1// (C) Copyright Douglas Gregor 2010
2//
3// Use, modification and distribution are subject to the
4// Boost Software License, Version 1.0. (See accompanying file
5// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6
7// See http://www.boost.org for most recent version.
8
9// Clang compiler setup.
10
11#define BOOST_HAS_PRAGMA_ONCE
12
13// Detecting `-fms-extension` compiler flag assuming that _MSC_VER defined when that flag is used.
14#if defined (_MSC_VER) && (__clang_major__ > 3 || (__clang_major__ == 3 && __clang_minor__ >= 4))
15# define BOOST_HAS_PRAGMA_DETECT_MISMATCH
16#endif
17
18// When compiling with clang before __has_extension was defined,
19// even if one writes 'defined(__has_extension) && __has_extension(xxx)',
20// clang reports a compiler error. So the only workaround found is:
21
22#ifndef __has_extension
23#define __has_extension __has_feature
24#endif
25
26#ifndef __has_attribute
27#define __has_attribute(x) 0
28#endif
29
30#ifndef __has_cpp_attribute
31#define __has_cpp_attribute(x) 0
32#endif
33
34#if !__has_feature(cxx_exceptions) && !defined(BOOST_NO_EXCEPTIONS)
35# define BOOST_NO_EXCEPTIONS
36#endif
37
38#if !__has_feature(cxx_rtti) && !defined(BOOST_NO_RTTI)
39# define BOOST_NO_RTTI
40#endif
41
42#if !__has_feature(cxx_rtti) && !defined(BOOST_NO_TYPEID)
43# define BOOST_NO_TYPEID
44#endif
45
46#if !__has_feature(cxx_thread_local)
47# define BOOST_NO_CXX11_THREAD_LOCAL
48#endif
49
50#ifdef __is_identifier
51#if !__is_identifier(__int64) && !defined(__GNUC__)
52# define BOOST_HAS_MS_INT64
53#endif
54#endif
55
56#if __has_include(<stdint.h>)
57# define BOOST_HAS_STDINT_H
58#endif
59
60
61#define BOOST_HAS_NRVO
62
63// Branch prediction hints
64#if !defined (__c2__) && defined(__has_builtin)
65#if __has_builtin(__builtin_expect)
66#define BOOST_LIKELY(x) __builtin_expect(x, 1)
67#define BOOST_UNLIKELY(x) __builtin_expect(x, 0)
68#endif
69#endif
70
71// Clang supports "long long" in all compilation modes.
72#define BOOST_HAS_LONG_LONG
73
74//
75// We disable this if the compiler is really nvcc with C++03 as it
76// doesn't actually support __int128 as of CUDA_VERSION=7500
77// even though it defines __SIZEOF_INT128__.
78// See https://svn.boost.org/trac/boost/ticket/10418
79// https://svn.boost.org/trac/boost/ticket/11852
80// Only re-enable this for nvcc if you're absolutely sure
81// of the circumstances under which it's supported.
82// Similarly __SIZEOF_INT128__ is defined when targetting msvc
83// compatibility even though the required support functions are absent.
84//
85#if defined(__CUDACC__)
86# if defined(BOOST_GCC_CXX11)
87# define BOOST_NVCC_CXX11
88# else
89# define BOOST_NVCC_CXX03
90# endif
91#endif
92
93#if defined(__SIZEOF_INT128__) && !defined(BOOST_NVCC_CXX03) && !defined(_MSC_VER)
94# define BOOST_HAS_INT128
95#endif
96
97
98//
99// Dynamic shared object (DSO) and dynamic-link library (DLL) support
100//
101#if !defined(_WIN32) && !defined(__WIN32__) && !defined(WIN32)
102# define BOOST_SYMBOL_EXPORT __attribute__((__visibility__("default")))
103# define BOOST_SYMBOL_IMPORT
104# define BOOST_SYMBOL_VISIBLE __attribute__((__visibility__("default")))
105#endif
106
107//
108// The BOOST_FALLTHROUGH macro can be used to annotate implicit fall-through
109// between switch labels.
110//
111#if __cplusplus >= 201103L && defined(__has_warning)
112# if __has_feature(cxx_attributes) && __has_warning("-Wimplicit-fallthrough")
113# define BOOST_FALLTHROUGH [[clang::fallthrough]]
114# endif
115#endif
116
117#if !__has_feature(cxx_auto_type)
118# define BOOST_NO_CXX11_AUTO_DECLARATIONS
119# define BOOST_NO_CXX11_AUTO_MULTIDECLARATIONS
120#endif
121
122//
123// Currently clang on Windows using VC++ RTL does not support C++11's char16_t or char32_t
124//
125#if (defined(_MSC_VER) && (_MSC_VER < 1900)) || !(defined(__GXX_EXPERIMENTAL_CXX0X__) || __cplusplus >= 201103L)
126# define BOOST_NO_CXX11_CHAR16_T
127# define BOOST_NO_CXX11_CHAR32_T
128#endif
129
130#if defined(_MSC_VER) && (_MSC_VER >= 1800) && !defined(__GNUC__)
131#define BOOST_HAS_EXPM1
132#define BOOST_HAS_LOG1P
133#endif
134
135#if !__has_feature(cxx_constexpr)
136# define BOOST_NO_CXX11_CONSTEXPR
137#endif
138
139#if !__has_feature(cxx_decltype)
140# define BOOST_NO_CXX11_DECLTYPE
141#endif
142
143#if !__has_feature(cxx_decltype_incomplete_return_types)
144# define BOOST_NO_CXX11_DECLTYPE_N3276
145#endif
146
147#if !__has_feature(cxx_defaulted_functions)
148# define BOOST_NO_CXX11_DEFAULTED_FUNCTIONS
149#endif
150
151#if !__has_feature(cxx_deleted_functions)
152# define BOOST_NO_CXX11_DELETED_FUNCTIONS
153#endif
154
155#if !__has_feature(cxx_explicit_conversions)
156# define BOOST_NO_CXX11_EXPLICIT_CONVERSION_OPERATORS
157#endif
158
159#if !__has_feature(cxx_default_function_template_args)
160# define BOOST_NO_CXX11_FUNCTION_TEMPLATE_DEFAULT_ARGS
161#endif
162
163#if !__has_feature(cxx_generalized_initializers)
164# define BOOST_NO_CXX11_HDR_INITIALIZER_LIST
165#endif
166
167#if !__has_feature(cxx_lambdas)
168# define BOOST_NO_CXX11_LAMBDAS
169#endif
170
171#if !__has_feature(cxx_local_type_template_args)
172# define BOOST_NO_CXX11_LOCAL_CLASS_TEMPLATE_PARAMETERS
173#endif
174
175#if !__has_feature(cxx_noexcept)
176# define BOOST_NO_CXX11_NOEXCEPT
177#endif
178
179#if !__has_feature(cxx_nullptr)
180# define BOOST_NO_CXX11_NULLPTR
181#endif
182
183#if !__has_feature(cxx_range_for)
184# define BOOST_NO_CXX11_RANGE_BASED_FOR
185#endif
186
187#if !__has_feature(cxx_raw_string_literals)
188# define BOOST_NO_CXX11_RAW_LITERALS
189#endif
190
191#if !__has_feature(cxx_reference_qualified_functions)
192# define BOOST_NO_CXX11_REF_QUALIFIERS
193#endif
194
195#if !__has_feature(cxx_generalized_initializers)
196# define BOOST_NO_CXX11_UNIFIED_INITIALIZATION_SYNTAX
197#endif
198
199#if !__has_feature(cxx_rvalue_references)
200# define BOOST_NO_CXX11_RVALUE_REFERENCES
201#endif
202
203#if !__has_feature(cxx_strong_enums)
204# define BOOST_NO_CXX11_SCOPED_ENUMS
205#endif
206
207#if !__has_feature(cxx_static_assert)
208# define BOOST_NO_CXX11_STATIC_ASSERT
209#endif
210
211#if !__has_feature(cxx_alias_templates)
212# define BOOST_NO_CXX11_TEMPLATE_ALIASES
213#endif
214
215#if !__has_feature(cxx_unicode_literals)
216# define BOOST_NO_CXX11_UNICODE_LITERALS
217#endif
218
219#if !__has_feature(cxx_variadic_templates)
220# define BOOST_NO_CXX11_VARIADIC_TEMPLATES
221#endif
222
223#if !__has_feature(cxx_user_literals)
224# define BOOST_NO_CXX11_USER_DEFINED_LITERALS
225#endif
226
227#if !__has_feature(cxx_alignas)
228# define BOOST_NO_CXX11_ALIGNAS
229#endif
230
231#if !__has_feature(cxx_trailing_return)
232# define BOOST_NO_CXX11_TRAILING_RESULT_TYPES
233#endif
234
235#if !__has_feature(cxx_inline_namespaces)
236# define BOOST_NO_CXX11_INLINE_NAMESPACES
237#endif
238
239#if !__has_feature(cxx_override_control)
240# define BOOST_NO_CXX11_FINAL
241#endif
242
243#if !(__has_feature(__cxx_binary_literals__) || __has_extension(__cxx_binary_literals__))
244# define BOOST_NO_CXX14_BINARY_LITERALS
245#endif
246
247#if !__has_feature(__cxx_decltype_auto__)
248# define BOOST_NO_CXX14_DECLTYPE_AUTO
249#endif
250
251#if !__has_feature(__cxx_aggregate_nsdmi__)
252# define BOOST_NO_CXX14_AGGREGATE_NSDMI
253#endif
254
255#if !__has_feature(__cxx_init_captures__)
256# define BOOST_NO_CXX14_INITIALIZED_LAMBDA_CAPTURES
257#endif
258
259#if !__has_feature(__cxx_generic_lambdas__)
260# define BOOST_NO_CXX14_GENERIC_LAMBDAS
261#endif
262
263// clang < 3.5 has a defect with dependent type, like following.
264//
265// template <class T>
266// constexpr typename enable_if<pred<T> >::type foo(T &)
267// { } // error: no return statement in constexpr function
268//
269// This issue also affects C++11 mode, but C++11 constexpr requires return stmt.
270// Therefore we don't care such case.
271//
272// Note that we can't check Clang version directly as the numbering system changes depending who's
273// creating the Clang release (see https://github.com/boostorg/config/pull/39#issuecomment-59927873)
274// so instead verify that we have a feature that was introduced at the same time as working C++14
275// constexpr (generic lambda's in this case):
276//
277#if !__has_feature(__cxx_generic_lambdas__) || !__has_feature(__cxx_relaxed_constexpr__)
278# define BOOST_NO_CXX14_CONSTEXPR
279#endif
280
281#if !__has_feature(__cxx_return_type_deduction__)
282# define BOOST_NO_CXX14_RETURN_TYPE_DEDUCTION
283#endif
284
285#if !__has_feature(__cxx_variable_templates__)
286# define BOOST_NO_CXX14_VARIABLE_TEMPLATES
287#endif
288
289#if !defined(__cpp_structured_bindings) || (__cpp_structured_bindings < 201606)
290# define BOOST_NO_CXX17_STRUCTURED_BINDINGS
291#endif
292
293// Clang 3.9+ in c++1z
294#if !__has_cpp_attribute(fallthrough) || __cplusplus < 201406L
295# define BOOST_NO_CXX17_INLINE_VARIABLES
296# define BOOST_NO_CXX17_FOLD_EXPRESSIONS
297#endif
298
299#if __cplusplus < 201103L
300#define BOOST_NO_CXX11_SFINAE_EXPR
301#endif
302
303#if __cplusplus < 201400
304// All versions with __cplusplus above this value seem to support this:
305# define BOOST_NO_CXX14_DIGIT_SEPARATORS
306#endif
307//
308// __builtin_unreachable:
309#if defined(__has_builtin) && __has_builtin(__builtin_unreachable)
310#define BOOST_UNREACHABLE_RETURN(x) __builtin_unreachable();
311#endif
312
313#if (__clang_major__ == 3) && (__clang_minor__ == 0)
314// Apparently a clang bug:
315# define BOOST_NO_CXX11_FIXED_LENGTH_VARIADIC_TEMPLATE_EXPANSION_PACKS
316#endif
317
318// Clang has supported the 'unused' attribute since the first release.
319#define BOOST_ATTRIBUTE_UNUSED __attribute__((__unused__))
320
321#ifndef BOOST_COMPILER
322# define BOOST_COMPILER "Clang version " __clang_version__
323#endif
324
325// Macro used to identify the Clang compiler.
326#define BOOST_CLANG 1
327
328