1 //
2 // detail/config.hpp
3 // ~~~~~~~~~~~~~~~~~
4 //
5 // Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
6 //
7 // Distributed under the Boost Software License, Version 1.0. (See accompanying
8 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
9 //
10 
11 #ifndef BOOST_ASIO_DETAIL_CONFIG_HPP
12 #define BOOST_ASIO_DETAIL_CONFIG_HPP
13 
14 #if defined(BOOST_ASIO_STANDALONE)
15 # define BOOST_ASIO_DISABLE_BOOST_ARRAY 1
16 # define BOOST_ASIO_DISABLE_BOOST_ASSERT 1
17 # define BOOST_ASIO_DISABLE_BOOST_BIND 1
18 # define BOOST_ASIO_DISABLE_BOOST_CHRONO 1
19 # define BOOST_ASIO_DISABLE_BOOST_DATE_TIME 1
20 # define BOOST_ASIO_DISABLE_BOOST_LIMITS 1
21 # define BOOST_ASIO_DISABLE_BOOST_REGEX 1
22 # define BOOST_ASIO_DISABLE_BOOST_STATIC_CONSTANT 1
23 # define BOOST_ASIO_DISABLE_BOOST_THROW_EXCEPTION 1
24 # define BOOST_ASIO_DISABLE_BOOST_WORKAROUND 1
25 #else // defined(BOOST_ASIO_STANDALONE)
26 # include <boost/config.hpp>
27 # include <boost/version.hpp>
28 # define BOOST_ASIO_HAS_BOOST_CONFIG 1
29 #endif // defined(BOOST_ASIO_STANDALONE)
30 
31 // Default to a header-only implementation. The user must specifically request
32 // separate compilation by defining either BOOST_ASIO_SEPARATE_COMPILATION or
33 // BOOST_ASIO_DYN_LINK (as a DLL/shared library implies separate compilation).
34 #if !defined(BOOST_ASIO_HEADER_ONLY)
35 # if !defined(BOOST_ASIO_SEPARATE_COMPILATION)
36 #  if !defined(BOOST_ASIO_DYN_LINK)
37 #   define BOOST_ASIO_HEADER_ONLY 1
38 #  endif // !defined(BOOST_ASIO_DYN_LINK)
39 # endif // !defined(BOOST_ASIO_SEPARATE_COMPILATION)
40 #endif // !defined(BOOST_ASIO_HEADER_ONLY)
41 
42 #if defined(BOOST_ASIO_HEADER_ONLY)
43 # define BOOST_ASIO_DECL inline
44 #else // defined(BOOST_ASIO_HEADER_ONLY)
45 # if defined(_MSC_VER) || defined(__BORLANDC__) || defined(__CODEGEARC__)
46 // We need to import/export our code only if the user has specifically asked
47 // for it by defining BOOST_ASIO_DYN_LINK.
48 #  if defined(BOOST_ASIO_DYN_LINK)
49 // Export if this is our own source, otherwise import.
50 #   if defined(BOOST_ASIO_SOURCE)
51 #    define BOOST_ASIO_DECL __declspec(dllexport)
52 #   else // defined(BOOST_ASIO_SOURCE)
53 #    define BOOST_ASIO_DECL __declspec(dllimport)
54 #   endif // defined(BOOST_ASIO_SOURCE)
55 #  endif // defined(BOOST_ASIO_DYN_LINK)
56 # endif // defined(_MSC_VER) || defined(__BORLANDC__) || defined(__CODEGEARC__)
57 #endif // defined(BOOST_ASIO_HEADER_ONLY)
58 
59 // If BOOST_ASIO_DECL isn't defined yet define it now.
60 #if !defined(BOOST_ASIO_DECL)
61 # define BOOST_ASIO_DECL
62 #endif // !defined(BOOST_ASIO_DECL)
63 
64 // Microsoft Visual C++ detection.
65 #if !defined(BOOST_ASIO_MSVC)
66 # if defined(BOOST_ASIO_HAS_BOOST_CONFIG) && defined(BOOST_MSVC)
67 #  define BOOST_ASIO_MSVC BOOST_MSVC
68 # elif defined(_MSC_VER) && (defined(__INTELLISENSE__) \
69       || (!defined(__MWERKS__) && !defined(__EDG_VERSION__)))
70 #  define BOOST_ASIO_MSVC _MSC_VER
71 # endif // defined(BOOST_ASIO_HAS_BOOST_CONFIG) && defined(BOOST_MSVC)
72 #endif // !defined(BOOST_ASIO_MSVC)
73 
74 // Clang / libc++ detection.
75 #if defined(__clang__)
76 # if (__cplusplus >= 201103)
77 #  if __has_include(<__config>)
78 #   include <__config>
79 #   if defined(_LIBCPP_VERSION)
80 #    define BOOST_ASIO_HAS_CLANG_LIBCXX 1
81 #   endif // defined(_LIBCPP_VERSION)
82 #  endif // __has_include(<__config>)
83 # endif // (__cplusplus >= 201103)
84 #endif // defined(__clang__)
85 
86 // Android platform detection.
87 #if defined(__ANDROID__)
88 # include <android/api-level.h>
89 #endif // defined(__ANDROID__)
90 
91 // Support move construction and assignment on compilers known to allow it.
92 #if !defined(BOOST_ASIO_HAS_MOVE)
93 # if !defined(BOOST_ASIO_DISABLE_MOVE)
94 #  if defined(__clang__)
95 #   if __has_feature(__cxx_rvalue_references__)
96 #    define BOOST_ASIO_HAS_MOVE 1
97 #   endif // __has_feature(__cxx_rvalue_references__)
98 #  endif // defined(__clang__)
99 #  if defined(__GNUC__)
100 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 5)) || (__GNUC__ > 4)
101 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
102 #     define BOOST_ASIO_HAS_MOVE 1
103 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
104 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 5)) || (__GNUC__ > 4)
105 #  endif // defined(__GNUC__)
106 #  if defined(BOOST_ASIO_MSVC)
107 #   if (_MSC_VER >= 1700)
108 #    define BOOST_ASIO_HAS_MOVE 1
109 #   endif // (_MSC_VER >= 1700)
110 #  endif // defined(BOOST_ASIO_MSVC)
111 #  if defined(__INTEL_CXX11_MODE__)
112 #    if defined(__INTEL_COMPILER) && (__INTEL_COMPILER >= 1500)
113 #      define BOOST_ASIO_HAS_MOVE 1
114 #    endif // defined(__INTEL_COMPILER) && (__INTEL_COMPILER >= 1500)
115 #    if defined(__ICL) && (__ICL >= 1500)
116 #      define BOOST_ASIO_HAS_MOVE 1
117 #    endif // defined(__ICL) && (__ICL >= 1500)
118 #  endif // defined(__INTEL_CXX11_MODE__)
119 # endif // !defined(BOOST_ASIO_DISABLE_MOVE)
120 #endif // !defined(BOOST_ASIO_HAS_MOVE)
121 
122 // If BOOST_ASIO_MOVE_CAST isn't defined, and move support is available, define
123 // * BOOST_ASIO_MOVE_ARG,
124 // * BOOST_ASIO_NONDEDUCED_MOVE_ARG, and
125 // * BOOST_ASIO_MOVE_CAST
126 // to take advantage of rvalue references and perfect forwarding.
127 #if defined(BOOST_ASIO_HAS_MOVE) && !defined(BOOST_ASIO_MOVE_CAST)
128 # define BOOST_ASIO_MOVE_ARG(type) type&&
129 # define BOOST_ASIO_MOVE_ARG2(type1, type2) type1, type2&&
130 # define BOOST_ASIO_NONDEDUCED_MOVE_ARG(type) type&
131 # define BOOST_ASIO_MOVE_CAST(type) static_cast<type&&>
132 # define BOOST_ASIO_MOVE_CAST2(type1, type2) static_cast<type1, type2&&>
133 #endif // defined(BOOST_ASIO_HAS_MOVE) && !defined(BOOST_ASIO_MOVE_CAST)
134 
135 // If BOOST_ASIO_MOVE_CAST still isn't defined, default to a C++03-compatible
136 // implementation. Note that older g++ and MSVC versions don't like it when you
137 // pass a non-member function through a const reference, so for most compilers
138 // we'll play it safe and stick with the old approach of passing the handler by
139 // value.
140 #if !defined(BOOST_ASIO_MOVE_CAST)
141 # if defined(__GNUC__)
142 #  if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 1)) || (__GNUC__ > 4)
143 #   define BOOST_ASIO_MOVE_ARG(type) const type&
144 #  else // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 1)) || (__GNUC__ > 4)
145 #   define BOOST_ASIO_MOVE_ARG(type) type
146 #  endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 1)) || (__GNUC__ > 4)
147 # elif defined(BOOST_ASIO_MSVC)
148 #  if (_MSC_VER >= 1400)
149 #   define BOOST_ASIO_MOVE_ARG(type) const type&
150 #  else // (_MSC_VER >= 1400)
151 #   define BOOST_ASIO_MOVE_ARG(type) type
152 #  endif // (_MSC_VER >= 1400)
153 # else
154 #  define BOOST_ASIO_MOVE_ARG(type) type
155 # endif
156 # define BOOST_ASIO_NONDEDUCED_MOVE_ARG(type) const type&
157 # define BOOST_ASIO_MOVE_CAST(type) static_cast<const type&>
158 # define BOOST_ASIO_MOVE_CAST2(type1, type2) static_cast<const type1, type2&>
159 #endif // !defined(BOOST_ASIO_MOVE_CAST)
160 
161 // Support variadic templates on compilers known to allow it.
162 #if !defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
163 # if !defined(BOOST_ASIO_DISABLE_VARIADIC_TEMPLATES)
164 #  if defined(__clang__)
165 #   if __has_feature(__cxx_variadic_templates__)
166 #    define BOOST_ASIO_HAS_VARIADIC_TEMPLATES 1
167 #   endif // __has_feature(__cxx_variadic_templates__)
168 #  endif // defined(__clang__)
169 #  if defined(__GNUC__)
170 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 3)) || (__GNUC__ > 4)
171 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
172 #     define BOOST_ASIO_HAS_VARIADIC_TEMPLATES 1
173 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
174 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 3)) || (__GNUC__ > 4)
175 #  endif // defined(__GNUC__)
176 #  if defined(BOOST_ASIO_MSVC)
177 #   if (_MSC_VER >= 1900)
178 #    define BOOST_ASIO_HAS_VARIADIC_TEMPLATES 1
179 #   endif // (_MSC_VER >= 1900)
180 #  endif // defined(BOOST_ASIO_MSVC)
181 # endif // !defined(BOOST_ASIO_DISABLE_VARIADIC_TEMPLATES)
182 #endif // !defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
183 
184 // Support deleted functions on compilers known to allow it.
185 #if !defined(BOOST_ASIO_DELETED)
186 # if defined(__GNUC__)
187 #  if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
188 #   if defined(__GXX_EXPERIMENTAL_CXX0X__)
189 #    define BOOST_ASIO_DELETED = delete
190 #   endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
191 #  endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
192 # endif // defined(__GNUC__)
193 # if defined(__clang__)
194 #  if __has_feature(__cxx_deleted_functions__)
195 #   define BOOST_ASIO_DELETED = delete
196 #  endif // __has_feature(__cxx_deleted_functions__)
197 # endif // defined(__clang__)
198 # if defined(BOOST_ASIO_MSVC)
199 #  if (_MSC_VER >= 1900)
200 #   define BOOST_ASIO_DELETED = delete
201 #  endif // (_MSC_VER >= 1900)
202 # endif // defined(BOOST_ASIO_MSVC)
203 # if !defined(BOOST_ASIO_DELETED)
204 #  define BOOST_ASIO_DELETED
205 # endif // !defined(BOOST_ASIO_DELETED)
206 #endif // !defined(BOOST_ASIO_DELETED)
207 
208 // Support constexpr on compilers known to allow it.
209 #if !defined(BOOST_ASIO_HAS_CONSTEXPR)
210 # if !defined(BOOST_ASIO_DISABLE_CONSTEXPR)
211 #  if defined(__clang__)
212 #   if __has_feature(__cxx_constexpr__)
213 #    define BOOST_ASIO_HAS_CONSTEXPR 1
214 #   endif // __has_feature(__cxx_constexr__)
215 #  endif // defined(__clang__)
216 #  if defined(__GNUC__)
217 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
218 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
219 #     define BOOST_ASIO_HAS_CONSTEXPR 1
220 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
221 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
222 #  endif // defined(__GNUC__)
223 #  if defined(BOOST_ASIO_MSVC)
224 #   if (_MSC_VER >= 1900)
225 #    define BOOST_ASIO_HAS_CONSTEXPR 1
226 #   endif // (_MSC_VER >= 1900)
227 #  endif // defined(BOOST_ASIO_MSVC)
228 # endif // !defined(BOOST_ASIO_DISABLE_CONSTEXPR)
229 #endif // !defined(BOOST_ASIO_HAS_CONSTEXPR)
230 #if !defined(BOOST_ASIO_CONSTEXPR)
231 # if defined(BOOST_ASIO_HAS_CONSTEXPR)
232 #  define BOOST_ASIO_CONSTEXPR constexpr
233 # else // defined(BOOST_ASIO_HAS_CONSTEXPR)
234 #  define BOOST_ASIO_CONSTEXPR
235 # endif // defined(BOOST_ASIO_HAS_CONSTEXPR)
236 #endif // !defined(BOOST_ASIO_CONSTEXPR)
237 
238 // Support noexcept on compilers known to allow it.
239 #if !defined(BOOST_ASIO_NOEXCEPT)
240 # if !defined(BOOST_ASIO_DISABLE_NOEXCEPT)
241 #  if defined(BOOST_ASIO_HAS_BOOST_CONFIG) && (BOOST_VERSION >= 105300)
242 #   define BOOST_ASIO_NOEXCEPT BOOST_NOEXCEPT
243 #   define BOOST_ASIO_NOEXCEPT_OR_NOTHROW BOOST_NOEXCEPT_OR_NOTHROW
244 #  elif defined(__clang__)
245 #   if __has_feature(__cxx_noexcept__)
246 #    define BOOST_ASIO_NOEXCEPT noexcept(true)
247 #    define BOOST_ASIO_NOEXCEPT_OR_NOTHROW noexcept(true)
248 #   endif // __has_feature(__cxx_noexcept__)
249 #  elif defined(__GNUC__)
250 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
251 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
252 #      define BOOST_ASIO_NOEXCEPT noexcept(true)
253 #      define BOOST_ASIO_NOEXCEPT_OR_NOTHROW noexcept(true)
254 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
255 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
256 #  elif defined(BOOST_ASIO_MSVC)
257 #   if (_MSC_VER >= 1900)
258 #    define BOOST_ASIO_NOEXCEPT noexcept(true)
259 #    define BOOST_ASIO_NOEXCEPT_OR_NOTHROW noexcept(true)
260 #   endif // (_MSC_VER >= 1900)
261 #  endif // defined(BOOST_ASIO_MSVC)
262 # endif // !defined(BOOST_ASIO_DISABLE_NOEXCEPT)
263 # if !defined(BOOST_ASIO_NOEXCEPT)
264 #  define BOOST_ASIO_NOEXCEPT
265 # endif // !defined(BOOST_ASIO_NOEXCEPT)
266 # if !defined(BOOST_ASIO_NOEXCEPT_OR_NOTHROW)
267 #  define BOOST_ASIO_NOEXCEPT_OR_NOTHROW throw()
268 # endif // !defined(BOOST_ASIO_NOEXCEPT_OR_NOTHROW)
269 #endif // !defined(BOOST_ASIO_NOEXCEPT)
270 
271 // Support automatic type deduction on compilers known to support it.
272 #if !defined(BOOST_ASIO_HAS_DECLTYPE)
273 # if !defined(BOOST_ASIO_DISABLE_DECLTYPE)
274 #  if defined(__clang__)
275 #   if __has_feature(__cxx_decltype__)
276 #    define BOOST_ASIO_HAS_DECLTYPE 1
277 #   endif // __has_feature(__cxx_decltype__)
278 #  endif // defined(__clang__)
279 #  if defined(__GNUC__)
280 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
281 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
282 #     define BOOST_ASIO_HAS_DECLTYPE 1
283 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
284 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
285 #  endif // defined(__GNUC__)
286 #  if defined(BOOST_ASIO_MSVC)
287 #   if (_MSC_VER >= 1800)
288 #    define BOOST_ASIO_HAS_DECLTYPE 1
289 #   endif // (_MSC_VER >= 1800)
290 #  endif // defined(BOOST_ASIO_MSVC)
291 # endif // !defined(BOOST_ASIO_DISABLE_DECLTYPE)
292 #endif // !defined(BOOST_ASIO_HAS_DECLTYPE)
293 
294 // Support alias templates on compilers known to allow it.
295 #if !defined(BOOST_ASIO_HAS_ALIAS_TEMPLATES)
296 # if !defined(BOOST_ASIO_DISABLE_ALIAS_TEMPLATES)
297 #  if defined(__clang__)
298 #   if __has_feature(__cxx_alias_templates__)
299 #    define BOOST_ASIO_HAS_ALIAS_TEMPLATES 1
300 #   endif // __has_feature(__cxx_alias_templates__)
301 #  endif // defined(__clang__)
302 #  if defined(__GNUC__)
303 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
304 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
305 #     define BOOST_ASIO_HAS_ALIAS_TEMPLATES 1
306 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
307 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
308 #  endif // defined(__GNUC__)
309 #  if defined(BOOST_ASIO_MSVC)
310 #   if (_MSC_VER >= 1900)
311 #    define BOOST_ASIO_HAS_ALIAS_TEMPLATES 1
312 #   endif // (_MSC_VER >= 1900)
313 #  endif // defined(BOOST_ASIO_MSVC)
314 # endif // !defined(BOOST_ASIO_DISABLE_ALIAS_TEMPLATES)
315 #endif // !defined(BOOST_ASIO_HAS_ALIAS_TEMPLATES)
316 
317 // Support return type deduction on compilers known to allow it.
318 #if !defined(BOOST_ASIO_HAS_RETURN_TYPE_DEDUCTION)
319 # if !defined(BOOST_ASIO_DISABLE_RETURN_TYPE_DEDUCTION)
320 #  if defined(__clang__)
321 #   if __has_feature(__cxx_return_type_deduction__)
322 #    define BOOST_ASIO_HAS_RETURN_TYPE_DEDUCTION 1
323 #   endif // __has_feature(__cxx_alias_templates__)
324 #  elif (__cplusplus >= 201402)
325 #   define BOOST_ASIO_HAS_RETURN_TYPE_DEDUCTION 1
326 #  elif defined(__cpp_return_type_deduction)
327 #   if (__cpp_return_type_deduction >= 201304)
328 #    define BOOST_ASIO_HAS_RETURN_TYPE_DEDUCTION 1
329 #   endif // (__cpp_return_type_deduction >= 201304)
330 #  endif // defined(__cpp_return_type_deduction)
331 # endif // !defined(BOOST_ASIO_DISABLE_RETURN_TYPE_DEDUCTION)
332 #endif // !defined(BOOST_ASIO_HAS_RETURN_TYPE_DEDUCTION)
333 
334 // Support default function template arguments on compilers known to allow it.
335 #if !defined(BOOST_ASIO_HAS_DEFAULT_FUNCTION_TEMPLATE_ARGUMENTS)
336 # if !defined(BOOST_ASIO_DISABLE_DEFAULT_FUNCTION_TEMPLATE_ARGUMENTS)
337 #  if (__cplusplus >= 201103)
338 #   define BOOST_ASIO_HAS_DEFAULT_FUNCTION_TEMPLATE_ARGUMENTS 1
339 #  endif // (__cplusplus >= 201103)
340 # endif // !defined(BOOST_ASIO_DISABLE_DEFAULT_FUNCTION_TEMPLATE_ARGUMENTS)
341 #endif // !defined(BOOST_ASIO_HAS_DEFAULT_FUNCTION_TEMPLATE_ARGUMENTS)
342 
343 // Support concepts on compilers known to allow them.
344 #if !defined(BOOST_ASIO_HAS_CONCEPTS)
345 # if !defined(BOOST_ASIO_DISABLE_CONCEPTS)
346 #  if defined(__cpp_concepts)
347 #   define BOOST_ASIO_HAS_CONCEPTS 1
348 #   if (__cpp_concepts >= 201707)
349 #    define BOOST_ASIO_CONCEPT concept
350 #   else // (__cpp_concepts >= 201707)
351 #    define BOOST_ASIO_CONCEPT concept bool
352 #   endif // (__cpp_concepts >= 201707)
353 #  endif // defined(__cpp_concepts)
354 # endif // !defined(BOOST_ASIO_DISABLE_CONCEPTS)
355 #endif // !defined(BOOST_ASIO_HAS_CONCEPTS)
356 
357 // Standard library support for system errors.
358 # if !defined(BOOST_ASIO_DISABLE_STD_SYSTEM_ERROR)
359 #  if defined(__clang__)
360 #   if defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
361 #    define BOOST_ASIO_HAS_STD_SYSTEM_ERROR 1
362 #   elif (__cplusplus >= 201103)
363 #    if __has_include(<system_error>)
364 #     define BOOST_ASIO_HAS_STD_SYSTEM_ERROR 1
365 #    endif // __has_include(<system_error>)
366 #   endif // (__cplusplus >= 201103)
367 #  endif // defined(__clang__)
368 #  if defined(__GNUC__)
369 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
370 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
371 #     define BOOST_ASIO_HAS_STD_SYSTEM_ERROR 1
372 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
373 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
374 #  endif // defined(__GNUC__)
375 #  if defined(BOOST_ASIO_MSVC)
376 #   if (_MSC_VER >= 1700)
377 #    define BOOST_ASIO_HAS_STD_SYSTEM_ERROR 1
378 #   endif // (_MSC_VER >= 1700)
379 #  endif // defined(BOOST_ASIO_MSVC)
380 # endif // !defined(BOOST_ASIO_DISABLE_STD_SYSTEM_ERROR)
381 
382 // Compliant C++11 compilers put noexcept specifiers on error_category members.
383 #if !defined(BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT)
384 # if defined(BOOST_ASIO_HAS_BOOST_CONFIG) && (BOOST_VERSION >= 105300)
385 #  define BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT BOOST_NOEXCEPT
386 # elif defined(__clang__)
387 #  if __has_feature(__cxx_noexcept__)
388 #   define BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT noexcept(true)
389 #  endif // __has_feature(__cxx_noexcept__)
390 # elif defined(__GNUC__)
391 #  if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
392 #   if defined(__GXX_EXPERIMENTAL_CXX0X__)
393 #     define BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT noexcept(true)
394 #   endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
395 #  endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
396 # elif defined(BOOST_ASIO_MSVC)
397 #  if (_MSC_VER >= 1900)
398 #   define BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT noexcept(true)
399 #  endif // (_MSC_VER >= 1900)
400 # endif // defined(BOOST_ASIO_MSVC)
401 # if !defined(BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT)
402 #  define BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT
403 # endif // !defined(BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT)
404 #endif // !defined(BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT)
405 
406 // Standard library support for arrays.
407 #if !defined(BOOST_ASIO_HAS_STD_ARRAY)
408 # if !defined(BOOST_ASIO_DISABLE_STD_ARRAY)
409 #  if defined(__clang__)
410 #   if defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
411 #    define BOOST_ASIO_HAS_STD_ARRAY 1
412 #   elif (__cplusplus >= 201103)
413 #    if __has_include(<array>)
414 #     define BOOST_ASIO_HAS_STD_ARRAY 1
415 #    endif // __has_include(<array>)
416 #   endif // (__cplusplus >= 201103)
417 #  endif // defined(__clang__)
418 #  if defined(__GNUC__)
419 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 3)) || (__GNUC__ > 4)
420 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
421 #     define BOOST_ASIO_HAS_STD_ARRAY 1
422 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
423 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 3)) || (__GNUC__ > 4)
424 #  endif // defined(__GNUC__)
425 #  if defined(BOOST_ASIO_MSVC)
426 #   if (_MSC_VER >= 1600)
427 #    define BOOST_ASIO_HAS_STD_ARRAY 1
428 #   endif // (_MSC_VER >= 1600)
429 #  endif // defined(BOOST_ASIO_MSVC)
430 # endif // !defined(BOOST_ASIO_DISABLE_STD_ARRAY)
431 #endif // !defined(BOOST_ASIO_HAS_STD_ARRAY)
432 
433 // Standard library support for shared_ptr and weak_ptr.
434 #if !defined(BOOST_ASIO_HAS_STD_SHARED_PTR)
435 # if !defined(BOOST_ASIO_DISABLE_STD_SHARED_PTR)
436 #  if defined(__clang__)
437 #   if defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
438 #    define BOOST_ASIO_HAS_STD_SHARED_PTR 1
439 #   elif (__cplusplus >= 201103)
440 #    define BOOST_ASIO_HAS_STD_SHARED_PTR 1
441 #   endif // (__cplusplus >= 201103)
442 #  endif // defined(__clang__)
443 #  if defined(__GNUC__)
444 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 3)) || (__GNUC__ > 4)
445 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
446 #     define BOOST_ASIO_HAS_STD_SHARED_PTR 1
447 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
448 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 3)) || (__GNUC__ > 4)
449 #  endif // defined(__GNUC__)
450 #  if defined(BOOST_ASIO_MSVC)
451 #   if (_MSC_VER >= 1600)
452 #    define BOOST_ASIO_HAS_STD_SHARED_PTR 1
453 #   endif // (_MSC_VER >= 1600)
454 #  endif // defined(BOOST_ASIO_MSVC)
455 # endif // !defined(BOOST_ASIO_DISABLE_STD_SHARED_PTR)
456 #endif // !defined(BOOST_ASIO_HAS_STD_SHARED_PTR)
457 
458 // Standard library support for allocator_arg_t.
459 #if !defined(BOOST_ASIO_HAS_STD_ALLOCATOR_ARG)
460 # if !defined(BOOST_ASIO_DISABLE_STD_ALLOCATOR_ARG)
461 #  if defined(__clang__)
462 #   if defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
463 #    define BOOST_ASIO_HAS_STD_ALLOCATOR_ARG 1
464 #   elif (__cplusplus >= 201103)
465 #    define BOOST_ASIO_HAS_STD_ALLOCATOR_ARG 1
466 #   endif // (__cplusplus >= 201103)
467 #  endif // defined(__clang__)
468 #  if defined(__GNUC__)
469 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
470 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
471 #     define BOOST_ASIO_HAS_STD_ALLOCATOR_ARG 1
472 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
473 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
474 #  endif // defined(__GNUC__)
475 #  if defined(BOOST_ASIO_MSVC)
476 #   if (_MSC_VER >= 1600)
477 #    define BOOST_ASIO_HAS_STD_ALLOCATOR_ARG 1
478 #   endif // (_MSC_VER >= 1600)
479 #  endif // defined(BOOST_ASIO_MSVC)
480 # endif // !defined(BOOST_ASIO_DISABLE_STD_ALLOCATOR_ARG)
481 #endif // !defined(BOOST_ASIO_HAS_STD_ALLOCATOR_ARG)
482 
483 // Standard library support for atomic operations.
484 #if !defined(BOOST_ASIO_HAS_STD_ATOMIC)
485 # if !defined(BOOST_ASIO_DISABLE_STD_ATOMIC)
486 #  if defined(__clang__)
487 #   if defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
488 #    define BOOST_ASIO_HAS_STD_ATOMIC 1
489 #   elif (__cplusplus >= 201103)
490 #    if __has_include(<atomic>)
491 #     define BOOST_ASIO_HAS_STD_ATOMIC 1
492 #    endif // __has_include(<atomic>)
493 #   elif defined(__apple_build_version__) && defined(_LIBCPP_VERSION)
494 #    if (__clang_major__ >= 10)
495 #     if __has_include(<atomic>)
496 #      define BOOST_ASIO_HAS_STD_ATOMIC 1
497 #     endif // __has_include(<atomic>)
498 #    endif // (__clang_major__ >= 10)
499 #   endif /// defined(__apple_build_version__) && defined(_LIBCPP_VERSION)
500 #  endif // defined(__clang__)
501 #  if defined(__GNUC__)
502 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
503 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
504 #     define BOOST_ASIO_HAS_STD_ATOMIC 1
505 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
506 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
507 #  endif // defined(__GNUC__)
508 #  if defined(BOOST_ASIO_MSVC)
509 #   if (_MSC_VER >= 1700)
510 #    define BOOST_ASIO_HAS_STD_ATOMIC 1
511 #   endif // (_MSC_VER >= 1700)
512 #  endif // defined(BOOST_ASIO_MSVC)
513 # endif // !defined(BOOST_ASIO_DISABLE_STD_ATOMIC)
514 #endif // !defined(BOOST_ASIO_HAS_STD_ATOMIC)
515 
516 // Standard library support for chrono. Some standard libraries (such as the
517 // libstdc++ shipped with gcc 4.6) provide monotonic_clock as per early C++0x
518 // drafts, rather than the eventually standardised name of steady_clock.
519 #if !defined(BOOST_ASIO_HAS_STD_CHRONO)
520 # if !defined(BOOST_ASIO_DISABLE_STD_CHRONO)
521 #  if defined(__clang__)
522 #   if defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
523 #    define BOOST_ASIO_HAS_STD_CHRONO 1
524 #   elif (__cplusplus >= 201103)
525 #    if __has_include(<chrono>)
526 #     define BOOST_ASIO_HAS_STD_CHRONO 1
527 #    endif // __has_include(<chrono>)
528 #   endif // (__cplusplus >= 201103)
529 #  endif // defined(__clang__)
530 #  if defined(__GNUC__)
531 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
532 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
533 #     define BOOST_ASIO_HAS_STD_CHRONO 1
534 #     if ((__GNUC__ == 4) && (__GNUC_MINOR__ == 6))
535 #      define BOOST_ASIO_HAS_STD_CHRONO_MONOTONIC_CLOCK 1
536 #     endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ == 6))
537 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
538 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
539 #  endif // defined(__GNUC__)
540 #  if defined(BOOST_ASIO_MSVC)
541 #   if (_MSC_VER >= 1700)
542 #    define BOOST_ASIO_HAS_STD_CHRONO 1
543 #   endif // (_MSC_VER >= 1700)
544 #  endif // defined(BOOST_ASIO_MSVC)
545 # endif // !defined(BOOST_ASIO_DISABLE_STD_CHRONO)
546 #endif // !defined(BOOST_ASIO_HAS_STD_CHRONO)
547 
548 // Boost support for chrono.
549 #if !defined(BOOST_ASIO_HAS_BOOST_CHRONO)
550 # if !defined(BOOST_ASIO_DISABLE_BOOST_CHRONO)
551 #  if defined(BOOST_ASIO_HAS_BOOST_CONFIG) && (BOOST_VERSION >= 104700)
552 #   define BOOST_ASIO_HAS_BOOST_CHRONO 1
553 #  endif // defined(BOOST_ASIO_HAS_BOOST_CONFIG) && (BOOST_VERSION >= 104700)
554 # endif // !defined(BOOST_ASIO_DISABLE_BOOST_CHRONO)
555 #endif // !defined(BOOST_ASIO_HAS_BOOST_CHRONO)
556 
557 // Some form of chrono library is available.
558 #if !defined(BOOST_ASIO_HAS_CHRONO)
559 # if defined(BOOST_ASIO_HAS_STD_CHRONO) \
560     || defined(BOOST_ASIO_HAS_BOOST_CHRONO)
561 #  define BOOST_ASIO_HAS_CHRONO 1
562 # endif // defined(BOOST_ASIO_HAS_STD_CHRONO)
563         // || defined(BOOST_ASIO_HAS_BOOST_CHRONO)
564 #endif // !defined(BOOST_ASIO_HAS_CHRONO)
565 
566 // Boost support for the DateTime library.
567 #if !defined(BOOST_ASIO_HAS_BOOST_DATE_TIME)
568 # if !defined(BOOST_ASIO_DISABLE_BOOST_DATE_TIME)
569 #  define BOOST_ASIO_HAS_BOOST_DATE_TIME 1
570 # endif // !defined(BOOST_ASIO_DISABLE_BOOST_DATE_TIME)
571 #endif // !defined(BOOST_ASIO_HAS_BOOST_DATE_TIME)
572 
573 // Standard library support for addressof.
574 #if !defined(BOOST_ASIO_HAS_STD_ADDRESSOF)
575 # if !defined(BOOST_ASIO_DISABLE_STD_ADDRESSOF)
576 #  if defined(__clang__)
577 #   if defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
578 #    define BOOST_ASIO_HAS_STD_ADDRESSOF 1
579 #   elif (__cplusplus >= 201103)
580 #    define BOOST_ASIO_HAS_STD_ADDRESSOF 1
581 #   endif // (__cplusplus >= 201103)
582 #  endif // defined(__clang__)
583 #  if defined(__GNUC__)
584 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
585 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
586 #     define BOOST_ASIO_HAS_STD_ADDRESSOF 1
587 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
588 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
589 #  endif // defined(__GNUC__)
590 #  if defined(BOOST_ASIO_MSVC)
591 #   if (_MSC_VER >= 1700)
592 #    define BOOST_ASIO_HAS_STD_ADDRESSOF 1
593 #   endif // (_MSC_VER >= 1700)
594 #  endif // defined(BOOST_ASIO_MSVC)
595 # endif // !defined(BOOST_ASIO_DISABLE_STD_ADDRESSOF)
596 #endif // !defined(BOOST_ASIO_HAS_STD_ADDRESSOF)
597 
598 // Standard library support for the function class.
599 #if !defined(BOOST_ASIO_HAS_STD_FUNCTION)
600 # if !defined(BOOST_ASIO_DISABLE_STD_FUNCTION)
601 #  if defined(__clang__)
602 #   if defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
603 #    define BOOST_ASIO_HAS_STD_FUNCTION 1
604 #   elif (__cplusplus >= 201103)
605 #    define BOOST_ASIO_HAS_STD_FUNCTION 1
606 #   endif // (__cplusplus >= 201103)
607 #  endif // defined(__clang__)
608 #  if defined(__GNUC__)
609 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 5)) || (__GNUC__ > 4)
610 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
611 #     define BOOST_ASIO_HAS_STD_FUNCTION 1
612 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
613 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 5)) || (__GNUC__ > 4)
614 #  endif // defined(__GNUC__)
615 #  if defined(BOOST_ASIO_MSVC)
616 #   if (_MSC_VER >= 1700)
617 #    define BOOST_ASIO_HAS_STD_FUNCTION 1
618 #   endif // (_MSC_VER >= 1700)
619 #  endif // defined(BOOST_ASIO_MSVC)
620 # endif // !defined(BOOST_ASIO_DISABLE_STD_FUNCTION)
621 #endif // !defined(BOOST_ASIO_HAS_STD_FUNCTION)
622 
623 // Standard library support for type traits.
624 #if !defined(BOOST_ASIO_HAS_STD_TYPE_TRAITS)
625 # if !defined(BOOST_ASIO_DISABLE_STD_TYPE_TRAITS)
626 #  if defined(__clang__)
627 #   if defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
628 #    define BOOST_ASIO_HAS_STD_TYPE_TRAITS 1
629 #   elif (__cplusplus >= 201103)
630 #    if __has_include(<type_traits>)
631 #     define BOOST_ASIO_HAS_STD_TYPE_TRAITS 1
632 #    endif // __has_include(<type_traits>)
633 #   endif // (__cplusplus >= 201103)
634 #  endif // defined(__clang__)
635 #  if defined(__GNUC__)
636 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 5)) || (__GNUC__ > 4)
637 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
638 #     define BOOST_ASIO_HAS_STD_TYPE_TRAITS 1
639 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
640 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 5)) || (__GNUC__ > 4)
641 #  endif // defined(__GNUC__)
642 #  if defined(BOOST_ASIO_MSVC)
643 #   if (_MSC_VER >= 1700)
644 #    define BOOST_ASIO_HAS_STD_TYPE_TRAITS 1
645 #   endif // (_MSC_VER >= 1700)
646 #  endif // defined(BOOST_ASIO_MSVC)
647 # endif // !defined(BOOST_ASIO_DISABLE_STD_TYPE_TRAITS)
648 #endif // !defined(BOOST_ASIO_HAS_STD_TYPE_TRAITS)
649 
650 // Standard library support for the nullptr_t type.
651 #if !defined(BOOST_ASIO_HAS_NULLPTR)
652 # if !defined(BOOST_ASIO_DISABLE_NULLPTR)
653 #  if defined(__clang__)
654 #   if __has_feature(__cxx_nullptr__)
655 #    define BOOST_ASIO_HAS_NULLPTR 1
656 #   endif // __has_feature(__cxx_rvalue_references__)
657 #  elif defined(__GNUC__)
658 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
659 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
660 #     define BOOST_ASIO_HAS_NULLPTR 1
661 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
662 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
663 #  endif // defined(__GNUC__)
664 #  if defined(BOOST_ASIO_MSVC)
665 #   if (_MSC_VER >= 1700)
666 #    define BOOST_ASIO_HAS_NULLPTR 1
667 #   endif // (_MSC_VER >= 1700)
668 #  endif // defined(BOOST_ASIO_MSVC)
669 # endif // !defined(BOOST_ASIO_DISABLE_NULLPTR)
670 #endif // !defined(BOOST_ASIO_HAS_NULLPTR)
671 
672 // Standard library support for the C++11 allocator additions.
673 #if !defined(BOOST_ASIO_HAS_CXX11_ALLOCATORS)
674 # if !defined(BOOST_ASIO_DISABLE_CXX11_ALLOCATORS)
675 #  if defined(__clang__)
676 #   if defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
677 #    define BOOST_ASIO_HAS_CXX11_ALLOCATORS 1
678 #   elif (__cplusplus >= 201103)
679 #    define BOOST_ASIO_HAS_CXX11_ALLOCATORS 1
680 #   endif // (__cplusplus >= 201103)
681 #  elif defined(__GNUC__)
682 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
683 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
684 #     define BOOST_ASIO_HAS_CXX11_ALLOCATORS 1
685 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
686 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
687 #  endif // defined(__GNUC__)
688 #  if defined(BOOST_ASIO_MSVC)
689 #   if (_MSC_VER >= 1800)
690 #    define BOOST_ASIO_HAS_CXX11_ALLOCATORS 1
691 #   endif // (_MSC_VER >= 1800)
692 #  endif // defined(BOOST_ASIO_MSVC)
693 # endif // !defined(BOOST_ASIO_DISABLE_CXX11_ALLOCATORS)
694 #endif // !defined(BOOST_ASIO_HAS_CXX11_ALLOCATORS)
695 
696 // Standard library support for the cstdint header.
697 #if !defined(BOOST_ASIO_HAS_CSTDINT)
698 # if !defined(BOOST_ASIO_DISABLE_CSTDINT)
699 #  if defined(__clang__)
700 #   if defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
701 #    define BOOST_ASIO_HAS_CSTDINT 1
702 #   elif (__cplusplus >= 201103)
703 #    define BOOST_ASIO_HAS_CSTDINT 1
704 #   endif // (__cplusplus >= 201103)
705 #  endif // defined(__clang__)
706 #  if defined(__GNUC__)
707 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 5)) || (__GNUC__ > 4)
708 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
709 #     define BOOST_ASIO_HAS_CSTDINT 1
710 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
711 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 5)) || (__GNUC__ > 4)
712 #  endif // defined(__GNUC__)
713 #  if defined(BOOST_ASIO_MSVC)
714 #   if (_MSC_VER >= 1700)
715 #    define BOOST_ASIO_HAS_CSTDINT 1
716 #   endif // (_MSC_VER >= 1700)
717 #  endif // defined(BOOST_ASIO_MSVC)
718 # endif // !defined(BOOST_ASIO_DISABLE_CSTDINT)
719 #endif // !defined(BOOST_ASIO_HAS_CSTDINT)
720 
721 // Standard library support for the thread class.
722 #if !defined(BOOST_ASIO_HAS_STD_THREAD)
723 # if !defined(BOOST_ASIO_DISABLE_STD_THREAD)
724 #  if defined(__clang__)
725 #   if defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
726 #    define BOOST_ASIO_HAS_STD_THREAD 1
727 #   elif (__cplusplus >= 201103)
728 #    if __has_include(<thread>)
729 #     define BOOST_ASIO_HAS_STD_THREAD 1
730 #    endif // __has_include(<thread>)
731 #   endif // (__cplusplus >= 201103)
732 #  endif // defined(__clang__)
733 #  if defined(__GNUC__)
734 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
735 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
736 #     define BOOST_ASIO_HAS_STD_THREAD 1
737 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
738 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
739 #  endif // defined(__GNUC__)
740 #  if defined(BOOST_ASIO_MSVC)
741 #   if (_MSC_VER >= 1700)
742 #    define BOOST_ASIO_HAS_STD_THREAD 1
743 #   endif // (_MSC_VER >= 1700)
744 #  endif // defined(BOOST_ASIO_MSVC)
745 # endif // !defined(BOOST_ASIO_DISABLE_STD_THREAD)
746 #endif // !defined(BOOST_ASIO_HAS_STD_THREAD)
747 
748 // Standard library support for the mutex and condition variable classes.
749 #if !defined(BOOST_ASIO_HAS_STD_MUTEX_AND_CONDVAR)
750 # if !defined(BOOST_ASIO_DISABLE_STD_MUTEX_AND_CONDVAR)
751 #  if defined(__clang__)
752 #   if defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
753 #    define BOOST_ASIO_HAS_STD_MUTEX_AND_CONDVAR 1
754 #   elif (__cplusplus >= 201103)
755 #    if __has_include(<mutex>)
756 #     define BOOST_ASIO_HAS_STD_MUTEX_AND_CONDVAR 1
757 #    endif // __has_include(<mutex>)
758 #   endif // (__cplusplus >= 201103)
759 #  endif // defined(__clang__)
760 #  if defined(__GNUC__)
761 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
762 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
763 #     define BOOST_ASIO_HAS_STD_MUTEX_AND_CONDVAR 1
764 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
765 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
766 #  endif // defined(__GNUC__)
767 #  if defined(BOOST_ASIO_MSVC)
768 #   if (_MSC_VER >= 1700)
769 #    define BOOST_ASIO_HAS_STD_MUTEX_AND_CONDVAR 1
770 #   endif // (_MSC_VER >= 1700)
771 #  endif // defined(BOOST_ASIO_MSVC)
772 # endif // !defined(BOOST_ASIO_DISABLE_STD_MUTEX_AND_CONDVAR)
773 #endif // !defined(BOOST_ASIO_HAS_STD_MUTEX_AND_CONDVAR)
774 
775 // Standard library support for the call_once function.
776 #if !defined(BOOST_ASIO_HAS_STD_CALL_ONCE)
777 # if !defined(BOOST_ASIO_DISABLE_STD_CALL_ONCE)
778 #  if defined(__clang__)
779 #   if defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
780 #    define BOOST_ASIO_HAS_STD_CALL_ONCE 1
781 #   elif (__cplusplus >= 201103)
782 #    if __has_include(<mutex>)
783 #     define BOOST_ASIO_HAS_STD_CALL_ONCE 1
784 #    endif // __has_include(<mutex>)
785 #   endif // (__cplusplus >= 201103)
786 #  endif // defined(__clang__)
787 #  if defined(__GNUC__)
788 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
789 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
790 #     define BOOST_ASIO_HAS_STD_CALL_ONCE 1
791 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
792 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
793 #  endif // defined(__GNUC__)
794 #  if defined(BOOST_ASIO_MSVC)
795 #   if (_MSC_VER >= 1700)
796 #    define BOOST_ASIO_HAS_STD_CALL_ONCE 1
797 #   endif // (_MSC_VER >= 1700)
798 #  endif // defined(BOOST_ASIO_MSVC)
799 # endif // !defined(BOOST_ASIO_DISABLE_STD_CALL_ONCE)
800 #endif // !defined(BOOST_ASIO_HAS_STD_CALL_ONCE)
801 
802 // Standard library support for futures.
803 #if !defined(BOOST_ASIO_HAS_STD_FUTURE)
804 # if !defined(BOOST_ASIO_DISABLE_STD_FUTURE)
805 #  if defined(__clang__)
806 #   if defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
807 #    define BOOST_ASIO_HAS_STD_FUTURE 1
808 #   elif (__cplusplus >= 201103)
809 #    if __has_include(<future>)
810 #     define BOOST_ASIO_HAS_STD_FUTURE 1
811 #    endif // __has_include(<mutex>)
812 #   endif // (__cplusplus >= 201103)
813 #  endif // defined(__clang__)
814 #  if defined(__GNUC__)
815 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
816 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
817 #     define BOOST_ASIO_HAS_STD_FUTURE 1
818 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
819 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
820 #  endif // defined(__GNUC__)
821 #  if defined(BOOST_ASIO_MSVC)
822 #   if (_MSC_VER >= 1700)
823 #    define BOOST_ASIO_HAS_STD_FUTURE 1
824 #   endif // (_MSC_VER >= 1700)
825 #  endif // defined(BOOST_ASIO_MSVC)
826 # endif // !defined(BOOST_ASIO_DISABLE_STD_FUTURE)
827 #endif // !defined(BOOST_ASIO_HAS_STD_FUTURE)
828 
829 // Standard library support for std::string_view.
830 #if !defined(BOOST_ASIO_HAS_STD_STRING_VIEW)
831 # if !defined(BOOST_ASIO_DISABLE_STD_STRING_VIEW)
832 #  if defined(__clang__)
833 #   if defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
834 #    if (__cplusplus >= 201402)
835 #     if __has_include(<string_view>)
836 #      define BOOST_ASIO_HAS_STD_STRING_VIEW 1
837 #     endif // __has_include(<string_view>)
838 #    endif // (__cplusplus >= 201402)
839 #   else // defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
840 #    if (__cplusplus >= 201703)
841 #     if __has_include(<string_view>)
842 #      define BOOST_ASIO_HAS_STD_STRING_VIEW 1
843 #     endif // __has_include(<string_view>)
844 #    endif // (__cplusplus >= 201703)
845 #   endif // defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
846 #  elif defined(__GNUC__)
847 #   if (__GNUC__ >= 7)
848 #    if (__cplusplus >= 201703)
849 #     define BOOST_ASIO_HAS_STD_STRING_VIEW 1
850 #    endif // (__cplusplus >= 201703)
851 #   endif // (__GNUC__ >= 7)
852 #  elif defined(BOOST_ASIO_MSVC)
853 #   if (_MSC_VER >= 1910 && _MSVC_LANG >= 201703)
854 #    define BOOST_ASIO_HAS_STD_STRING_VIEW 1
855 #   endif // (_MSC_VER >= 1910 && _MSVC_LANG >= 201703)
856 #  endif // defined(BOOST_ASIO_MSVC)
857 # endif // !defined(BOOST_ASIO_DISABLE_STD_STRING_VIEW)
858 #endif // !defined(BOOST_ASIO_HAS_STD_STRING_VIEW)
859 
860 // Standard library support for std::experimental::string_view.
861 #if !defined(BOOST_ASIO_HAS_STD_EXPERIMENTAL_STRING_VIEW)
862 # if !defined(BOOST_ASIO_DISABLE_STD_EXPERIMENTAL_STRING_VIEW)
863 #  if defined(__clang__)
864 #   if defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
865 #    if (_LIBCPP_VERSION < 7000)
866 #     if (__cplusplus >= 201402)
867 #      if __has_include(<experimental/string_view>)
868 #       define BOOST_ASIO_HAS_STD_EXPERIMENTAL_STRING_VIEW 1
869 #      endif // __has_include(<experimental/string_view>)
870 #     endif // (__cplusplus >= 201402)
871 #    endif // (_LIBCPP_VERSION < 7000)
872 #   else // defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
873 #    if (__cplusplus >= 201402)
874 #     if __has_include(<experimental/string_view>)
875 #      define BOOST_ASIO_HAS_STD_EXPERIMENTAL_STRING_VIEW 1
876 #     endif // __has_include(<experimental/string_view>)
877 #    endif // (__cplusplus >= 201402)
878 #   endif // // defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
879 #  endif // defined(__clang__)
880 #  if defined(__GNUC__)
881 #   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 9)) || (__GNUC__ > 4)
882 #    if (__cplusplus >= 201402)
883 #     define BOOST_ASIO_HAS_STD_EXPERIMENTAL_STRING_VIEW 1
884 #    endif // (__cplusplus >= 201402)
885 #   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 9)) || (__GNUC__ > 4)
886 #  endif // defined(__GNUC__)
887 # endif // !defined(BOOST_ASIO_DISABLE_STD_EXPERIMENTAL_STRING_VIEW)
888 #endif // !defined(BOOST_ASIO_HAS_STD_EXPERIMENTAL_STRING_VIEW)
889 
890 // Standard library has a string_view that we can use.
891 #if !defined(BOOST_ASIO_HAS_STRING_VIEW)
892 # if !defined(BOOST_ASIO_DISABLE_STRING_VIEW)
893 #  if defined(BOOST_ASIO_HAS_STD_STRING_VIEW)
894 #   define BOOST_ASIO_HAS_STRING_VIEW 1
895 #  elif defined(BOOST_ASIO_HAS_STD_EXPERIMENTAL_STRING_VIEW)
896 #   define BOOST_ASIO_HAS_STRING_VIEW 1
897 #  endif // defined(BOOST_ASIO_HAS_STD_EXPERIMENTAL_STRING_VIEW)
898 # endif // !defined(BOOST_ASIO_DISABLE_STRING_VIEW)
899 #endif // !defined(BOOST_ASIO_HAS_STRING_VIEW)
900 
901 // Standard library support for iostream move construction and assignment.
902 #if !defined(BOOST_ASIO_HAS_STD_IOSTREAM_MOVE)
903 # if !defined(BOOST_ASIO_DISABLE_STD_IOSTREAM_MOVE)
904 #  if defined(__GNUC__)
905 #   if (__GNUC__ > 4)
906 #    if defined(__GXX_EXPERIMENTAL_CXX0X__)
907 #     define BOOST_ASIO_HAS_STD_IOSTREAM_MOVE 1
908 #    endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
909 #   endif // (__GNUC__ > 4)
910 #  endif // defined(__GNUC__)
911 #  if defined(BOOST_ASIO_MSVC)
912 #   if (_MSC_VER >= 1700)
913 #    define BOOST_ASIO_HAS_STD_IOSTREAM_MOVE 1
914 #   endif // (_MSC_VER >= 1700)
915 #  endif // defined(BOOST_ASIO_MSVC)
916 # endif // !defined(BOOST_ASIO_DISABLE_STD_IOSTREAM_MOVE)
917 #endif // !defined(BOOST_ASIO_HAS_STD_IOSTREAM_MOVE)
918 
919 // Standard library has invoke_result (which supersedes result_of).
920 #if !defined(BOOST_ASIO_HAS_STD_INVOKE_RESULT)
921 # if !defined(BOOST_ASIO_DISABLE_STD_INVOKE_RESULT)
922 #  if defined(BOOST_ASIO_MSVC)
923 #   if (_MSC_VER >= 1911 && _MSVC_LANG >= 201703)
924 #    define BOOST_ASIO_HAS_STD_INVOKE_RESULT 1
925 #   endif // (_MSC_VER >= 1911 && _MSVC_LANG >= 201703)
926 #  endif // defined(BOOST_ASIO_MSVC)
927 # endif // !defined(BOOST_ASIO_DISABLE_STD_INVOKE_RESULT)
928 #endif // !defined(BOOST_ASIO_HAS_STD_INVOKE_RESULT)
929 
930 // Windows App target. Windows but with a limited API.
931 #if !defined(BOOST_ASIO_WINDOWS_APP)
932 # if defined(_WIN32_WINNT) && (_WIN32_WINNT >= 0x0603)
933 #  include <winapifamily.h>
934 #  if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP) \
935    && !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
936 #   define BOOST_ASIO_WINDOWS_APP 1
937 #  endif // WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP)
938          // && !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
939 # endif // defined(_WIN32_WINNT) && (_WIN32_WINNT >= 0x0603)
940 #endif // !defined(BOOST_ASIO_WINDOWS_APP)
941 
942 // Legacy WinRT target. Windows App is preferred.
943 #if !defined(BOOST_ASIO_WINDOWS_RUNTIME)
944 # if !defined(BOOST_ASIO_WINDOWS_APP)
945 #  if defined(__cplusplus_winrt)
946 #   include <winapifamily.h>
947 #   if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP) \
948     && !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
949 #    define BOOST_ASIO_WINDOWS_RUNTIME 1
950 #   endif // WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP)
951           // && !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
952 #  endif // defined(__cplusplus_winrt)
953 # endif // !defined(BOOST_ASIO_WINDOWS_APP)
954 #endif // !defined(BOOST_ASIO_WINDOWS_RUNTIME)
955 
956 // Windows target. Excludes WinRT but includes Windows App targets.
957 #if !defined(BOOST_ASIO_WINDOWS)
958 # if !defined(BOOST_ASIO_WINDOWS_RUNTIME)
959 #  if defined(BOOST_ASIO_HAS_BOOST_CONFIG) && defined(BOOST_WINDOWS)
960 #   define BOOST_ASIO_WINDOWS 1
961 #  elif defined(WIN32) || defined(_WIN32) || defined(__WIN32__)
962 #   define BOOST_ASIO_WINDOWS 1
963 #  elif defined(BOOST_ASIO_WINDOWS_APP)
964 #   define BOOST_ASIO_WINDOWS 1
965 #  endif // defined(BOOST_ASIO_HAS_BOOST_CONFIG) && defined(BOOST_WINDOWS)
966 # endif // !defined(BOOST_ASIO_WINDOWS_RUNTIME)
967 #endif // !defined(BOOST_ASIO_WINDOWS)
968 
969 // Windows: target OS version.
970 #if defined(BOOST_ASIO_WINDOWS) || defined(__CYGWIN__)
971 # if !defined(_WIN32_WINNT) && !defined(_WIN32_WINDOWS)
972 #  if defined(_MSC_VER) || defined(__BORLANDC__)
973 #   pragma message( \
974   "Please define _WIN32_WINNT or _WIN32_WINDOWS appropriately. For example:\n"\
975   "- add -D_WIN32_WINNT=0x0601 to the compiler command line; or\n"\
976   "- add _WIN32_WINNT=0x0601 to your project's Preprocessor Definitions.\n"\
977   "Assuming _WIN32_WINNT=0x0601 (i.e. Windows 7 target).")
978 #  else // defined(_MSC_VER) || defined(__BORLANDC__)
979 #   warning Please define _WIN32_WINNT or _WIN32_WINDOWS appropriately.
980 #   warning For example, add -D_WIN32_WINNT=0x0601 to the compiler command line.
981 #   warning Assuming _WIN32_WINNT=0x0601 (i.e. Windows 7 target).
982 #  endif // defined(_MSC_VER) || defined(__BORLANDC__)
983 #  define _WIN32_WINNT 0x0601
984 # endif // !defined(_WIN32_WINNT) && !defined(_WIN32_WINDOWS)
985 # if defined(_MSC_VER)
986 #  if defined(_WIN32) && !defined(WIN32)
987 #   if !defined(_WINSOCK2API_)
988 #    define WIN32 // Needed for correct types in winsock2.h
989 #   else // !defined(_WINSOCK2API_)
990 #    error Please define the macro WIN32 in your compiler options
991 #   endif // !defined(_WINSOCK2API_)
992 #  endif // defined(_WIN32) && !defined(WIN32)
993 # endif // defined(_MSC_VER)
994 # if defined(__BORLANDC__)
995 #  if defined(__WIN32__) && !defined(WIN32)
996 #   if !defined(_WINSOCK2API_)
997 #    define WIN32 // Needed for correct types in winsock2.h
998 #   else // !defined(_WINSOCK2API_)
999 #    error Please define the macro WIN32 in your compiler options
1000 #   endif // !defined(_WINSOCK2API_)
1001 #  endif // defined(__WIN32__) && !defined(WIN32)
1002 # endif // defined(__BORLANDC__)
1003 # if defined(__CYGWIN__)
1004 #  if !defined(__USE_W32_SOCKETS)
1005 #   error You must add -D__USE_W32_SOCKETS to your compiler options.
1006 #  endif // !defined(__USE_W32_SOCKETS)
1007 # endif // defined(__CYGWIN__)
1008 #endif // defined(BOOST_ASIO_WINDOWS) || defined(__CYGWIN__)
1009 
1010 // Windows: minimise header inclusion.
1011 #if defined(BOOST_ASIO_WINDOWS) || defined(__CYGWIN__)
1012 # if !defined(BOOST_ASIO_NO_WIN32_LEAN_AND_MEAN)
1013 #  if !defined(WIN32_LEAN_AND_MEAN)
1014 #   define WIN32_LEAN_AND_MEAN
1015 #  endif // !defined(WIN32_LEAN_AND_MEAN)
1016 # endif // !defined(BOOST_ASIO_NO_WIN32_LEAN_AND_MEAN)
1017 #endif // defined(BOOST_ASIO_WINDOWS) || defined(__CYGWIN__)
1018 
1019 // Windows: suppress definition of "min" and "max" macros.
1020 #if defined(BOOST_ASIO_WINDOWS) || defined(__CYGWIN__)
1021 # if !defined(BOOST_ASIO_NO_NOMINMAX)
1022 #  if !defined(NOMINMAX)
1023 #   define NOMINMAX 1
1024 #  endif // !defined(NOMINMAX)
1025 # endif // !defined(BOOST_ASIO_NO_NOMINMAX)
1026 #endif // defined(BOOST_ASIO_WINDOWS) || defined(__CYGWIN__)
1027 
1028 // Windows: IO Completion Ports.
1029 #if !defined(BOOST_ASIO_HAS_IOCP)
1030 # if defined(BOOST_ASIO_WINDOWS) || defined(__CYGWIN__)
1031 #  if defined(_WIN32_WINNT) && (_WIN32_WINNT >= 0x0400)
1032 #   if !defined(UNDER_CE) && !defined(BOOST_ASIO_WINDOWS_APP)
1033 #    if !defined(BOOST_ASIO_DISABLE_IOCP)
1034 #     define BOOST_ASIO_HAS_IOCP 1
1035 #    endif // !defined(BOOST_ASIO_DISABLE_IOCP)
1036 #   endif // !defined(UNDER_CE) && !defined(BOOST_ASIO_WINDOWS_APP)
1037 #  endif // defined(_WIN32_WINNT) && (_WIN32_WINNT >= 0x0400)
1038 # endif // defined(BOOST_ASIO_WINDOWS) || defined(__CYGWIN__)
1039 #endif // !defined(BOOST_ASIO_HAS_IOCP)
1040 
1041 // On POSIX (and POSIX-like) platforms we need to include unistd.h in order to
1042 // get access to the various platform feature macros, e.g. to be able to test
1043 // for threads support.
1044 #if !defined(BOOST_ASIO_HAS_UNISTD_H)
1045 # if !defined(BOOST_ASIO_HAS_BOOST_CONFIG)
1046 #  if defined(unix) \
1047    || defined(__unix) \
1048    || defined(_XOPEN_SOURCE) \
1049    || defined(_POSIX_SOURCE) \
1050    || (defined(__MACH__) && defined(__APPLE__)) \
1051    || defined(__FreeBSD__) \
1052    || defined(__NetBSD__) \
1053    || defined(__OpenBSD__) \
1054    || defined(__linux__) \
1055    || defined(__HAIKU__)
1056 #   define BOOST_ASIO_HAS_UNISTD_H 1
1057 #  endif
1058 # endif // !defined(BOOST_ASIO_HAS_BOOST_CONFIG)
1059 #endif // !defined(BOOST_ASIO_HAS_UNISTD_H)
1060 #if defined(BOOST_ASIO_HAS_UNISTD_H)
1061 # include <unistd.h>
1062 #endif // defined(BOOST_ASIO_HAS_UNISTD_H)
1063 
1064 // Linux: epoll, eventfd and timerfd.
1065 #if defined(__linux__)
1066 # include <linux/version.h>
1067 # if !defined(BOOST_ASIO_HAS_EPOLL)
1068 #  if !defined(BOOST_ASIO_DISABLE_EPOLL)
1069 #   if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,45)
1070 #    define BOOST_ASIO_HAS_EPOLL 1
1071 #   endif // LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,45)
1072 #  endif // !defined(BOOST_ASIO_DISABLE_EPOLL)
1073 # endif // !defined(BOOST_ASIO_HAS_EPOLL)
1074 # if !defined(BOOST_ASIO_HAS_EVENTFD)
1075 #  if !defined(BOOST_ASIO_DISABLE_EVENTFD)
1076 #   if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22)
1077 #    define BOOST_ASIO_HAS_EVENTFD 1
1078 #   endif // LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22)
1079 #  endif // !defined(BOOST_ASIO_DISABLE_EVENTFD)
1080 # endif // !defined(BOOST_ASIO_HAS_EVENTFD)
1081 # if !defined(BOOST_ASIO_HAS_TIMERFD)
1082 #  if defined(BOOST_ASIO_HAS_EPOLL)
1083 #   if (__GLIBC__ > 2) || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 8)
1084 #    define BOOST_ASIO_HAS_TIMERFD 1
1085 #   endif // (__GLIBC__ > 2) || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 8)
1086 #  endif // defined(BOOST_ASIO_HAS_EPOLL)
1087 # endif // !defined(BOOST_ASIO_HAS_TIMERFD)
1088 #endif // defined(__linux__)
1089 
1090 // Mac OS X, FreeBSD, NetBSD, OpenBSD: kqueue.
1091 #if (defined(__MACH__) && defined(__APPLE__)) \
1092   || defined(__FreeBSD__) \
1093   || defined(__NetBSD__) \
1094   || defined(__OpenBSD__)
1095 # if !defined(BOOST_ASIO_HAS_KQUEUE)
1096 #  if !defined(BOOST_ASIO_DISABLE_KQUEUE)
1097 #   define BOOST_ASIO_HAS_KQUEUE 1
1098 #  endif // !defined(BOOST_ASIO_DISABLE_KQUEUE)
1099 # endif // !defined(BOOST_ASIO_HAS_KQUEUE)
1100 #endif // (defined(__MACH__) && defined(__APPLE__))
1101        //   || defined(__FreeBSD__)
1102        //   || defined(__NetBSD__)
1103        //   || defined(__OpenBSD__)
1104 
1105 // Solaris: /dev/poll.
1106 #if defined(__sun)
1107 # if !defined(BOOST_ASIO_HAS_DEV_POLL)
1108 #  if !defined(BOOST_ASIO_DISABLE_DEV_POLL)
1109 #   define BOOST_ASIO_HAS_DEV_POLL 1
1110 #  endif // !defined(BOOST_ASIO_DISABLE_DEV_POLL)
1111 # endif // !defined(BOOST_ASIO_HAS_DEV_POLL)
1112 #endif // defined(__sun)
1113 
1114 // Serial ports.
1115 #if !defined(BOOST_ASIO_HAS_SERIAL_PORT)
1116 # if defined(BOOST_ASIO_HAS_IOCP) \
1117   || !defined(BOOST_ASIO_WINDOWS) \
1118   && !defined(BOOST_ASIO_WINDOWS_RUNTIME) \
1119   && !defined(__CYGWIN__)
1120 #  if !defined(__SYMBIAN32__)
1121 #   if !defined(BOOST_ASIO_DISABLE_SERIAL_PORT)
1122 #    define BOOST_ASIO_HAS_SERIAL_PORT 1
1123 #   endif // !defined(BOOST_ASIO_DISABLE_SERIAL_PORT)
1124 #  endif // !defined(__SYMBIAN32__)
1125 # endif // defined(BOOST_ASIO_HAS_IOCP)
1126         //   || !defined(BOOST_ASIO_WINDOWS)
1127         //   && !defined(BOOST_ASIO_WINDOWS_RUNTIME)
1128         //   && !defined(__CYGWIN__)
1129 #endif // !defined(BOOST_ASIO_HAS_SERIAL_PORT)
1130 
1131 // Windows: stream handles.
1132 #if !defined(BOOST_ASIO_HAS_WINDOWS_STREAM_HANDLE)
1133 # if !defined(BOOST_ASIO_DISABLE_WINDOWS_STREAM_HANDLE)
1134 #  if defined(BOOST_ASIO_HAS_IOCP)
1135 #   define BOOST_ASIO_HAS_WINDOWS_STREAM_HANDLE 1
1136 #  endif // defined(BOOST_ASIO_HAS_IOCP)
1137 # endif // !defined(BOOST_ASIO_DISABLE_WINDOWS_STREAM_HANDLE)
1138 #endif // !defined(BOOST_ASIO_HAS_WINDOWS_STREAM_HANDLE)
1139 
1140 // Windows: random access handles.
1141 #if !defined(BOOST_ASIO_HAS_WINDOWS_RANDOM_ACCESS_HANDLE)
1142 # if !defined(BOOST_ASIO_DISABLE_WINDOWS_RANDOM_ACCESS_HANDLE)
1143 #  if defined(BOOST_ASIO_HAS_IOCP)
1144 #   define BOOST_ASIO_HAS_WINDOWS_RANDOM_ACCESS_HANDLE 1
1145 #  endif // defined(BOOST_ASIO_HAS_IOCP)
1146 # endif // !defined(BOOST_ASIO_DISABLE_WINDOWS_RANDOM_ACCESS_HANDLE)
1147 #endif // !defined(BOOST_ASIO_HAS_WINDOWS_RANDOM_ACCESS_HANDLE)
1148 
1149 // Windows: object handles.
1150 #if !defined(BOOST_ASIO_HAS_WINDOWS_OBJECT_HANDLE)
1151 # if !defined(BOOST_ASIO_DISABLE_WINDOWS_OBJECT_HANDLE)
1152 #  if defined(BOOST_ASIO_WINDOWS) || defined(__CYGWIN__)
1153 #   if !defined(UNDER_CE) && !defined(BOOST_ASIO_WINDOWS_APP)
1154 #    define BOOST_ASIO_HAS_WINDOWS_OBJECT_HANDLE 1
1155 #   endif // !defined(UNDER_CE) && !defined(BOOST_ASIO_WINDOWS_APP)
1156 #  endif // defined(BOOST_ASIO_WINDOWS) || defined(__CYGWIN__)
1157 # endif // !defined(BOOST_ASIO_DISABLE_WINDOWS_OBJECT_HANDLE)
1158 #endif // !defined(BOOST_ASIO_HAS_WINDOWS_OBJECT_HANDLE)
1159 
1160 // Windows: OVERLAPPED wrapper.
1161 #if !defined(BOOST_ASIO_HAS_WINDOWS_OVERLAPPED_PTR)
1162 # if !defined(BOOST_ASIO_DISABLE_WINDOWS_OVERLAPPED_PTR)
1163 #  if defined(BOOST_ASIO_HAS_IOCP)
1164 #   define BOOST_ASIO_HAS_WINDOWS_OVERLAPPED_PTR 1
1165 #  endif // defined(BOOST_ASIO_HAS_IOCP)
1166 # endif // !defined(BOOST_ASIO_DISABLE_WINDOWS_OVERLAPPED_PTR)
1167 #endif // !defined(BOOST_ASIO_HAS_WINDOWS_OVERLAPPED_PTR)
1168 
1169 // POSIX: stream-oriented file descriptors.
1170 #if !defined(BOOST_ASIO_HAS_POSIX_STREAM_DESCRIPTOR)
1171 # if !defined(BOOST_ASIO_DISABLE_POSIX_STREAM_DESCRIPTOR)
1172 #  if !defined(BOOST_ASIO_WINDOWS) \
1173   && !defined(BOOST_ASIO_WINDOWS_RUNTIME) \
1174   && !defined(__CYGWIN__)
1175 #   define BOOST_ASIO_HAS_POSIX_STREAM_DESCRIPTOR 1
1176 #  endif // !defined(BOOST_ASIO_WINDOWS)
1177          //   && !defined(BOOST_ASIO_WINDOWS_RUNTIME)
1178          //   && !defined(__CYGWIN__)
1179 # endif // !defined(BOOST_ASIO_DISABLE_POSIX_STREAM_DESCRIPTOR)
1180 #endif // !defined(BOOST_ASIO_HAS_POSIX_STREAM_DESCRIPTOR)
1181 
1182 // UNIX domain sockets.
1183 #if !defined(BOOST_ASIO_HAS_LOCAL_SOCKETS)
1184 # if !defined(BOOST_ASIO_DISABLE_LOCAL_SOCKETS)
1185 #  if !defined(BOOST_ASIO_WINDOWS) \
1186   && !defined(BOOST_ASIO_WINDOWS_RUNTIME) \
1187   && !defined(__CYGWIN__)
1188 #   define BOOST_ASIO_HAS_LOCAL_SOCKETS 1
1189 #  endif // !defined(BOOST_ASIO_WINDOWS)
1190          //   && !defined(BOOST_ASIO_WINDOWS_RUNTIME)
1191          //   && !defined(__CYGWIN__)
1192 # endif // !defined(BOOST_ASIO_DISABLE_LOCAL_SOCKETS)
1193 #endif // !defined(BOOST_ASIO_HAS_LOCAL_SOCKETS)
1194 
1195 // Can use sigaction() instead of signal().
1196 #if !defined(BOOST_ASIO_HAS_SIGACTION)
1197 # if !defined(BOOST_ASIO_DISABLE_SIGACTION)
1198 #  if !defined(BOOST_ASIO_WINDOWS) \
1199   && !defined(BOOST_ASIO_WINDOWS_RUNTIME) \
1200   && !defined(__CYGWIN__)
1201 #   define BOOST_ASIO_HAS_SIGACTION 1
1202 #  endif // !defined(BOOST_ASIO_WINDOWS)
1203          //   && !defined(BOOST_ASIO_WINDOWS_RUNTIME)
1204          //   && !defined(__CYGWIN__)
1205 # endif // !defined(BOOST_ASIO_DISABLE_SIGACTION)
1206 #endif // !defined(BOOST_ASIO_HAS_SIGACTION)
1207 
1208 // Can use signal().
1209 #if !defined(BOOST_ASIO_HAS_SIGNAL)
1210 # if !defined(BOOST_ASIO_DISABLE_SIGNAL)
1211 #  if !defined(UNDER_CE)
1212 #   define BOOST_ASIO_HAS_SIGNAL 1
1213 #  endif // !defined(UNDER_CE)
1214 # endif // !defined(BOOST_ASIO_DISABLE_SIGNAL)
1215 #endif // !defined(BOOST_ASIO_HAS_SIGNAL)
1216 
1217 // Can use getaddrinfo() and getnameinfo().
1218 #if !defined(BOOST_ASIO_HAS_GETADDRINFO)
1219 # if !defined(BOOST_ASIO_DISABLE_GETADDRINFO)
1220 #  if defined(BOOST_ASIO_WINDOWS) || defined(__CYGWIN__)
1221 #   if defined(_WIN32_WINNT) && (_WIN32_WINNT >= 0x0501)
1222 #    define BOOST_ASIO_HAS_GETADDRINFO 1
1223 #   elif defined(UNDER_CE)
1224 #    define BOOST_ASIO_HAS_GETADDRINFO 1
1225 #   endif // defined(UNDER_CE)
1226 #  elif defined(__MACH__) && defined(__APPLE__)
1227 #   if defined(__MAC_OS_X_VERSION_MIN_REQUIRED)
1228 #    if (__MAC_OS_X_VERSION_MIN_REQUIRED >= 1050)
1229 #     define BOOST_ASIO_HAS_GETADDRINFO 1
1230 #    endif // (__MAC_OS_X_VERSION_MIN_REQUIRED >= 1050)
1231 #   else // defined(__MAC_OS_X_VERSION_MIN_REQUIRED)
1232 #    define BOOST_ASIO_HAS_GETADDRINFO 1
1233 #   endif // defined(__MAC_OS_X_VERSION_MIN_REQUIRED)
1234 #  else // defined(__MACH__) && defined(__APPLE__)
1235 #   define BOOST_ASIO_HAS_GETADDRINFO 1
1236 #  endif // defined(__MACH__) && defined(__APPLE__)
1237 # endif // !defined(BOOST_ASIO_DISABLE_GETADDRINFO)
1238 #endif // !defined(BOOST_ASIO_HAS_GETADDRINFO)
1239 
1240 // Whether standard iostreams are disabled.
1241 #if !defined(BOOST_ASIO_NO_IOSTREAM)
1242 # if defined(BOOST_ASIO_HAS_BOOST_CONFIG) && defined(BOOST_NO_IOSTREAM)
1243 #  define BOOST_ASIO_NO_IOSTREAM 1
1244 # endif // !defined(BOOST_NO_IOSTREAM)
1245 #endif // !defined(BOOST_ASIO_NO_IOSTREAM)
1246 
1247 // Whether exception handling is disabled.
1248 #if !defined(BOOST_ASIO_NO_EXCEPTIONS)
1249 # if defined(BOOST_ASIO_HAS_BOOST_CONFIG) && defined(BOOST_NO_EXCEPTIONS)
1250 #  define BOOST_ASIO_NO_EXCEPTIONS 1
1251 # endif // !defined(BOOST_NO_EXCEPTIONS)
1252 #endif // !defined(BOOST_ASIO_NO_EXCEPTIONS)
1253 
1254 // Whether the typeid operator is supported.
1255 #if !defined(BOOST_ASIO_NO_TYPEID)
1256 # if defined(BOOST_ASIO_HAS_BOOST_CONFIG) && defined(BOOST_NO_TYPEID)
1257 #  define BOOST_ASIO_NO_TYPEID 1
1258 # endif // !defined(BOOST_NO_TYPEID)
1259 #endif // !defined(BOOST_ASIO_NO_TYPEID)
1260 
1261 // Threads.
1262 #if !defined(BOOST_ASIO_HAS_THREADS)
1263 # if !defined(BOOST_ASIO_DISABLE_THREADS)
1264 #  if defined(BOOST_ASIO_HAS_BOOST_CONFIG) && defined(BOOST_HAS_THREADS)
1265 #   define BOOST_ASIO_HAS_THREADS 1
1266 #  elif defined(__GNUC__) && !defined(__MINGW32__) \
1267      && !defined(linux) && !defined(__linux) && !defined(__linux__)
1268 #   define BOOST_ASIO_HAS_THREADS 1
1269 #  elif defined(_MT) || defined(__MT__)
1270 #   define BOOST_ASIO_HAS_THREADS 1
1271 #  elif defined(_REENTRANT)
1272 #   define BOOST_ASIO_HAS_THREADS 1
1273 #  elif defined(__APPLE__)
1274 #   define BOOST_ASIO_HAS_THREADS 1
1275 #  elif defined(__HAIKU__)
1276 #   define BOOST_ASIO_HAS_THREADS 1
1277 #  elif defined(_POSIX_THREADS) && (_POSIX_THREADS + 0 >= 0)
1278 #   define BOOST_ASIO_HAS_THREADS 1
1279 #  elif defined(_PTHREADS)
1280 #   define BOOST_ASIO_HAS_THREADS 1
1281 #  endif // defined(BOOST_ASIO_HAS_BOOST_CONFIG) && defined(BOOST_HAS_THREADS)
1282 # endif // !defined(BOOST_ASIO_DISABLE_THREADS)
1283 #endif // !defined(BOOST_ASIO_HAS_THREADS)
1284 
1285 // POSIX threads.
1286 #if !defined(BOOST_ASIO_HAS_PTHREADS)
1287 # if defined(BOOST_ASIO_HAS_THREADS)
1288 #  if defined(BOOST_ASIO_HAS_BOOST_CONFIG) && defined(BOOST_HAS_PTHREADS)
1289 #   define BOOST_ASIO_HAS_PTHREADS 1
1290 #  elif defined(_POSIX_THREADS) && (_POSIX_THREADS + 0 >= 0)
1291 #   define BOOST_ASIO_HAS_PTHREADS 1
1292 #  elif defined(__HAIKU__)
1293 #   define BOOST_ASIO_HAS_PTHREADS 1
1294 #  endif // defined(BOOST_ASIO_HAS_BOOST_CONFIG) && defined(BOOST_HAS_PTHREADS)
1295 # endif // defined(BOOST_ASIO_HAS_THREADS)
1296 #endif // !defined(BOOST_ASIO_HAS_PTHREADS)
1297 
1298 // Helper to prevent macro expansion.
1299 #define BOOST_ASIO_PREVENT_MACRO_SUBSTITUTION
1300 
1301 // Helper to define in-class constants.
1302 #if !defined(BOOST_ASIO_STATIC_CONSTANT)
1303 # if !defined(BOOST_ASIO_DISABLE_BOOST_STATIC_CONSTANT)
1304 #  define BOOST_ASIO_STATIC_CONSTANT(type, assignment) \
1305     BOOST_STATIC_CONSTANT(type, assignment)
1306 # else // !defined(BOOST_ASIO_DISABLE_BOOST_STATIC_CONSTANT)
1307 #  define BOOST_ASIO_STATIC_CONSTANT(type, assignment) \
1308     static const type assignment
1309 # endif // !defined(BOOST_ASIO_DISABLE_BOOST_STATIC_CONSTANT)
1310 #endif // !defined(BOOST_ASIO_STATIC_CONSTANT)
1311 
1312 // Boost array library.
1313 #if !defined(BOOST_ASIO_HAS_BOOST_ARRAY)
1314 # if !defined(BOOST_ASIO_DISABLE_BOOST_ARRAY)
1315 #  define BOOST_ASIO_HAS_BOOST_ARRAY 1
1316 # endif // !defined(BOOST_ASIO_DISABLE_BOOST_ARRAY)
1317 #endif // !defined(BOOST_ASIO_HAS_BOOST_ARRAY)
1318 
1319 // Boost assert macro.
1320 #if !defined(BOOST_ASIO_HAS_BOOST_ASSERT)
1321 # if !defined(BOOST_ASIO_DISABLE_BOOST_ASSERT)
1322 #  define BOOST_ASIO_HAS_BOOST_ASSERT 1
1323 # endif // !defined(BOOST_ASIO_DISABLE_BOOST_ASSERT)
1324 #endif // !defined(BOOST_ASIO_HAS_BOOST_ASSERT)
1325 
1326 // Boost limits header.
1327 #if !defined(BOOST_ASIO_HAS_BOOST_LIMITS)
1328 # if !defined(BOOST_ASIO_DISABLE_BOOST_LIMITS)
1329 #  define BOOST_ASIO_HAS_BOOST_LIMITS 1
1330 # endif // !defined(BOOST_ASIO_DISABLE_BOOST_LIMITS)
1331 #endif // !defined(BOOST_ASIO_HAS_BOOST_LIMITS)
1332 
1333 // Boost throw_exception function.
1334 #if !defined(BOOST_ASIO_HAS_BOOST_THROW_EXCEPTION)
1335 # if !defined(BOOST_ASIO_DISABLE_BOOST_THROW_EXCEPTION)
1336 #  define BOOST_ASIO_HAS_BOOST_THROW_EXCEPTION 1
1337 # endif // !defined(BOOST_ASIO_DISABLE_BOOST_THROW_EXCEPTION)
1338 #endif // !defined(BOOST_ASIO_HAS_BOOST_THROW_EXCEPTION)
1339 
1340 // Boost regex library.
1341 #if !defined(BOOST_ASIO_HAS_BOOST_REGEX)
1342 # if !defined(BOOST_ASIO_DISABLE_BOOST_REGEX)
1343 #  define BOOST_ASIO_HAS_BOOST_REGEX 1
1344 # endif // !defined(BOOST_ASIO_DISABLE_BOOST_REGEX)
1345 #endif // !defined(BOOST_ASIO_HAS_BOOST_REGEX)
1346 
1347 // Boost bind function.
1348 #if !defined(BOOST_ASIO_HAS_BOOST_BIND)
1349 # if !defined(BOOST_ASIO_DISABLE_BOOST_BIND)
1350 #  define BOOST_ASIO_HAS_BOOST_BIND 1
1351 # endif // !defined(BOOST_ASIO_DISABLE_BOOST_BIND)
1352 #endif // !defined(BOOST_ASIO_HAS_BOOST_BIND)
1353 
1354 // Boost's BOOST_WORKAROUND macro.
1355 #if !defined(BOOST_ASIO_HAS_BOOST_WORKAROUND)
1356 # if !defined(BOOST_ASIO_DISABLE_BOOST_WORKAROUND)
1357 #  define BOOST_ASIO_HAS_BOOST_WORKAROUND 1
1358 # endif // !defined(BOOST_ASIO_DISABLE_BOOST_WORKAROUND)
1359 #endif // !defined(BOOST_ASIO_HAS_BOOST_WORKAROUND)
1360 
1361 // Microsoft Visual C++'s secure C runtime library.
1362 #if !defined(BOOST_ASIO_HAS_SECURE_RTL)
1363 # if !defined(BOOST_ASIO_DISABLE_SECURE_RTL)
1364 #  if defined(BOOST_ASIO_MSVC) \
1365     && (BOOST_ASIO_MSVC >= 1400) \
1366     && !defined(UNDER_CE)
1367 #   define BOOST_ASIO_HAS_SECURE_RTL 1
1368 #  endif // defined(BOOST_ASIO_MSVC)
1369          // && (BOOST_ASIO_MSVC >= 1400)
1370          // && !defined(UNDER_CE)
1371 # endif // !defined(BOOST_ASIO_DISABLE_SECURE_RTL)
1372 #endif // !defined(BOOST_ASIO_HAS_SECURE_RTL)
1373 
1374 // Handler hooking. Disabled for ancient Borland C++ and gcc compilers.
1375 #if !defined(BOOST_ASIO_HAS_HANDLER_HOOKS)
1376 # if !defined(BOOST_ASIO_DISABLE_HANDLER_HOOKS)
1377 #  if defined(__GNUC__)
1378 #   if (__GNUC__ >= 3)
1379 #    define BOOST_ASIO_HAS_HANDLER_HOOKS 1
1380 #   endif // (__GNUC__ >= 3)
1381 #  elif !defined(__BORLANDC__)
1382 #   define BOOST_ASIO_HAS_HANDLER_HOOKS 1
1383 #  endif // !defined(__BORLANDC__)
1384 # endif // !defined(BOOST_ASIO_DISABLE_HANDLER_HOOKS)
1385 #endif // !defined(BOOST_ASIO_HAS_HANDLER_HOOKS)
1386 
1387 // Support for the __thread keyword extension.
1388 #if !defined(BOOST_ASIO_DISABLE_THREAD_KEYWORD_EXTENSION)
1389 # if defined(__linux__)
1390 #  if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
1391 #   if ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 3)) || (__GNUC__ > 3)
1392 #    if !defined(__INTEL_COMPILER) && !defined(__ICL) \
1393        && !(defined(__clang__) && defined(__ANDROID__))
1394 #     define BOOST_ASIO_HAS_THREAD_KEYWORD_EXTENSION 1
1395 #     define BOOST_ASIO_THREAD_KEYWORD __thread
1396 #    elif defined(__INTEL_COMPILER) && (__INTEL_COMPILER >= 1100)
1397 #     define BOOST_ASIO_HAS_THREAD_KEYWORD_EXTENSION 1
1398 #    endif // defined(__INTEL_COMPILER) && (__INTEL_COMPILER >= 1100)
1399            // && !(defined(__clang__) && defined(__ANDROID__))
1400 #   endif // ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 3)) || (__GNUC__ > 3)
1401 #  endif // defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
1402 # endif // defined(__linux__)
1403 # if defined(BOOST_ASIO_MSVC) && defined(BOOST_ASIO_WINDOWS_RUNTIME)
1404 #  if (_MSC_VER >= 1700)
1405 #   define BOOST_ASIO_HAS_THREAD_KEYWORD_EXTENSION 1
1406 #   define BOOST_ASIO_THREAD_KEYWORD __declspec(thread)
1407 #  endif // (_MSC_VER >= 1700)
1408 # endif // defined(BOOST_ASIO_MSVC) && defined(BOOST_ASIO_WINDOWS_RUNTIME)
1409 #endif // !defined(BOOST_ASIO_DISABLE_THREAD_KEYWORD_EXTENSION)
1410 #if !defined(BOOST_ASIO_THREAD_KEYWORD)
1411 # define BOOST_ASIO_THREAD_KEYWORD __thread
1412 #endif // !defined(BOOST_ASIO_THREAD_KEYWORD)
1413 
1414 // Support for POSIX ssize_t typedef.
1415 #if !defined(BOOST_ASIO_DISABLE_SSIZE_T)
1416 # if defined(__linux__) \
1417    || (defined(__MACH__) && defined(__APPLE__))
1418 #  define BOOST_ASIO_HAS_SSIZE_T 1
1419 # endif // defined(__linux__)
1420         //   || (defined(__MACH__) && defined(__APPLE__))
1421 #endif // !defined(BOOST_ASIO_DISABLE_SSIZE_T)
1422 
1423 // Helper macros to manage transition away from error_code return values.
1424 #if defined(BOOST_ASIO_NO_DEPRECATED)
1425 # define BOOST_ASIO_SYNC_OP_VOID void
1426 # define BOOST_ASIO_SYNC_OP_VOID_RETURN(e) return
1427 #else // defined(BOOST_ASIO_NO_DEPRECATED)
1428 # define BOOST_ASIO_SYNC_OP_VOID boost::system::error_code
1429 # define BOOST_ASIO_SYNC_OP_VOID_RETURN(e) return e
1430 #endif // defined(BOOST_ASIO_NO_DEPRECATED)
1431 
1432 // Newer gcc, clang need special treatment to suppress unused typedef warnings.
1433 #if defined(__clang__)
1434 # if defined(__apple_build_version__)
1435 #  if (__clang_major__ >= 7)
1436 #   define BOOST_ASIO_UNUSED_TYPEDEF __attribute__((__unused__))
1437 #  endif // (__clang_major__ >= 7)
1438 # elif ((__clang_major__ == 3) && (__clang_minor__ >= 6)) \
1439     || (__clang_major__ > 3)
1440 #  define BOOST_ASIO_UNUSED_TYPEDEF __attribute__((__unused__))
1441 # endif // ((__clang_major__ == 3) && (__clang_minor__ >= 6))
1442         //   || (__clang_major__ > 3)
1443 #elif defined(__GNUC__)
1444 # if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 8)) || (__GNUC__ > 4)
1445 #  define BOOST_ASIO_UNUSED_TYPEDEF __attribute__((__unused__))
1446 # endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 8)) || (__GNUC__ > 4)
1447 #endif // defined(__GNUC__)
1448 #if !defined(BOOST_ASIO_UNUSED_TYPEDEF)
1449 # define BOOST_ASIO_UNUSED_TYPEDEF
1450 #endif // !defined(BOOST_ASIO_UNUSED_TYPEDEF)
1451 
1452 // Some versions of gcc generate spurious warnings about unused variables.
1453 #if defined(__GNUC__)
1454 # if (__GNUC__ >= 4)
1455 #  define BOOST_ASIO_UNUSED_VARIABLE __attribute__((__unused__))
1456 # endif // (__GNUC__ >= 4)
1457 #endif // defined(__GNUC__)
1458 #if !defined(BOOST_ASIO_UNUSED_VARIABLE)
1459 # define BOOST_ASIO_UNUSED_VARIABLE
1460 #endif // !defined(BOOST_ASIO_UNUSED_VARIABLE)
1461 
1462 // Support co_await on compilers known to allow it.
1463 #if !defined(BOOST_ASIO_HAS_CO_AWAIT)
1464 # if !defined(BOOST_ASIO_DISABLE_CO_AWAIT)
1465 #  if defined(BOOST_ASIO_MSVC)
1466 #   if (_MSC_FULL_VER >= 190023506)
1467 #    if defined(_RESUMABLE_FUNCTIONS_SUPPORTED)
1468 #     define BOOST_ASIO_HAS_CO_AWAIT 1
1469 #    endif // defined(_RESUMABLE_FUNCTIONS_SUPPORTED)
1470 #   endif // (_MSC_FULL_VER >= 190023506)
1471 #  endif // defined(BOOST_ASIO_MSVC)
1472 # endif // !defined(BOOST_ASIO_DISABLE_CO_AWAIT)
1473 # if defined(__clang__)
1474 #  if (__cplusplus >= 201703) && (__cpp_coroutines >= 201703)
1475 #   if __has_include(<experimental/coroutine>)
1476 #    define BOOST_ASIO_HAS_CO_AWAIT 1
1477 #   endif // __has_include(<experimental/coroutine>)
1478 #  endif // (__cplusplus >= 201703) && (__cpp_coroutines >= 201703)
1479 # endif // defined(__clang__)
1480 #endif // !defined(BOOST_ASIO_HAS_CO_AWAIT)
1481 
1482 #endif // BOOST_ASIO_DETAIL_CONFIG_HPP
1483