1 //////////////////////////////////////////////////////////////////////////////
2 // (C) Copyright John Maddock 2000.
3 // (C) Copyright Ion Gaztanaga 2005-2015.
4 //
5 // Distributed under the Boost Software License, Version 1.0.
6 // (See accompanying file LICENSE_1_0.txt or copy at
7 // http://www.boost.org/LICENSE_1_0.txt)
8 //
9 // See http://www.boost.org/libs/move for documentation.
10 //
11 // The alignment and Type traits implementation comes from
12 // John Maddock's TypeTraits library.
13 //
14 // Some other tricks come from Howard Hinnant's papers and StackOverflow replies
15 //////////////////////////////////////////////////////////////////////////////
16 #ifndef BOOST_MOVE_DETAIL_TYPE_TRAITS_HPP
17 #define BOOST_MOVE_DETAIL_TYPE_TRAITS_HPP
18 
19 #ifndef BOOST_CONFIG_HPP
20 #  include <boost/config.hpp>
21 #endif
22 #
23 #if defined(BOOST_HAS_PRAGMA_ONCE)
24 #  pragma once
25 #endif
26 
27 #include <boost/move/detail/config_begin.hpp>
28 #include <boost/move/detail/workaround.hpp>
29 
30 // move/detail
31 #include <boost/move/detail/meta_utils.hpp>
32 // other
33 #include <boost/assert.hpp>
34 #include <boost/static_assert.hpp>
35 // std
36 #include <cstddef>
37 
38 //Use of Boost.TypeTraits leads to long preprocessed source code due to
39 //MPL dependencies. We'll use intrinsics directly and make or own
40 //simplified version of TypeTraits.
41 //If someday Boost.TypeTraits dependencies are minimized, we should
42 //revisit this file redirecting code to Boost.TypeTraits traits.
43 
44 //These traits don't care about volatile, reference or other checks
45 //made by Boost.TypeTraits because no volatile or reference types
46 //can be hold in Boost.Containers. This helps to avoid any Boost.TypeTraits
47 //dependency.
48 
49 // Helper macros for builtin compiler support.
50 // If your compiler has builtin support for any of the following
51 // traits concepts, then redefine the appropriate macros to pick
52 // up on the compiler support:
53 //
54 // (these should largely ignore cv-qualifiers)
55 // BOOST_MOVE_IS_POD(T) should evaluate to true if T is a POD type
56 // BOOST_MOVE_HAS_TRIVIAL_CONSTRUCTOR(T) should evaluate to true if "T x;" has no effect
57 // BOOST_MOVE_HAS_TRIVIAL_COPY(T) should evaluate to true if T(t) <==> memcpy
58 // (Note: this trait does not guarantee T is copy constructible, the copy constructor could be deleted but still be trivial)
59 // BOOST_MOVE_HAS_TRIVIAL_MOVE_CONSTRUCTOR(T) should evaluate to true if T(boost::move(t)) <==> memcpy
60 // BOOST_MOVE_HAS_TRIVIAL_ASSIGN(T) should evaluate to true if t = u <==> memcpy
61 // (Note: this trait does not guarantee T is assignable , the copy assignmen could be deleted but still be trivial)
62 // BOOST_MOVE_HAS_TRIVIAL_MOVE_ASSIGN(T) should evaluate to true if t = boost::move(u) <==> memcpy
63 // BOOST_MOVE_HAS_TRIVIAL_DESTRUCTOR(T) should evaluate to true if ~T() has no effect
64 // BOOST_MOVE_HAS_NOTHROW_CONSTRUCTOR(T) should evaluate to true if "T x;" can not throw
65 // BOOST_MOVE_HAS_NOTHROW_COPY(T) should evaluate to true if T(t) can not throw
66 // BOOST_MOVE_HAS_NOTHROW_ASSIGN(T) should evaluate to true if t = u can not throw
67 // BOOST_MOVE_IS_ENUM(T) should evaluate to true it t is a union type.
68 // BOOST_MOVE_HAS_NOTHROW_MOVE_CONSTRUCT(T) should evaluate to true if T has a non-throwing move constructor.
69 // BOOST_MOVE_HAS_NOTHROW_MOVE_ASSIGN(T) should evaluate to true if T has a non-throwing move assignment operator.
70 //
71 // The following can also be defined: when detected our implementation is greatly simplified.
72 //
73 // BOOST_ALIGNMENT_OF(T) should evaluate to the alignment requirements of type T.
74 
75 #if defined(__MSL_CPP__) && (__MSL_CPP__ >= 0x8000)
76     // Metrowerks compiler is acquiring intrinsic type traits support
77     // post version 8.  We hook into the published interface to pick up
78     // user defined specializations as well as compiler intrinsics as
79     // and when they become available:
80 #   include <msl_utility>
81 #   define BOOST_MOVE_IS_UNION(T) BOOST_STD_EXTENSION_NAMESPACE::is_union<T>::value
82 #   define BOOST_MOVE_IS_POD(T) BOOST_STD_EXTENSION_NAMESPACE::is_POD<T>::value
83 #   define BOOST_MOVE_HAS_TRIVIAL_CONSTRUCTOR(T) BOOST_STD_EXTENSION_NAMESPACE::has_trivial_default_ctor<T>::value
84 #   define BOOST_MOVE_HAS_TRIVIAL_COPY(T) BOOST_STD_EXTENSION_NAMESPACE::has_trivial_copy_ctor<T>::value
85 #   define BOOST_MOVE_HAS_TRIVIAL_ASSIGN(T) BOOST_STD_EXTENSION_NAMESPACE::has_trivial_assignment<T>::value
86 #   define BOOST_MOVE_HAS_TRIVIAL_DESTRUCTOR(T) BOOST_STD_EXTENSION_NAMESPACE::has_trivial_dtor<T>::value
87 #endif
88 
89 #if (defined(BOOST_MSVC) && defined(BOOST_MSVC_FULL_VER) && (BOOST_MSVC_FULL_VER >=140050215))\
90          || (defined(BOOST_INTEL) && defined(_MSC_VER) && (_MSC_VER >= 1500))
91 #   define BOOST_MOVE_IS_UNION(T) __is_union(T)
92 #   define BOOST_MOVE_IS_POD(T)                    (__is_pod(T) && __has_trivial_constructor(T))
93 #   define BOOST_MOVE_IS_EMPTY(T)                  __is_empty(T)
94 #   define BOOST_MOVE_HAS_TRIVIAL_CONSTRUCTOR(T)   __has_trivial_constructor(T)
95 #   define BOOST_MOVE_HAS_TRIVIAL_COPY(T)          (__has_trivial_copy(T)|| ::boost::move_detail::is_pod<T>::value)
96 #   define BOOST_MOVE_HAS_TRIVIAL_ASSIGN(T)        (__has_trivial_assign(T) || ::boost::move_detail::is_pod<T>::value)
97 #   define BOOST_MOVE_HAS_TRIVIAL_DESTRUCTOR(T)    (__has_trivial_destructor(T) || ::boost::move_detail::is_pod<T>::value)
98 #   define BOOST_MOVE_HAS_NOTHROW_CONSTRUCTOR(T)   (__has_nothrow_constructor(T) || ::boost::move_detail::is_trivially_default_constructible<T>::value)
99 #   define BOOST_MOVE_HAS_NOTHROW_COPY(T)          (__has_nothrow_copy(T) || ::boost::move_detail::is_trivially_copy_constructible<T>::value)
100 #   define BOOST_MOVE_HAS_NOTHROW_ASSIGN(T)        (__has_nothrow_assign(T) || ::boost::move_detail::is_trivially_copy_assignable<T>::value)
101 
102 #   define BOOST_MOVE_IS_ENUM(T) __is_enum(T)
103 #   if defined(_MSC_VER) && (_MSC_VER >= 1700)
104 #       define BOOST_MOVE_HAS_TRIVIAL_MOVE_CONSTRUCTOR(T)   (__has_trivial_move_constructor(T) || ::boost::move_detail::is_pod<T>::value)
105 #       define BOOST_MOVE_HAS_TRIVIAL_MOVE_ASSIGN(T)        (__has_trivial_move_assign(T) || ::boost::move_detail::is_pod<T>::value)
106 #   endif
107 #  if _MSC_FULL_VER >= 180020827
108 #     define BOOST_MOVE_HAS_NOTHROW_MOVE_ASSIGN(T) (__is_nothrow_assignable(T&, T&&))
109 #     define BOOST_MOVE_HAS_NOTHROW_MOVE_CONSTRUCT(T) (__is_nothrow_constructible(T, T&&))
110 #  endif
111 #endif
112 
113 #if defined(BOOST_CLANG)
114 //    BOOST_MOVE_HAS_TRAIT
115 #   ifdef __has_extension
116 #     define BOOST_MOVE_HAS_TRAIT(T) __has_extension(T)
117 #   else
118 #     define BOOST_MOVE_HAS_TRAIT(T) 0
119 #   endif
120 
121 //    BOOST_MOVE_IS_UNION
122 #   if BOOST_MOVE_HAS_TRAIT(is_union)
123 #     define BOOST_MOVE_IS_UNION(T) __is_union(T)
124 #   endif
125 
126 //    BOOST_MOVE_IS_ENUM
127 #   if BOOST_MOVE_HAS_TRAIT(is_enum)
128 #     define BOOST_MOVE_IS_ENUM(T) __is_enum(T)
129 #   endif
130 
131 //    BOOST_MOVE_IS_POD
132 #   if (!defined(__GLIBCXX__) || (__GLIBCXX__ >= 20080306 && __GLIBCXX__ != 20080519)) && BOOST_MOVE_HAS_TRAIT(is_pod)
133 #     define BOOST_MOVE_IS_POD(T) __is_pod(T)
134 #   endif
135 
136 //    BOOST_MOVE_IS_EMPTY
137 #   if (!defined(__GLIBCXX__) || (__GLIBCXX__ >= 20080306 && __GLIBCXX__ != 20080519)) && BOOST_MOVE_HAS_TRAIT(is_empty)
138 #     define BOOST_MOVE_IS_EMPTY(T) __is_empty(T)
139 #   endif
140 
141 //    BOOST_MOVE_HAS_TRIVIAL_CONSTRUCTOR
142 #   if BOOST_MOVE_HAS_TRAIT(is_constructible) && BOOST_MOVE_HAS_TRAIT(is_trivially_constructible)
143 #     define BOOST_MOVE_HAS_TRIVIAL_CONSTRUCTOR(T) __is_trivially_constructible(T)
144 #   elif BOOST_MOVE_HAS_TRAIT(has_trivial_constructor)
145 #     define BOOST_MOVE_HAS_TRIVIAL_CONSTRUCTOR(T) __has_trivial_constructor(T)
146 #   endif
147 
148 //    BOOST_MOVE_HAS_TRIVIAL_COPY
149 #   if BOOST_MOVE_HAS_TRAIT(is_constructible) && BOOST_MOVE_HAS_TRAIT(is_trivially_constructible)
150 #     define BOOST_MOVE_HAS_TRIVIAL_COPY(T) (__is_constructible(T, const T &) && __is_trivially_constructible(T, const T &))
151 #   elif BOOST_MOVE_HAS_TRAIT(has_trivial_copy)
152 #     define BOOST_MOVE_HAS_TRIVIAL_COPY(T) __has_trivial_copy(T)
153 #   endif
154 
155 //    BOOST_MOVE_HAS_TRIVIAL_ASSIGN
156 #   if BOOST_MOVE_HAS_TRAIT(is_assignable) && BOOST_MOVE_HAS_TRAIT(is_trivially_assignable)
157 #     define BOOST_MOVE_HAS_TRIVIAL_ASSIGN(T) (__is_assignable(T, const T &) && __is_trivially_assignable(T, const T &))
158 #   elif BOOST_MOVE_HAS_TRAIT(has_trivial_copy)
159 #     define BOOST_MOVE_HAS_TRIVIAL_ASSIGN(T) __has_trivial_assign(T)
160 #   endif
161 
162 //    BOOST_MOVE_HAS_TRIVIAL_DESTRUCTOR
163 #   if BOOST_MOVE_HAS_TRAIT(is_trivially_destructible)
164 #     define BOOST_MOVE_HAS_TRIVIAL_DESTRUCTOR(T) __is_trivially_destructible(T)
165 #   elif BOOST_MOVE_HAS_TRAIT(has_trivial_destructor)
166 #     define BOOST_MOVE_HAS_TRIVIAL_DESTRUCTOR(T) __has_trivial_destructor(T)
167 #   endif
168 
169 //    BOOST_MOVE_HAS_NOTHROW_CONSTRUCTOR
170 #   if BOOST_MOVE_HAS_TRAIT(is_nothrow_constructible)
171 #     define BOOST_MOVE_HAS_NOTHROW_CONSTRUCTOR(T) __is_nothrow_constructible(T)
172 #   elif BOOST_MOVE_HAS_TRAIT(has_nothrow_constructor)
173 #     define BOOST_MOVE_HAS_NOTHROW_CONSTRUCTOR(T) __has_nothrow_constructor(T)
174 #   endif
175 
176 //    BOOST_MOVE_HAS_NOTHROW_COPY
177 #   if BOOST_MOVE_HAS_TRAIT(is_constructible) && BOOST_MOVE_HAS_TRAIT(is_nothrow_constructible)
178 #     define BOOST_MOVE_HAS_NOTHROW_COPY(T) (__is_constructible(T, const T &) && __is_nothrow_constructible(T, const T &))
179 #   elif BOOST_MOVE_HAS_TRAIT(has_nothrow_copy)
180 #     define BOOST_MOVE_HAS_NOTHROW_COPY(T) (__has_nothrow_copy(T))
181 #   endif
182 
183 //    BOOST_MOVE_HAS_NOTHROW_ASSIGN
184 #   if BOOST_MOVE_HAS_TRAIT(is_assignable) && BOOST_MOVE_HAS_TRAIT(is_nothrow_assignable)
185 #     define BOOST_MOVE_HAS_NOTHROW_ASSIGN(T) (__is_assignable(T, const T &) && __is_nothrow_assignable(T, const T &))
186 #   elif BOOST_MOVE_HAS_TRAIT(has_nothrow_assign)
187 #     define BOOST_MOVE_HAS_NOTHROW_ASSIGN(T) (__has_nothrow_assign(T))
188 #   endif
189 
190 //    BOOST_MOVE_HAS_TRIVIAL_MOVE_CONSTRUCTOR
191 #   if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) && BOOST_MOVE_HAS_TRAIT(is_constructible) && BOOST_MOVE_HAS_TRAIT(is_trivially_constructible)
192 #     define BOOST_MOVE_HAS_TRIVIAL_MOVE_CONSTRUCTOR(T) (__is_constructible(T, T&&) && __is_trivially_constructible(T, T&&))
193 #   elif BOOST_MOVE_HAS_TRAIT(has_trivial_move_constructor)
194 #     define BOOST_MOVE_HAS_TRIVIAL_MOVE_CONSTRUCTOR(T) __has_trivial_move_constructor(T)
195 #   endif
196 
197 //    BOOST_MOVE_HAS_TRIVIAL_MOVE_ASSIGN
198 #   if BOOST_MOVE_HAS_TRAIT(is_assignable) && BOOST_MOVE_HAS_TRAIT(is_trivially_assignable)
199 #     define BOOST_MOVE_HAS_TRIVIAL_MOVE_ASSIGN(T) (__is_assignable(T, T&&) && __is_trivially_assignable(T, T&&))
200 #   elif BOOST_MOVE_HAS_TRAIT(has_trivial_move_assign)
201 #     define BOOST_MOVE_HAS_TRIVIAL_MOVE_ASSIGN(T) __has_trivial_move_assign(T)
202 #   endif
203 #   define BOOST_MOVE_ALIGNMENT_OF(T) __alignof(T)
204 
205 #endif   //#if defined(BOOST_CLANG)
206 
207 #if defined(__GNUC__) && ((__GNUC__ > 4) || ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 3) && !defined(__GCCXML__))) && !defined(BOOST_CLANG)
208 
209 #ifdef BOOST_INTEL
210 #  define BOOST_MOVE_INTEL_TT_OPTS || ::boost::move_detail::is_pod<T>::value
211 #else
212 #  define BOOST_MOVE_INTEL_TT_OPTS
213 #endif
214 
215 #   define BOOST_MOVE_IS_UNION(T) __is_union(T)
216 #   define BOOST_MOVE_IS_POD(T) __is_pod(T)
217 #   define BOOST_MOVE_IS_EMPTY(T) __is_empty(T)
218 #   define BOOST_MOVE_HAS_TRIVIAL_CONSTRUCTOR(T) ((__has_trivial_constructor(T) BOOST_MOVE_INTEL_TT_OPTS))
219 
220 #   if defined(BOOST_GCC) && (BOOST_GCC > 50000)
221 #     define BOOST_MOVE_HAS_TRIVIAL_COPY(T) (__is_trivially_constructible(T, const T &))
222 #     define BOOST_MOVE_HAS_TRIVIAL_ASSIGN(T) (__is_trivially_assignable(T, const T &))
223 #   else
224 #     define BOOST_MOVE_HAS_TRIVIAL_COPY(T) ((__has_trivial_copy(T) BOOST_MOVE_INTEL_TT_OPTS))
225 #     define BOOST_MOVE_HAS_TRIVIAL_ASSIGN(T) ((__has_trivial_assign(T) BOOST_MOVE_INTEL_TT_OPTS) )
226 #   endif
227 
228 #   define BOOST_MOVE_HAS_TRIVIAL_DESTRUCTOR(T) (__has_trivial_destructor(T) BOOST_MOVE_INTEL_TT_OPTS)
229 #   define BOOST_MOVE_HAS_NOTHROW_CONSTRUCTOR(T) (__has_nothrow_constructor(T) BOOST_MOVE_INTEL_TT_OPTS)
230 #   define BOOST_MOVE_HAS_NOTHROW_COPY(T) ((__has_nothrow_copy(T) BOOST_MOVE_INTEL_TT_OPTS))
231 #   define BOOST_MOVE_HAS_NOTHROW_ASSIGN(T) ((__has_nothrow_assign(T) BOOST_MOVE_INTEL_TT_OPTS))
232 
233 #   define BOOST_MOVE_IS_ENUM(T) __is_enum(T)
234 #   if (!defined(unix) && !defined(__unix__)) || defined(__LP64__)
235       // GCC sometimes lies about alignment requirements
236       // of type double on 32-bit unix platforms, use the
237       // old implementation instead in that case:
238 #     define BOOST_MOVE_ALIGNMENT_OF(T) __alignof__(T)
239 #   endif
240 #endif
241 
242 #if defined(__ghs__) && (__GHS_VERSION_NUMBER >= 600)
243 
244 #   define BOOST_MOVE_IS_UNION(T) __is_union(T)
245 #   define BOOST_MOVE_IS_POD(T) __is_pod(T)
246 #   define BOOST_MOVE_IS_EMPTY(T) __is_empty(T)
247 #   define BOOST_MOVE_HAS_TRIVIAL_CONSTRUCTOR(T) __has_trivial_constructor(T)
248 #   define BOOST_MOVE_HAS_TRIVIAL_COPY(T) (__has_trivial_copy(T))
249 #   define BOOST_MOVE_HAS_TRIVIAL_ASSIGN(T) (__has_trivial_assign(T))
250 #   define BOOST_MOVE_HAS_TRIVIAL_DESTRUCTOR(T) __has_trivial_destructor(T)
251 #   define BOOST_MOVE_HAS_NOTHROW_CONSTRUCTOR(T) __has_nothrow_constructor(T)
252 #   define BOOST_MOVE_HAS_NOTHROW_COPY(T) (__has_nothrow_copy(T))
253 #   define BOOST_MOVE_HAS_NOTHROW_ASSIGN(T) (__has_nothrow_assign(T))
254 
255 #   define BOOST_MOVE_IS_ENUM(T) __is_enum(T)
256 #   define BOOST_MOVE_ALIGNMENT_OF(T) __alignof__(T)
257 #endif
258 
259 # if defined(BOOST_CODEGEARC)
260 #   define BOOST_MOVE_IS_UNION(T) __is_union(T)
261 #   define BOOST_MOVE_IS_POD(T) __is_pod(T)
262 #   define BOOST_MOVE_IS_EMPTY(T) __is_empty(T)
263 #   define BOOST_MOVE_HAS_TRIVIAL_CONSTRUCTOR(T) (__has_trivial_default_constructor(T))
264 #   define BOOST_MOVE_HAS_TRIVIAL_COPY(T) (__has_trivial_copy_constructor(T))
265 #   define BOOST_MOVE_HAS_TRIVIAL_ASSIGN(T) (__has_trivial_assign(T))
266 #   define BOOST_MOVE_HAS_TRIVIAL_DESTRUCTOR(T) (__has_trivial_destructor(T))
267 #   define BOOST_MOVE_HAS_NOTHROW_CONSTRUCTOR(T) (__has_nothrow_default_constructor(T))
268 #   define BOOST_MOVE_HAS_NOTHROW_COPY(T) (__has_nothrow_copy_constructor(T))
269 #   define BOOST_MOVE_HAS_NOTHROW_ASSIGN(T) (__has_nothrow_assign(T))
270 
271 #   define BOOST_MOVE_IS_ENUM(T) __is_enum(T)
272 #   define BOOST_MOVE_ALIGNMENT_OF(T) alignof(T)
273 
274 #endif
275 
276 //Fallback definitions
277 
278 #ifdef BOOST_MOVE_IS_UNION
279    #define BOOST_MOVE_IS_UNION_IMPL(T) BOOST_MOVE_IS_UNION(T)
280 #else
281    #define BOOST_MOVE_IS_UNION_IMPL(T) false
282 #endif
283 
284 #ifdef BOOST_MOVE_IS_POD
285    //in some compilers the intrinsic is limited to class types so add scalar and void
286    #define BOOST_MOVE_IS_POD_IMPL(T) (::boost::move_detail::is_scalar<T>::value ||\
287                                       ::boost::move_detail::is_void<T>::value   ||\
288                                        BOOST_MOVE_IS_POD(T))
289 #else
290    #define BOOST_MOVE_IS_POD_IMPL(T) \
291       (::boost::move_detail::is_scalar<T>::value || ::boost::move_detail::is_void<T>::value)
292 #endif
293 
294 #ifdef BOOST_MOVE_IS_EMPTY
295    #define BOOST_MOVE_IS_EMPTY_IMPL(T) BOOST_MOVE_IS_EMPTY(T)
296 #else
297    #define BOOST_MOVE_IS_EMPTY_IMPL(T)    ::boost::move_detail::is_empty_nonintrinsic<T>::value
298 #endif
299 
300 #ifdef BOOST_MOVE_HAS_TRIVIAL_COPY
301    #define BOOST_MOVE_IS_TRIVIALLY_COPY_CONSTRUCTIBLE(T)   ::boost::move_detail::is_pod<T>::value ||\
302                                                           (::boost::move_detail::is_copy_constructible<T>::value &&\
303                                                            BOOST_MOVE_HAS_TRIVIAL_COPY(T))
304 #else
305    #define BOOST_MOVE_IS_TRIVIALLY_COPY_CONSTRUCTIBLE(T)   ::boost::move_detail::is_pod<T>::value
306 #endif
307 
308 #ifdef BOOST_MOVE_HAS_TRIVIAL_CONSTRUCTOR
309    #define BOOST_MOVE_IS_TRIVIALLY_DEFAULT_CONSTRUCTIBLE(T)  BOOST_MOVE_HAS_TRIVIAL_CONSTRUCTOR(T) || ::boost::move_detail::is_pod<T>::value
310 #else
311    #define BOOST_MOVE_IS_TRIVIALLY_DEFAULT_CONSTRUCTIBLE(T)  ::boost::move_detail::is_pod<T>::value
312 #endif
313 
314 #ifdef BOOST_MOVE_HAS_TRIVIAL_MOVE_CONSTRUCTOR
315    #define BOOST_MOVE_IS_TRIVIALLY_MOVE_CONSTRUCTIBLE(T)   BOOST_MOVE_HAS_TRIVIAL_MOVE_CONSTRUCTOR(T) || ::boost::move_detail::is_pod<T>::value
316 #else
317    #define BOOST_MOVE_IS_TRIVIALLY_MOVE_CONSTRUCTIBLE(T)   ::boost::move_detail::is_pod<T>::value
318 #endif
319 
320 #ifdef BOOST_MOVE_HAS_TRIVIAL_ASSIGN
321    #define BOOST_MOVE_IS_TRIVIALLY_COPY_ASSIGNABLE(T) ::boost::move_detail::is_pod<T>::value ||\
322                                                       ( ::boost::move_detail::is_copy_assignable<T>::value &&\
323                                                          BOOST_MOVE_HAS_TRIVIAL_ASSIGN(T))
324 #else
325    #define BOOST_MOVE_IS_TRIVIALLY_COPY_ASSIGNABLE(T) ::boost::move_detail::is_pod<T>::value
326 #endif
327 
328 #ifdef BOOST_MOVE_HAS_TRIVIAL_MOVE_ASSIGN
329    #define BOOST_MOVE_IS_TRIVIALLY_MOVE_ASSIGNABLE(T)  BOOST_MOVE_HAS_TRIVIAL_MOVE_ASSIGN(T) || ::boost::move_detail::is_pod<T>::value
330 #else
331    #define BOOST_MOVE_IS_TRIVIALLY_MOVE_ASSIGNABLE(T)  ::boost::move_detail::is_pod<T>::value
332 #endif
333 
334 #ifdef BOOST_MOVE_HAS_TRIVIAL_DESTRUCTOR
335    #define BOOST_MOVE_IS_TRIVIALLY_DESTRUCTIBLE(T)   BOOST_MOVE_HAS_TRIVIAL_DESTRUCTOR(T) || ::boost::move_detail::is_pod<T>::value
336 #else
337    #define BOOST_MOVE_IS_TRIVIALLY_DESTRUCTIBLE(T)   ::boost::move_detail::is_pod<T>::value
338 #endif
339 
340 #ifdef BOOST_MOVE_HAS_NOTHROW_CONSTRUCTOR
341    #define BOOST_MOVE_IS_NOTHROW_DEFAULT_CONSTRUCTIBLE(T)  BOOST_MOVE_HAS_NOTHROW_CONSTRUCTOR(T) || ::boost::move_detail::is_pod<T>::value
342 #else
343    #define BOOST_MOVE_IS_NOTHROW_DEFAULT_CONSTRUCTIBLE(T)  ::boost::move_detail::is_pod<T>::value
344 #endif
345 
346 #ifdef BOOST_MOVE_HAS_NOTHROW_COPY
347    #define BOOST_MOVE_IS_NOTHROW_COPY_CONSTRUCTIBLE(T)   BOOST_MOVE_HAS_NOTHROW_COPY(T) || ::boost::move_detail::is_pod<T>::value
348 #else
349    #define BOOST_MOVE_IS_NOTHROW_COPY_CONSTRUCTIBLE(T)   BOOST_MOVE_IS_TRIVIALLY_COPY_ASSIGNABLE(T)
350 #endif
351 
352 #ifdef BOOST_MOVE_HAS_NOTHROW_ASSIGN
353    #define BOOST_MOVE_IS_NOTHROW_COPY_ASSIGNABLE(T) BOOST_MOVE_HAS_NOTHROW_ASSIGN(T) || ::boost::move_detail::is_pod<T>::value
354 #else
355    #define BOOST_MOVE_IS_NOTHROW_COPY_ASSIGNABLE(T) BOOST_MOVE_IS_TRIVIALLY_COPY_ASSIGNABLE(T)
356 #endif
357 
358 #ifdef BOOST_MOVE_HAS_NOTHROW_MOVE_CONSTRUCT
359    #define BOOST_MOVE_IS_NOTHROW_MOVE_CONSTRUCTIBLE(T)   BOOST_MOVE_HAS_NOTHROW_MOVE_CONSTRUCT(T) || ::boost::move_detail::is_pod<T>::value
360 #else
361    #define BOOST_MOVE_IS_NOTHROW_MOVE_CONSTRUCTIBLE(T)   BOOST_MOVE_IS_TRIVIALLY_MOVE_ASSIGNABLE(T)
362 #endif
363 
364 #ifdef BOOST_MOVE_HAS_NOTHROW_MOVE_ASSIGN
365    #define BOOST_MOVE_IS_NOTHROW_MOVE_ASSIGNABLE(T) BOOST_MOVE_HAS_NOTHROW_MOVE_ASSIGN(T) || ::boost::move_detail::is_pod<T>::value
366 #else
367    #define BOOST_MOVE_IS_NOTHROW_MOVE_ASSIGNABLE(T) BOOST_MOVE_IS_TRIVIALLY_MOVE_ASSIGNABLE(T)
368 #endif
369 
370 #ifdef BOOST_MOVE_IS_ENUM
371    #define BOOST_MOVE_IS_ENUM_IMPL(T)   BOOST_MOVE_IS_ENUM(T)
372 #else
373    #define BOOST_MOVE_IS_ENUM_IMPL(T)   ::boost::move_detail::is_enum_nonintrinsic<T>::value
374 #endif
375 
376 namespace boost {
377 namespace move_detail {
378 
379 //////////////////////////
380 //    is_reference
381 //////////////////////////
382 template<class T>
383 struct is_reference
384 {  static const bool value = false; };
385 
386 template<class T>
387 struct is_reference<T&>
388 {  static const bool value = true; };
389 
390 #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
391 template<class T>
392 struct is_reference<T&&>
393 {  static const bool value = true; };
394 #endif
395 
396 //////////////////////////
397 //    is_pointer
398 //////////////////////////
399 template<class T>
400 struct is_pointer
401 {  static const bool value = false; };
402 
403 template<class T>
404 struct is_pointer<T*>
405 {  static const bool value = true; };
406 
407 //////////////////////////
408 //       is_const
409 //////////////////////////
410 template<class T>
411 struct is_const
412 {  static const bool value = false; };
413 
414 template<class T>
415 struct is_const<const T>
416 {  static const bool value = true; };
417 
418 //////////////////////////
419 //       unvoid_ref
420 //////////////////////////
421 template <typename T> struct unvoid_ref : add_lvalue_reference<T>{};
422 template <> struct unvoid_ref<void>                { typedef unvoid_ref & type; };
423 template <> struct unvoid_ref<const void>          { typedef unvoid_ref & type; };
424 template <> struct unvoid_ref<volatile void>       { typedef unvoid_ref & type; };
425 template <> struct unvoid_ref<const volatile void> { typedef unvoid_ref & type; };
426 
427 template <typename T>
428 struct add_reference : add_lvalue_reference<T>
429 {};
430 
431 //////////////////////////
432 //    add_const_reference
433 //////////////////////////
434 template <class T>
435 struct add_const_reference
436 {  typedef const T &type;   };
437 
438 template <class T>
439 struct add_const_reference<T&>
440 {  typedef T& type;   };
441 
442 //////////////////////////
443 //    add_const_if_c
444 //////////////////////////
445 template<class T, bool Add>
446 struct add_const_if_c
447    : if_c<Add, typename add_const<T>::type, T>
448 {};
449 
450 //////////////////////////
451 //    remove_const
452 //////////////////////////
453 template<class T>
454 struct remove_const
455 {  typedef T type;   };
456 
457 template<class T>
458 struct remove_const< const T>
459 {  typedef T type;   };
460 
461 //////////////////////////
462 //    remove_cv
463 //////////////////////////
464 template<typename T> struct remove_cv                    {  typedef T type;   };
465 template<typename T> struct remove_cv<const T>           {  typedef T type;   };
466 template<typename T> struct remove_cv<const volatile T>  {  typedef T type;   };
467 template<typename T> struct remove_cv<volatile T>        {  typedef T type;   };
468 
469 //////////////////////////
470 //    remove_cvref
471 //////////////////////////
472 template<class T>
473 struct remove_cvref
474    : remove_cv<typename remove_reference<T>::type>
475 {
476 };
477 
478 //////////////////////////
479 //    make_unsigned
480 //////////////////////////
481 template <class T>
482 struct make_unsigned_impl                                         {  typedef T type;   };
483 template <> struct make_unsigned_impl<signed char>                {  typedef unsigned char  type; };
484 template <> struct make_unsigned_impl<signed short>               {  typedef unsigned short type; };
485 template <> struct make_unsigned_impl<signed int>                 {  typedef unsigned int   type; };
486 template <> struct make_unsigned_impl<signed long>                {  typedef unsigned long  type; };
487 #ifdef BOOST_HAS_LONG_LONG
488 template <> struct make_unsigned_impl< ::boost::long_long_type >  {  typedef ::boost::ulong_long_type type; };
489 #endif
490 
491 template <class T>
492 struct make_unsigned
493    : make_unsigned_impl<typename remove_cv<T>::type>
494 {};
495 
496 //////////////////////////
497 //    is_floating_point
498 //////////////////////////
499 template<class T> struct is_floating_point_cv               {  static const bool value = false; };
500 template<>        struct is_floating_point_cv<float>        {  static const bool value = true; };
501 template<>        struct is_floating_point_cv<double>       {  static const bool value = true; };
502 template<>        struct is_floating_point_cv<long double>  {  static const bool value = true; };
503 
504 template<class T>
505 struct is_floating_point
506    : is_floating_point_cv<typename remove_cv<T>::type>
507 {};
508 
509 //////////////////////////
510 //    is_integral
511 //////////////////////////
512 template<class T> struct is_integral_cv                    {  static const bool value = false; };
513 template<> struct is_integral_cv<                     bool>{  static const bool value = true; };
514 template<> struct is_integral_cv<                     char>{  static const bool value = true; };
515 template<> struct is_integral_cv<            unsigned char>{  static const bool value = true; };
516 template<> struct is_integral_cv<              signed char>{  static const bool value = true; };
517 #ifndef BOOST_NO_CXX11_CHAR16_T
518 template<> struct is_integral_cv<                 char16_t>{  static const bool value = true; };
519 #endif
520 #ifndef BOOST_NO_CXX11_CHAR32_T
521 template<> struct is_integral_cv<                 char32_t>{  static const bool value = true; };
522 #endif
523 #ifndef BOOST_NO_INTRINSIC_WCHAR_T
524 template<> struct is_integral_cv<                  wchar_t>{  static const bool value = true; };
525 #endif
526 template<> struct is_integral_cv<                    short>{  static const bool value = true; };
527 template<> struct is_integral_cv<           unsigned short>{  static const bool value = true; };
528 template<> struct is_integral_cv<                      int>{  static const bool value = true; };
529 template<> struct is_integral_cv<             unsigned int>{  static const bool value = true; };
530 template<> struct is_integral_cv<                     long>{  static const bool value = true; };
531 template<> struct is_integral_cv<            unsigned long>{  static const bool value = true; };
532 #ifdef BOOST_HAS_LONG_LONG
533 template<> struct is_integral_cv< ::boost:: long_long_type>{  static const bool value = true; };
534 template<> struct is_integral_cv< ::boost::ulong_long_type>{  static const bool value = true; };
535 #endif
536 
537 template<class T>
538 struct is_integral
539    : public is_integral_cv<typename remove_cv<T>::type>
540 {};
541 
542 //////////////////////////////////////
543 //          remove_all_extents
544 //////////////////////////////////////
545 template <class T>
546 struct remove_all_extents
547 {  typedef T type;};
548 
549 template <class T>
550 struct remove_all_extents<T[]>
551 {  typedef typename remove_all_extents<T>::type type; };
552 
553 template <class T, std::size_t N>
554 struct remove_all_extents<T[N]>
555 {  typedef typename remove_all_extents<T>::type type;};
556 
557 //////////////////////////
558 //    is_scalar
559 //////////////////////////
560 template<class T>
561 struct is_scalar
562 {  static const bool value = is_integral<T>::value || is_floating_point<T>::value; };
563 
564 //////////////////////////
565 //       is_void
566 //////////////////////////
567 template<class T>
568 struct is_void_cv
569 {  static const bool value = false; };
570 
571 template<>
572 struct is_void_cv<void>
573 {  static const bool value = true; };
574 
575 template<class T>
576 struct is_void
577    : is_void_cv<typename remove_cv<T>::type>
578 {};
579 
580 //////////////////////////////////////
581 //          is_array
582 //////////////////////////////////////
583 template<class T>
584 struct is_array
585 {  static const bool value = false; };
586 
587 template<class T>
588 struct is_array<T[]>
589 {  static const bool value = true;  };
590 
591 template<class T, std::size_t N>
592 struct is_array<T[N]>
593 {  static const bool value = true;  };
594 
595 //////////////////////////////////////
596 //           is_member_pointer
597 //////////////////////////////////////
598 template <class T>         struct is_member_pointer_cv         {  static const bool value = false; };
599 template <class T, class U>struct is_member_pointer_cv<T U::*> {  static const bool value = true; };
600 
601 template <class T>
602 struct is_member_pointer
603     : is_member_pointer_cv<typename remove_cv<T>::type>
604 {};
605 
606 //////////////////////////////////////
607 //          is_nullptr_t
608 //////////////////////////////////////
609 template <class T>
610 struct is_nullptr_t_cv
611 {  static const bool value = false; };
612 
613 #if !defined(BOOST_NO_CXX11_NULLPTR)
614 template <>
615 struct is_nullptr_t_cv
616    #if !defined(BOOST_NO_CXX11_DECLTYPE)
617    <decltype(nullptr)>
618    #else
619    <std::nullptr_t>
620    #endif
621 {  static const bool value = true; };
622 #endif
623 
624 template <class T>
625 struct is_nullptr_t
626    : is_nullptr_t_cv<typename remove_cv<T>::type>
627 {};
628 
629 //////////////////////////////////////
630 //          is_function
631 //////////////////////////////////////
632 //Inspired by libc++, thanks to Howard Hinnant
633 //For a function to pointer an lvalue of function type T can be implicitly converted to a prvalue
634 //pointer to that function. This does not apply to non-static member functions because lvalues
635 //that refer to non-static member functions do not exist.
636 template <class T>
637 struct is_reference_convertible_to_pointer
638 {
639    struct twochar { char dummy[2]; };
640    template <class U> static char    test(U*);
641    template <class U> static twochar test(...);
642    static T& source();
643    static const bool value = sizeof(char) == sizeof(test<T>(source()));
644 };
645 //Filter out:
646 // - class types that might have implicit conversions
647 // - void (to avoid forming a reference to void later)
648 // - references (e.g.: filtering reference to functions)
649 // - nullptr_t (convertible to pointer)
650 template < class T
651          , bool Filter = is_class_or_union<T>::value  ||
652                          is_void<T>::value            ||
653                          is_reference<T>::value       ||
654                          is_nullptr_t<T>::value       >
655 struct is_function_impl
656 {  static const bool value = is_reference_convertible_to_pointer<T>::value; };
657 
658 template <class T>
659 struct is_function_impl<T, true>
660 {  static const bool value = false; };
661 
662 template <class T>
663 struct is_function
664    : is_function_impl<T>
665 {};
666 
667 //////////////////////////////////////
668 //       is_union
669 //////////////////////////////////////
670 template<class T>
671 struct is_union_noextents_cv
672 {  static const bool value = BOOST_MOVE_IS_UNION_IMPL(T); };
673 
674 template<class T>
675 struct is_union
676    : is_union_noextents_cv<typename remove_cv<typename remove_all_extents<T>::type>::type>
677 {};
678 
679 //////////////////////////////////////
680 //             is_class
681 //////////////////////////////////////
682 template <class T>
683 struct is_class
684 {
685    static const bool value = is_class_or_union<T>::value && ! is_union<T>::value;
686 };
687 
688 
689 //////////////////////////////////////
690 //             is_arithmetic
691 //////////////////////////////////////
692 template <class T>
693 struct is_arithmetic
694 {
695    static const bool value = is_floating_point<T>::value ||
696                              is_integral<T>::value;
697 };
698 
699 //////////////////////////////////////
700 //    is_member_function_pointer
701 //////////////////////////////////////
702 template <class T>
703 struct is_member_function_pointer_cv
704 {
705    static const bool value = false;
706 };
707 
708 template <class T, class C>
709 struct is_member_function_pointer_cv<T C::*>
710    : is_function<T>
711 {};
712 
713 template <class T>
714 struct is_member_function_pointer
715     : is_member_function_pointer_cv<typename remove_cv<T>::type>
716 {};
717 
718 //////////////////////////////////////
719 //             is_enum
720 //////////////////////////////////////
721 #if !defined(BOOST_MOVE_IS_ENUM)
722 //Based on (http://howardhinnant.github.io/TypeHiearchy.pdf)
723 template <class T>
724 struct is_enum_nonintrinsic
725 {
726    static const bool value =  !is_arithmetic<T>::value     &&
727                               !is_reference<T>::value      &&
728                               !is_class_or_union<T>::value &&
729                               !is_array<T>::value          &&
730                               !is_void<T>::value           &&
731                               !is_nullptr_t<T>::value      &&
732                               !is_member_pointer<T>::value &&
733                               !is_pointer<T>::value        &&
734                               !is_function<T>::value;
735 };
736 #endif
737 
738 template <class T>
739 struct is_enum
740 {  static const bool value = BOOST_MOVE_IS_ENUM_IMPL(T);  };
741 
742 //////////////////////////////////////
743 //       is_pod
744 //////////////////////////////////////
745 template<class T>
746 struct is_pod_noextents_cv  //for non-c++11 compilers, a safe fallback
747 {  static const bool value = BOOST_MOVE_IS_POD_IMPL(T); };
748 
749 template<class T>
750 struct is_pod
751    : is_pod_noextents_cv<typename remove_cv<typename remove_all_extents<T>::type>::type>
752 {};
753 
754 //////////////////////////////////////
755 //             is_empty
756 //////////////////////////////////////
757 #if !defined(BOOST_MOVE_IS_EMPTY)
758 
759 template <typename T>
760 struct empty_helper_t1 : public T
761 {
762    empty_helper_t1();  // hh compiler bug workaround
763    int i[256];
764    private:
765 
766    empty_helper_t1(const empty_helper_t1&);
767    empty_helper_t1& operator=(const empty_helper_t1&);
768 };
769 
770 struct empty_helper_t2 { int i[256]; };
771 
772 template <typename T, bool IsClass = is_class<T>::value >
773 struct is_empty_nonintrinsic
774 {
775    static const bool value = false;
776 };
777 
778 template <typename T>
779 struct is_empty_nonintrinsic<T, true>
780 {
781    static const bool value = sizeof(empty_helper_t1<T>) == sizeof(empty_helper_t2);
782 };
783 #endif
784 
785 template <class T>
786 struct is_empty
787 {  static const bool value = BOOST_MOVE_IS_EMPTY_IMPL(T);  };
788 
789 
790 template<class T>
791 struct has_boost_move_no_copy_constructor_or_assign_type
792 {
793    template <class U>
794    static yes_type test(typename U::boost_move_no_copy_constructor_or_assign*);
795 
796    template <class U>
797    static no_type test(...);
798 
799    static const bool value = sizeof(test<T>(0)) == sizeof(yes_type);
800 };
801 
802 //////////////////////////////////////
803 //       is_copy_constructible
804 //////////////////////////////////////
805 #if !defined(BOOST_NO_CXX11_DELETED_FUNCTIONS) && !defined(BOOST_NO_CXX11_DECLTYPE) \
806    && !defined(BOOST_INTEL_CXX_VERSION) && \
807       !(defined(BOOST_MSVC) && _MSC_VER == 1800)
808 #define BOOST_MOVE_TT_CXX11_IS_COPY_CONSTRUCTIBLE
809 #endif
810 
811 template<class T>
812 struct is_copy_constructible
813 {
814    // Intel compiler has problems with SFINAE for copy constructors and deleted functions:
815    //
816    // error: function *function_name* cannot be referenced -- it is a deleted function
817    // static yes_type test(U&, decltype(U(boost::declval<U&>()))* = 0);
818    //                                                        ^
819    // MSVC 12.0 (Visual 2013) has problems when the copy constructor has been deleted. See:
820    // https://connect.microsoft.com/VisualStudio/feedback/details/800328/std-is-copy-constructible-is-broken
821    #if defined(BOOST_MOVE_TT_CXX11_IS_COPY_CONSTRUCTIBLE)
822       template<class U> static typename add_reference<U>::type source();
823       static no_type test(...);
824       #ifdef BOOST_NO_CXX11_DECLTYPE
825          template <class U>
826          static yes_type test(U&, bool_<sizeof(U(source<U>()))>* = 0);
827       #else
828          template <class U>
829          static yes_type test(U&, decltype(U(source<U>()))* = 0);
830       #endif
831       static const bool value = sizeof(test(source<T>())) == sizeof(yes_type);
832    #else
833    static const bool value = !has_boost_move_no_copy_constructor_or_assign_type<T>::value;
834    #endif
835 };
836 
837 
838 //////////////////////////////////////
839 //       is_copy_assignable
840 //////////////////////////////////////
841 #if !defined(BOOST_NO_CXX11_DELETED_FUNCTIONS) && !defined(BOOST_NO_CXX11_DECLTYPE) \
842    && !defined(BOOST_INTEL_CXX_VERSION) && \
843       !(defined(BOOST_MSVC) && _MSC_VER == 1800)
844 #define BOOST_MOVE_TT_CXX11_IS_COPY_ASSIGNABLE
845 #endif
846 
847 template <class T>
848 struct is_copy_assignable
849 {
850 // Intel compiler has problems with SFINAE for copy constructors and deleted functions:
851 //
852 // error: function *function_name* cannot be referenced -- it is a deleted function
853 // static boost::type_traits::yes_type test(T1&, decltype(T1(boost::declval<T1&>()))* = 0);
854 //                                                        ^
855 //
856 // MSVC 12.0 (Visual 2013) has problems when the copy constructor has been deleted. See:
857 // https://connect.microsoft.com/VisualStudio/feedback/details/800328/std-is-copy-constructible-is-broken
858 #if defined(BOOST_MOVE_TT_CXX11_IS_COPY_ASSIGNABLE)
859    typedef char yes_type;
860    struct no_type { char dummy[2]; };
861 
862    template <class U>   static typename add_reference<U>::type source();
863    template <class U>   static decltype(source<U&>() = source<const U&>(), yes_type() ) test(int);
864    template <class>     static no_type test(...);
865 
866    static const bool value = sizeof(test<T>(0)) == sizeof(yes_type);
867 #else
868    static const bool value = !has_boost_move_no_copy_constructor_or_assign_type<T>::value;
869 #endif
870 };
871 
872 //////////////////////////////////////
873 //       is_trivially_destructible
874 //////////////////////////////////////
875 template<class T>
876 struct is_trivially_destructible
877 {  static const bool value = BOOST_MOVE_IS_TRIVIALLY_DESTRUCTIBLE(T); };
878 
879 //////////////////////////////////////
880 //       is_trivially_default_constructible
881 //////////////////////////////////////
882 template<class T>
883 struct is_trivially_default_constructible
884 {  static const bool value = BOOST_MOVE_IS_TRIVIALLY_DEFAULT_CONSTRUCTIBLE(T); };
885 
886 //////////////////////////////////////
887 //       is_trivially_copy_constructible
888 //////////////////////////////////////
889 template<class T>
890 struct is_trivially_copy_constructible
891 {
892    static const bool value = BOOST_MOVE_IS_TRIVIALLY_COPY_CONSTRUCTIBLE(T);
893 };
894 
895 //////////////////////////////////////
896 //       is_trivially_move_constructible
897 //////////////////////////////////////
898 template<class T>
899 struct is_trivially_move_constructible
900 { static const bool value = BOOST_MOVE_IS_TRIVIALLY_MOVE_CONSTRUCTIBLE(T); };
901 
902 //////////////////////////////////////
903 //       is_trivially_copy_assignable
904 //////////////////////////////////////
905 template<class T>
906 struct is_trivially_copy_assignable
907 {
908    static const bool value = BOOST_MOVE_IS_TRIVIALLY_COPY_ASSIGNABLE(T);
909 };
910 
911 //////////////////////////////////////
912 //       is_trivially_move_assignable
913 //////////////////////////////////////
914 template<class T>
915 struct is_trivially_move_assignable
916 {  static const bool value = BOOST_MOVE_IS_TRIVIALLY_MOVE_ASSIGNABLE(T);  };
917 
918 //////////////////////////////////////
919 //       is_nothrow_default_constructible
920 //////////////////////////////////////
921 template<class T>
922 struct is_nothrow_default_constructible
923 {  static const bool value = BOOST_MOVE_IS_NOTHROW_DEFAULT_CONSTRUCTIBLE(T);  };
924 
925 //////////////////////////////////////
926 //    is_nothrow_copy_constructible
927 //////////////////////////////////////
928 template<class T>
929 struct is_nothrow_copy_constructible
930 {  static const bool value = BOOST_MOVE_IS_NOTHROW_COPY_CONSTRUCTIBLE(T);  };
931 
932 //////////////////////////////////////
933 //    is_nothrow_move_constructible
934 //////////////////////////////////////
935 template<class T>
936 struct is_nothrow_move_constructible
937 {  static const bool value = BOOST_MOVE_IS_NOTHROW_MOVE_CONSTRUCTIBLE(T);  };
938 
939 //////////////////////////////////////
940 //       is_nothrow_copy_assignable
941 //////////////////////////////////////
942 template<class T>
943 struct is_nothrow_copy_assignable
944 {  static const bool value = BOOST_MOVE_IS_NOTHROW_COPY_ASSIGNABLE(T);  };
945 
946 //////////////////////////////////////
947 //    is_nothrow_move_assignable
948 //////////////////////////////////////
949 template<class T>
950 struct is_nothrow_move_assignable
951 {  static const bool value = BOOST_MOVE_IS_NOTHROW_MOVE_ASSIGNABLE(T);  };
952 
953 //////////////////////////////////////
954 //    is_nothrow_swappable
955 //////////////////////////////////////
956 template<class T>
957 struct is_nothrow_swappable
958 {
959    static const bool value = is_empty<T>::value || is_pod<T>::value;
960 };
961 
962 //////////////////////////////////////
963 //       alignment_of
964 //////////////////////////////////////
965 template <typename T>
966 struct alignment_of_hack
967 {
968    T t1;
969    char c;
970    T t2;
971    alignment_of_hack();
972    ~alignment_of_hack();
973 };
974 
975 template <unsigned A, unsigned S>
976 struct alignment_logic
977 {  static const std::size_t value = A < S ? A : S; };
978 
979 template< typename T >
980 struct alignment_of_impl
981 #if defined(BOOST_MSVC) && (BOOST_MSVC >= 1400)
982     // With MSVC both the native __alignof operator
983     // and our own logic gets things wrong from time to time :-(
984     // Using a combination of the two seems to make the most of a bad job:
985    : alignment_logic< sizeof(alignment_of_hack<T>) - 2*sizeof(T), __alignof(T)>
986 {};
987 #elif !defined(BOOST_MOVE_ALIGNMENT_OF)
988    : alignment_logic< sizeof(alignment_of_hack<T>) - 2*sizeof(T), sizeof(T)>
989 {};
990 #else
991 {  static const std::size_t value = BOOST_MOVE_ALIGNMENT_OF(T);  };
992 #endif
993 
994 template< typename T >
995 struct alignment_of
996    : alignment_of_impl<T>
997 {};
998 
999 class alignment_dummy;
1000 typedef void (*function_ptr)();
1001 typedef int (alignment_dummy::*member_ptr);
1002 typedef int (alignment_dummy::*member_function_ptr)();
1003 struct alignment_struct
1004 {  long double dummy[4];  };
1005 
1006 /////////////////////////////
1007 //    max_align_t
1008 /////////////////////////////
1009 //This is not standard, but should work with all compilers
1010 union max_align
1011 {
1012    char        char_;
1013    short       short_;
1014    int         int_;
1015    long        long_;
1016    #ifdef BOOST_HAS_LONG_LONG
1017    ::boost::long_long_type   long_long_;
1018    #endif
1019    float       float_;
1020    double      double_;
1021    void *      void_ptr_;
1022    long double long_double_[4];
1023    alignment_dummy *unknown_class_ptr_;
1024    function_ptr function_ptr_;
1025    member_function_ptr member_function_ptr_;
1026    alignment_struct alignment_struct_;
1027 };
1028 
1029 typedef union max_align max_align_t;
1030 
1031 /////////////////////////////
1032 //    aligned_storage
1033 /////////////////////////////
1034 
1035 #if defined(_MSC_VER) && defined(_M_IX86)
1036 
1037 // Special version for usual alignments on x86 MSVC because it might crash
1038 // when passsing aligned types by value even for 8 byte alignment.
1039 template<std::size_t Align>
1040 struct aligned_struct;
1041 
1042 template <> struct aligned_struct<1> { char data; };
1043 template <> struct aligned_struct<2> { short data; };
1044 template <> struct aligned_struct<4> { int data; };
1045 template <> struct aligned_struct<8> { double data; };
1046 
1047 #define BOOST_MOVE_ALIGNED_STRUCT(x) \
1048   template <> struct aligned_struct<x> { \
1049     __declspec(align(x)) char data; \
1050   }
1051 BOOST_MOVE_ALIGNED_STRUCT(16);
1052 BOOST_MOVE_ALIGNED_STRUCT(32);
1053 BOOST_MOVE_ALIGNED_STRUCT(64);
1054 BOOST_MOVE_ALIGNED_STRUCT(128);
1055 BOOST_MOVE_ALIGNED_STRUCT(512);
1056 BOOST_MOVE_ALIGNED_STRUCT(1024);
1057 BOOST_MOVE_ALIGNED_STRUCT(2048);
1058 BOOST_MOVE_ALIGNED_STRUCT(4096);
1059 
1060 template<std::size_t Len, std::size_t Align>
1061 union aligned_union
1062 {
1063    typedef aligned_struct<Align> aligner_t;
1064    aligner_t aligner;
1065    unsigned char data[Len > sizeof(aligner_t) ? Len : sizeof(aligner_t)];
1066 };
1067 
1068 template<std::size_t Len, std::size_t Align>
1069 struct aligned_storage_impl
1070 {
1071    typedef aligned_union<Len, Align> type;
1072 };
1073 
1074 #elif !defined(BOOST_NO_ALIGNMENT)
1075 
1076 template<std::size_t Len, std::size_t Align>
1077 struct aligned_struct;
1078 
1079 #define BOOST_MOVE_ALIGNED_STORAGE_WITH_BOOST_ALIGNMENT(A)\
1080 template<std::size_t Len>\
1081 struct BOOST_ALIGNMENT(A) aligned_struct<Len, A>\
1082 {\
1083    unsigned char data[Len];\
1084 };\
1085 //
1086 
1087 //Up to 4K alignment (typical page size)
1088 BOOST_MOVE_ALIGNED_STORAGE_WITH_BOOST_ALIGNMENT(0x1)
1089 BOOST_MOVE_ALIGNED_STORAGE_WITH_BOOST_ALIGNMENT(0x2)
1090 BOOST_MOVE_ALIGNED_STORAGE_WITH_BOOST_ALIGNMENT(0x4)
1091 BOOST_MOVE_ALIGNED_STORAGE_WITH_BOOST_ALIGNMENT(0x8)
1092 BOOST_MOVE_ALIGNED_STORAGE_WITH_BOOST_ALIGNMENT(0x10)
1093 BOOST_MOVE_ALIGNED_STORAGE_WITH_BOOST_ALIGNMENT(0x20)
1094 BOOST_MOVE_ALIGNED_STORAGE_WITH_BOOST_ALIGNMENT(0x40)
1095 BOOST_MOVE_ALIGNED_STORAGE_WITH_BOOST_ALIGNMENT(0x80)
1096 BOOST_MOVE_ALIGNED_STORAGE_WITH_BOOST_ALIGNMENT(0x100)
1097 BOOST_MOVE_ALIGNED_STORAGE_WITH_BOOST_ALIGNMENT(0x200)
1098 BOOST_MOVE_ALIGNED_STORAGE_WITH_BOOST_ALIGNMENT(0x400)
1099 BOOST_MOVE_ALIGNED_STORAGE_WITH_BOOST_ALIGNMENT(0x800)
1100 BOOST_MOVE_ALIGNED_STORAGE_WITH_BOOST_ALIGNMENT(0x1000)
1101 
1102 #undef BOOST_MOVE_ALIGNED_STORAGE_WITH_BOOST_ALIGNMENT
1103 
1104 // Workaround for bogus [-Wignored-attributes] warning on GCC 6.x/7.x: don't use a type that "directly" carries the alignment attribute.
1105 // See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82270
1106 template<std::size_t Len, std::size_t Align>
1107 union aligned_struct_wrapper
1108 {
1109    typedef aligned_struct<Len, Align> aligner_t;
1110    aligned_struct<Len, Align> aligner;
1111    unsigned char data[Len > sizeof(aligner_t) ? Len : sizeof(aligner_t)];
1112 };
1113 
1114 template<std::size_t Len, std::size_t Align>
1115 struct aligned_storage_impl
1116 {
1117    typedef aligned_struct_wrapper<Len, Align> type;
1118 };
1119 
1120 #else //BOOST_NO_ALIGNMENT
1121 
1122 template<class T, std::size_t Len>
1123 union aligned_union
1124 {
1125    T aligner;
1126    unsigned char data[Len > sizeof(T) ? Len : sizeof(T)];
1127 };
1128 
1129 template<std::size_t Len, std::size_t Align, class T, bool Ok>
1130 struct aligned_next;
1131 
1132 template<std::size_t Len, std::size_t Align, class T>
1133 struct aligned_next<Len, Align, T, true>
1134 {
1135    BOOST_STATIC_ASSERT((alignment_of<T>::value == Align));
1136    typedef aligned_union<T, Len> type;
1137 };
1138 
1139 //End of search defaults to max_align_t
1140 template<std::size_t Len, std::size_t Align>
1141 struct aligned_next<Len, Align, max_align_t, false>
1142 {   typedef aligned_union<max_align_t, Len> type;   };
1143 
1144 //Now define a search list through types
1145 #define BOOST_MOVE_ALIGNED_NEXT_STEP(TYPE, NEXT_TYPE)\
1146    template<std::size_t Len, std::size_t Align>\
1147    struct aligned_next<Len, Align, TYPE, false>\
1148       : aligned_next<Len, Align, NEXT_TYPE, Align == alignment_of<NEXT_TYPE>::value>\
1149    {};\
1150    //
1151    BOOST_MOVE_ALIGNED_NEXT_STEP(long double, max_align_t)
1152    BOOST_MOVE_ALIGNED_NEXT_STEP(double, long double)
1153    #ifdef BOOST_HAS_LONG_LONG
1154       BOOST_MOVE_ALIGNED_NEXT_STEP(::boost::long_long_type, double)
1155       BOOST_MOVE_ALIGNED_NEXT_STEP(long, ::boost::long_long_type)
1156    #else
1157       BOOST_MOVE_ALIGNED_NEXT_STEP(long, double)
1158    #endif
1159    BOOST_MOVE_ALIGNED_NEXT_STEP(int, long)
1160    BOOST_MOVE_ALIGNED_NEXT_STEP(short, int)
1161    BOOST_MOVE_ALIGNED_NEXT_STEP(char, short)
1162 #undef BOOST_MOVE_ALIGNED_NEXT_STEP
1163 
1164 template<std::size_t Len, std::size_t Align>
1165 struct aligned_storage_impl
1166    : aligned_next<Len, Align, char, Align == alignment_of<char>::value>
1167 {};
1168 
1169 #endif
1170 
1171 template<std::size_t Len, std::size_t Align = alignment_of<max_align_t>::value>
1172 struct aligned_storage
1173 {
1174    //Sanity checks for input parameters
1175    BOOST_STATIC_ASSERT(Align > 0);
1176 
1177    //Sanity checks for output type
1178    typedef typename aligned_storage_impl<Len ? Len : 1, Align>::type type;
1179    static const std::size_t value = alignment_of<type>::value;
1180    BOOST_STATIC_ASSERT(value >= Align);
1181    BOOST_STATIC_ASSERT((value % Align) == 0);
1182 
1183    //Just in case someone instantiates aligned_storage
1184    //instead of aligned_storage::type (typical error).
1185    private:
1186    aligned_storage();
1187 };
1188 
1189 }  //namespace move_detail {
1190 }  //namespace boost {
1191 
1192 #include <boost/move/detail/config_end.hpp>
1193 
1194 #endif   //#ifndef BOOST_MOVE_DETAIL_TYPE_TRAITS_HPP
1195