66,7 @@ namespace boost { namespace fusion
             >
         {};
 
-        template <typename Sequence, typename Enable = void>
-        struct is_native_fusion_sequence
-          : is_convertible<Sequence, fusion::detail::from_sequence_convertible_type>
-        {};
+        using detail::is_native_fusion_sequence;
     }
 }}
 

include/boost/fusion/support/is_view.hpp

@@ -9,7 +9,6 @@
 
 #include <boost/fusion/support/config.hpp>
 #include <boost/mpl/bool.hpp>
-#include <boost/fusion/support/detail/is_view.hpp>
 #include <boost/fusion/support/tag_of.hpp>
 
 namespace boost { namespace fusion
@@ -28,8 +27,9 @@ namespace boost { namespace fusion
         {
             template <typename T>
             struct apply
-                : detail::fusion_is_view<T>
-            {};
+            {
+                typedef typename T::is_view type;
+            };
         };
 
         template <>

include/boost/fusion/support/pair.hpp

@@ -8,15 +8,16 @@
 #if !defined(FUSION_PAIR_07222005_1203)
 #define FUSION_PAIR_07222005_1203
 
-#include <boost/fusion/support/config.hpp>
 #include <iosfwd>
-
+#include <utility>
+#include <boost/fusion/support/config.hpp>
 #include <boost/fusion/support/detail/access.hpp>
 #include <boost/fusion/support/detail/as_fusion_element.hpp>
-#include <boost/config.hpp>
-#include <boost/utility/enable_if.hpp>
+#include <boost/fusion/support/detail/enabler.hpp>
+#include <boost/core/enable_if.hpp>
+#include <boost/type_traits/is_same.hpp>
 #include <boost/type_traits/is_convertible.hpp>
-#include <boost/type_traits/is_lvalue_reference.hpp>
+#include <boost/type_traits/remove_cv_ref.hpp>
 
 #if defined (BOOST_MSVC)
 #  pragma warning(push)
@@ -33,54 +34,46 @@ namespace boost { namespace fusion
         pair()
             : second() {}
 
-        BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
-        pair(pair const& rhs)
-            : second(rhs.second) {}
-
-#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
-        BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
-        pair(pair&& rhs)
-            : second(BOOST_FUSION_FWD_ELEM(Second, rhs.second)) {}
-#endif
-
         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
         pair(typename detail::call_param<Second>::type val)
             : second(val) {}
 
 #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
-        template <typename Second2>
         BOOST_FUSION_GPU_ENABLED
-        pair(Second2&& val
-          , typename boost::disable_if<is_lvalue_reference<Second2> >::type* /* dummy */ = 0
-          , typename boost::enable_if<is_convertible<Second2, Second> >::type* /*dummy*/ = 0
-        ) : second(BOOST_FUSION_FWD_ELEM(Second, val)) {}
+        pair(typename remove_cv_ref<Second>::type&& val)
+            : second(BOOST_FUSION_FWD_ELEM(Second, val)) {}
 #endif
 
         template <typename Second2>
         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
-        pair(pair<First, Second2> const& rhs)
+        pair(pair<First, Second2> const& rhs,
+             typename disable_if<is_same<Second, Second2>, detail::enabler_>::type = detail::enabler,
+             typename enable_if<is_convertible<Second2, Second>, detail::enabler_>::type = detail::enabler)
             : second(rhs.second) {}
 
         template <typename Second2>
         BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
-        pair& operator=(pair<First, Second2> const& rhs)
-        {
-            second = rhs.second;
-            return *this;
-        }
-
-        BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
-        pair& operator=(pair const& rhs)
+        typename disable_if<is_same<Second, Second2>, pair&>::type
+        operator=(pair<First, Second2> const& rhs)
         {
             second = rhs.second;
             return *this;
         }
 
 #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
+        template <typename Second2>
+        BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
+        pair(pair<First, Second2>&& rhs,
+             typename disable_if<is_same<Second, Second2>, detail::enabler_>::type = detail::enabler,
+             typename enable_if<is_convertible<Second2, Second>, detail::enabler_>::type = detail::enabler)
+            : second(std::move(rhs.second)) {}
+
+        template <typename Second2>
         BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
-        pair& operator=(pair&& rhs)
+        typename disable_if<is_same<Second, Second2>, pair&>::type
+        operator=(pair<First, Second2>&& rhs)
         {
-            second = BOOST_FUSION_FWD_ELEM(Second, rhs.second);
+            second = std::move(rhs.second);
             return *this;
         }
 #endif

test/Jamfile

@@ -1,7 +1,7 @@
 ##==============================================================================
 #    Copyright (c) 2003-2006 Joel de Guzman
 #    Copyright (c) 2013 Mateusz Loskot
-#    Copyright (c) 2014-2017 Kohei Takahashi
+#    Copyright (c) 2014-2018 Kohei Takahashi
 #
 #   Use, modification and distribution is subject to the Boost Software
 #   License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
@@ -9,10 +9,17 @@
 #==============================================================================
 # bring in rules for testing
 import testing ;
+import os ;
 import ../../config/checks/config : requires ;
 
+if [ os.environ CI ]
+{
+    CI_DEFINES = <define>CI_SKIP_KNOWN_FAILURE=1 ;
+}
+
 project
     : requirements
+        $(CI_DEFINES)
     ;
 
 {
@@ -35,7 +42,8 @@ project
     [ run algorithm/insert.cpp ]
     [ run algorithm/insert_range.cpp ]
     [ run algorithm/iter_fold.cpp ]
-    [ run algorithm/move.cpp ]
+    [ run algorithm/move.cpp : :
+        : [ requires cxx11_rvalue_references ] ]
     [ run algorithm/none.cpp ]
     [ run algorithm/pop_back.cpp ]
     [ run algorithm/pop_front.cpp ]
@@ -99,7 +107,8 @@ project
     [ compile sequence/deque_is_constructible.cpp ]
     [ run sequence/deque_make.cpp ]
     [ run sequence/deque_misc.cpp ]
-    [ run sequence/deque_move.cpp ]
+    [ run sequence/deque_move.cpp : :
+        : [ requires cxx11_rvalue_references ] ]
     [ run sequence/deque_mutate.cpp ]
     [ run sequence/deque_nest.cpp ]
     [ run sequence/deque_tie.cpp ]
@@ -113,7 +122,8 @@ project
     [ run sequence/map_construction.cpp ]
     [ run sequence/map_copy.cpp ]
     [ run sequence/map_misc.cpp ]
-    [ run sequence/map_move.cpp ]
+    [ run sequence/map_move.cpp : :
+        : [ requires cxx11_rvalue_references ] ]
     [ run sequence/map_mutate.cpp ]
     [ run sequence/map_tie.cpp ]
     [ run sequence/nil.cpp ]
@@ -152,7 +162,8 @@ project
     [ run sequence/vector_iterator.cpp ]
     [ run sequence/vector_make.cpp ]
     [ run sequence/vector_misc.cpp ]
-    [ run sequence/vector_move.cpp ]
+    [ run sequence/vector_move.cpp : :
+        : [ requires cxx11_rvalue_references ] ]
     [ run sequence/vector_mutate.cpp ]
     [ run sequence/vector_n.cpp ]
     [ run sequence/vector_nest.cpp ]
@@ -197,22 +208,28 @@ project
     [ run sequence/adt_attribute_proxy.cpp ]
     [ run sequence/define_struct.cpp ]
     [ run sequence/define_struct_empty.cpp ]
-    [ run sequence/define_struct_move.cpp ]
+    [ run sequence/define_struct_move.cpp : :
+        : [ requires cxx11_rvalue_references ] ]
     [ run sequence/define_struct_inline.cpp ]
     [ run sequence/define_struct_inline_empty.cpp ]
-    [ run sequence/define_struct_inline_move.cpp ]
+    [ run sequence/define_struct_inline_move.cpp : :
+        : [ requires cxx11_rvalue_references ] ]
     [ run sequence/define_assoc_struct.cpp ]
     [ run sequence/define_assoc_struct_empty.cpp ]
-    [ run sequence/define_assoc_struct_move.cpp ]
+    [ run sequence/define_assoc_struct_move.cpp : :
+        : [ requires cxx11_rvalue_references ] ]
     [ run sequence/define_tpl_struct.cpp ]
     [ run sequence/define_tpl_struct_empty.cpp ]
-    [ run sequence/define_tpl_struct_move.cpp ]
+    [ run sequence/define_tpl_struct_move.cpp : :
+        : [ requires cxx11_rvalue_references ] ]
     [ run sequence/define_tpl_struct_inline.cpp ]
     [ run sequence/define_tpl_struct_inline_empty.cpp ]
-    [ run sequence/define_tpl_struct_inline_move.cpp ]
+    [ run sequence/define_tpl_struct_inline_move.cpp : :
+        : [ requires cxx11_rvalue_references ] ]
     [ run sequence/define_assoc_tpl_struct.cpp ]
     [ run sequence/define_assoc_tpl_struct_empty.cpp ]
-    [ run sequence/define_assoc_tpl_struct_move.cpp ]
+    [ run sequence/define_assoc_tpl_struct_move.cpp : :
+        : [ requires cxx11_rvalue_references ] ]
     [ run sequence/std_tuple.cpp : :
         : [ requires cxx11_variadic_templates cxx11_hdr_tuple ] ]
     [ run sequence/std_tuple_iterator.cpp : :
@@ -237,14 +254,21 @@ project
     [ run functional/invoke_procedure.cpp ]
     [ run sequence/swap.cpp ]
 
+    [ compile support/is_sequence.cpp ]
+    [ compile support/pair_conversion.cpp ]
     [ compile support/pair_deque.cpp ]
     [ compile support/pair_list.cpp ]
     [ compile support/pair_map.cpp ]
     [ compile support/pair_set.cpp ]
     [ compile support/pair_vector.cpp ]
     [ compile support/pair_nest.cpp ]
-    [ compile support/index_sequence.cpp ]
-    [ compile support/and.cpp ]
+    [ compile support/index_sequence.cpp
+        : [ requires cxx11_variadic_templates ] ]
+    [ compile support/and.cpp
+        : [ requires cxx11_variadic_templates ] ]
+    [ compile support/tag_of.cpp ]
+    [ compile support/pair_trivially_copyable.cpp
+        : [ requires cxx11_hdr_type_traits ] ]
 
 #   [ compile-fail xxx.cpp  ]
 

test/algorithm/move.cpp

@@ -1,13 +1,9 @@
 /*=============================================================================
-    Copyright (c) 2014 Kohei Takahashi
+    Copyright (c) 2014,2018 Kohei Takahashi
 
     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/config.hpp>
-
-#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
-
 #include <boost/core/lightweight_test.hpp>
 #include <boost/fusion/container/vector/vector.hpp>
 #include <boost/fusion/container/list/list.hpp>
@@ -29,12 +25,3 @@ int main()
     return boost::report_errors();
 }
 
-#else
-
-int main()
-{
-    // no thing to do
-}
-
-#endif
-

test/sequence/define_assoc_struct_move.cpp

@@ -1,13 +1,9 @@
 /*=============================================================================
-    Copyright (c) 2016 Kohei Takahashi
+    Copyright (c) 2016,2018 Kohei Takahashi
 
     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/config.hpp>
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
-
 #include <boost/detail/lightweight_test.hpp>
 #include <boost/fusion/adapted/struct/define_assoc_struct.hpp>
 #include <utility>
@@ -69,10 +65,3 @@ int main()
     return boost::report_errors();
 }
 
-#else
-
-int main()
-{
-}
-
-#endif

test/sequence/define_struct_inline_move.cpp

@@ -1,13 +1,9 @@
 /*=============================================================================
-    Copyright (c) 2016 Kohei Takahashi
+    Copyright (c) 2016-2018 Kohei Takahashi
 
     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/config.hpp>
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
-
 #include <boost/detail/lightweight_test.hpp>
 #include <boost/fusion/adapted/struct/define_struct_inline.hpp>
 #include <utility>
@@ -52,7 +48,7 @@ int main()
     }
 
     // Older MSVCs don't generate move ctor by default.
-#if !(defined(RUNNING_ON_APPVEYOR) && BOOST_WORKAROUND(BOOST_MSVC, < 1900))
+#if !(defined(CI_SKIP_KNOWN_FAILURE) && BOOST_WORKAROUND(BOOST_MSVC, < 1900))
     {
         ns::value x;
         ns::value y(std::move(x)); // move
@@ -70,15 +66,8 @@ int main()
         BOOST_TEST(x.w.value == 0);
         BOOST_TEST(y.w.value == 0);
     }
-#endif // !(appveyor && msvc < 14.0)
+#endif // !(ci && msvc < 14.0)
 
     return boost::report_errors();
 }
 
-#else
-
-int main()
-{
-}
-
-#endif

test/sequence/define_struct_move.cpp

@@ -1,13 +1,9 @@
 /*=============================================================================
-    Copyright (c) 2016 Kohei Takahashi
+    Copyright (c) 2016,2018 Kohei Takahashi
 
     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/config.hpp>
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
-
 #include <boost/detail/lightweight_test.hpp>
 #include <boost/fusion/adapted/struct/define_struct.hpp>
 #include <utility>
@@ -68,10 +64,3 @@ int main()
     return boost::report_errors();
 }
 
-#else
-
-int main()
-{
-}
-
-#endif

test/sequence/define_tpl_struct_inline_move.cpp

@@ -1,13 +1,9 @@
 /*=============================================================================
-    Copyright (c) 2016 Kohei Takahashi
+    Copyright (c) 2016-2018 Kohei Takahashi
 
     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/config.hpp>
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
-
 #include <boost/detail/lightweight_test.hpp>
 #include <boost/fusion/adapted/struct/define_struct_inline.hpp>
 #include <utility>
@@ -52,7 +48,7 @@ int main()
     }
 
     // Older MSVCs don't generate move ctor by default.
-#if !(defined(RUNNING_ON_APPVEYOR) && BOOST_WORKAROUND(BOOST_MSVC, < 1900))
+#if !(defined(CI_SKIP_KNOWN_FAILURE) && BOOST_WORKAROUND(BOOST_MSVC, < 1900))
     {
         ns::value<wrapper> x;
         ns::value<wrapper> y(std::move(x)); // move
@@ -70,15 +66,8 @@ int main()
         BOOST_TEST(x.w.value == 0);
         BOOST_TEST(y.w.value == 0);
     }
-#endif // !(appveyor && msvc < 14.0)
+#endif // !(ci && msvc < 14.0)
 
     return boost::report_errors();
 }
 
-#else
-
-int main()
-{
-}
-
-#endif

test/sequence/define_tpl_struct_move.cpp

@@ -1,13 +1,9 @@
 /*=============================================================================
-    Copyright (c) 2016 Kohei Takahashi
+    Copyright (c) 2016,2018 Kohei Takahashi
 
     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/config.hpp>
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
-
 #include <boost/detail/lightweight_test.hpp>
 #include <boost/fusion/adapted/struct/define_struct.hpp>
 #include <utility>
@@ -68,10 +64,3 @@ int main()
     return boost::report_errors();
 }
 
-#else
-
-int main()
-{
-}
-
-#endif

test/sequence/deque_move.cpp

@@ -1,16 +1,11 @@
 /*=============================================================================
     Copyright (c) 2012 Joel de Guzman
+    Copyright (c) 2018 Kohei Takahashi
 
     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)
 ==============================================================================*/
-#define BOOST_FUSION_DONT_USE_PREPROCESSED_FILES // $$$ JDG temp $$$
-
-
-#include <boost/config.hpp>
-
-#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
-
+#define BOOST_FUSION_DONT_USE_PREPROCESSED_FILES
 #include <boost/fusion/container/deque/deque.hpp>
 
 #define FUSION_SEQUENCE boost::fusion::deque<std::vector<x>>
@@ -18,16 +13,9 @@
 
 #include "move.hpp"
 
-#else
-#include <boost/detail/lightweight_test.hpp>
-#endif
-
-int
-main()
+int main()
 {
-#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
     test();
-#endif
 
     return boost::report_errors();
 }

test/sequence/map_move.cpp

@@ -1,15 +1,11 @@
 /*=============================================================================
     Copyright (c) 2012 Joel de Guzman
+    Copyright (c) 2018 Kohei Takahashi
 
     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)
 ==============================================================================*/
-#define BOOST_FUSION_DONT_USE_PREPROCESSED_FILES // $$$ JDG temp $$$
-
-#include <boost/config.hpp>
-
-#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
-
+#define BOOST_FUSION_DONT_USE_PREPROCESSED_FILES
 #include <boost/fusion/container/map/map.hpp>
 
 struct k1 {};
@@ -23,16 +19,9 @@ struct k2 {};
 
 #include "move.hpp"
 
-#else
-#include <boost/detail/lightweight_test.hpp>
-#endif
-
-int
-main()
+int main()
 {
-#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
     test();
-#endif
 
     return boost::report_errors();
 }

test/sequence/vector_move.cpp

@@ -1,15 +1,11 @@
 /*=============================================================================
     Copyright (c) 2012 Joel de Guzman
+    Copyright (c) 2018 Kohei Takahashi
 
     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)
 ==============================================================================*/
-#define BOOST_FUSION_DONT_USE_PREPROCESSED_FILES // $$$ JDG temp $$$
-
-#include <boost/config.hpp>
-
-#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
-
+#define BOOST_FUSION_DONT_USE_PREPROCESSED_FILES
 #include <boost/fusion/container/vector/vector.hpp>
 
 #define FUSION_SEQUENCE boost::fusion::vector<std::vector<x>>
@@ -17,16 +13,9 @@
 
 #include "move.hpp"
 
-#else
-#include <boost/detail/lightweight_test.hpp>
-#endif
-
-int
-main()
+int main()
 {
-#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
     test();
-#endif
 
     return boost::report_errors();
 }

test/support/and.cpp

@@ -1,33 +1,28 @@
 /*=============================================================================
     Copyright (c) 2016 Lee Clagett
+    Copyright (c) 2018 Kohei Takahashi
     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/config.hpp>
 
-#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
-
-#include <boost/detail/lightweight_test.hpp>
-#include <boost/fusion/support/detail/and.hpp>
-#include <boost/mpl/bool.hpp>
-#include <boost/type_traits/integral_constant.hpp>
-
-int main() {
-    using namespace boost;
-    using namespace boost::fusion::detail;
-
-    BOOST_TEST((and_<>::value));
-    BOOST_TEST(!(and_<false_type>::value));
-    BOOST_TEST((and_<true_type>::value));
-    BOOST_TEST(!(and_<true_type, false_type>::value));
-    BOOST_TEST((and_<true_type, true_type>::value));
-    BOOST_TEST(!(and_<true_type, true_type, false_type>::value));
-    BOOST_TEST((and_<true_type, true_type, true_type>::value));
-    BOOST_TEST((and_<true_type, mpl::true_>::value));
-
-    return boost::report_errors();
-}
-
+#ifdef BOOST_NO_CXX11_VARIADIC_TEMPLATES
+#   error "does not meet requirements"
 #endif
 
+#include <boost/fusion/support/detail/and.hpp>
+#include <boost/mpl/bool.hpp>
+#include <boost/mpl/assert.hpp>
+
+using namespace boost;
+using namespace boost::fusion::detail;
+
+BOOST_MPL_ASSERT((and_<>));
+BOOST_MPL_ASSERT_NOT((and_<false_type>));
+BOOST_MPL_ASSERT((and_<true_type>));
+BOOST_MPL_ASSERT_NOT((and_<true_type, false_type>));
+BOOST_MPL_ASSERT((and_<true_type, true_type>));
+BOOST_MPL_ASSERT_NOT((and_<true_type, true_type, false_type>));
+BOOST_MPL_ASSERT((and_<true_type, true_type, true_type>));
+BOOST_MPL_ASSERT((and_<true_type, mpl::true_>));

test/support/index_sequence.cpp

@@ -1,12 +1,14 @@
 /*=============================================================================
-    Copyright (c) 2015 Kohei Takahashi
+    Copyright (c) 2015,2018 Kohei Takahashi
 
     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/config.hpp>
 
-#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
+#ifdef BOOST_NO_CXX11_VARIADIC_TEMPLATES
+#   error "does not meet requirements"
+#endif
 
 #include <boost/fusion/support/detail/index_sequence.hpp>
 #include <boost/mpl/assert.hpp>
@@ -28,5 +30,3 @@ BOOST_MPL_ASSERT((boost::is_same<detail::make_index_sequence<15>::type, detail::
 BOOST_MPL_ASSERT((boost::is_same<detail::make_index_sequence<16>::type, detail::index_sequence<0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15> >));
 BOOST_MPL_ASSERT((boost::is_same<detail::make_index_sequence<17>::type, detail::index_sequence<0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16> >));
 
-#endif
-

test/support/is_sequence.cpp

@@ -0,0 +1,17 @@
+/*=============================================================================
+    Copyright (c) 2018 Louis Dionne
+
+    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/fusion/support/is_sequence.hpp>
+#include <boost/static_assert.hpp>
+
+
+// Make sure fusion::is_sequence and fusion::is_native_fusion_sequence can be
+// used with an incomplete type.
+struct incomplete;
+BOOST_STATIC_ASSERT(!boost::fusion::traits::is_sequence<incomplete>::value);
+BOOST_STATIC_ASSERT(!boost::fusion::traits::is_native_fusion_sequence<incomplete>::value);
+
+int main() { }

test/support/pair_conversion.cpp

@@ -0,0 +1,42 @@
+/*=============================================================================
+    Copyright (c) 2018 Kohei Takahashi
+
+    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 <utility>
+#include <boost/config.hpp>
+#include <boost/fusion/support/pair.hpp>
+
+using namespace boost::fusion;
+
+struct eat_int
+{
+    eat_int(int);
+};
+
+struct eat_pair
+{
+    template <typename K, typename V>
+    eat_pair(pair<K, V>);
+};
+
+int main()
+{
+    pair<void, int> p;
+
+    pair<void, eat_int> ci(p);
+
+#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+    pair<void, eat_int> mi(std::move(p));
+#endif
+
+    // eat_pair can't be converted from int, but can be pair.
+    // So pair(eat_pair) should be called rather than pair(pair<void, eat_pair>).
+    pair<void, eat_pair> cp(p);
+
+#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+    pair<void, eat_pair> mp(std::move(p));
+#endif
+}

test/support/pair_nest.cpp

@@ -1,5 +1,5 @@
 /*=============================================================================
-    Copyright (c) 2015 Kohei Takahashi
+    Copyright (c) 2015,2018 Kohei Takahashi
 
     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)
@@ -10,15 +10,20 @@
 using namespace boost::fusion;
 
 template <typename C>
-void copy()
+void copy(C value)
 {
-    pair<int, C> src;
+    pair<int, C> src(value);
     pair<int, C> dest = src;
     boost::ignore_unused(dest);
 }
 
 int main()
 {
-    copy<pair<void, float> >();
+    copy<pair<void, float> >(42.195f);
+    copy<pair<int, float> >(42.195f);
+
+    float f;
+    pair<void, float&> r(f);
+    copy<pair<void, float&> >(r);
 }
 

test/support/pair_trivially_copyable.cpp

@@ -0,0 +1,50 @@
+/*=============================================================================
+    Copyright (c) 2018 Kohei Takahashi
+
+    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 <type_traits>
+#include <boost/fusion/support/pair.hpp>
+#include <boost/mpl/assert.hpp>
+
+using namespace boost::fusion;
+
+struct non_trivially_copyable
+{
+    non_trivially_copyable(const non_trivially_copyable&);
+    non_trivially_copyable operator=(const non_trivially_copyable&);
+};
+
+struct pod { };
+
+BOOST_MPL_ASSERT_NOT((std::is_trivially_copyable<void>));
+BOOST_MPL_ASSERT((std::is_trivially_copyable<int>));
+BOOST_MPL_ASSERT_NOT((std::is_trivially_copyable<non_trivially_copyable>));
+BOOST_MPL_ASSERT((std::is_trivially_copyable<pod>));
+BOOST_MPL_ASSERT_NOT((std::is_trivially_copyable<int&>));
+BOOST_MPL_ASSERT((std::is_trivially_copyable<void*>));
+
+
+
+BOOST_MPL_ASSERT((std::is_trivially_copyable<pair<void, int> >));
+BOOST_MPL_ASSERT((std::is_trivially_copyable<pair<int, int> >));
+BOOST_MPL_ASSERT((std::is_trivially_copyable<pair<non_trivially_copyable, int> >));
+BOOST_MPL_ASSERT_NOT((std::is_trivially_copyable<pair<int, non_trivially_copyable> >));
+BOOST_MPL_ASSERT((std::is_trivially_copyable<pair<pod, int> >));
+BOOST_MPL_ASSERT((std::is_trivially_copyable<pair<int, pod> >));
+
+BOOST_MPL_ASSERT((std::is_trivially_copyable<pair<void, int&> >));
+BOOST_MPL_ASSERT((std::is_trivially_copyable<pair<int, int&> >));
+BOOST_MPL_ASSERT((std::is_trivially_copyable<pair<non_trivially_copyable, int&> >));
+BOOST_MPL_ASSERT((std::is_trivially_copyable<pair<int, non_trivially_copyable&> >));
+BOOST_MPL_ASSERT((std::is_trivially_copyable<pair<int, pod&> >));
+BOOST_MPL_ASSERT((std::is_trivially_copyable<pair<int, pod&> >));
+
+BOOST_MPL_ASSERT((std::is_trivially_copyable<pair<void, int*> >));
+BOOST_MPL_ASSERT((std::is_trivially_copyable<pair<int, int*> >));
+BOOST_MPL_ASSERT((std::is_trivially_copyable<pair<non_trivially_copyable, int*> >));
+BOOST_MPL_ASSERT((std::is_trivially_copyable<pair<int, non_trivially_copyable*> >));
+BOOST_MPL_ASSERT((std::is_trivially_copyable<pair<int, pod*> >));
+BOOST_MPL_ASSERT((std::is_trivially_copyable<pair<int, pod*> >));

test/support/tag_of.cpp

@@ -0,0 +1,17 @@
+/*=============================================================================
+    Copyright (c) 2018 Louis Dionne
+
+    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/fusion/support/tag_of.hpp>
+#include <boost/static_assert.hpp>
+#include <boost/type_traits/is_same.hpp>
+
+
+// Make sure tag_of can be used with an incomplete type.
+struct incomplete;
+typedef boost::fusion::traits::tag_of<incomplete>::type Tag;
+BOOST_STATIC_ASSERT((boost::is_same<Tag, boost::fusion::non_fusion_tag>::value));
+
+int main() { }