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#if !__has_feature(cxx_exceptions) && !defined(BOOST_NO_EXCEPTIONS)
27# define BOOST_NO_EXCEPTIONS
28#endif
29
30#if !__has_feature(cxx_rtti) && !defined(BOOST_NO_RTTI)
31# define BOOST_NO_RTTI
32#endif
33
34#if !__has_feature(cxx_rtti) && !defined(BOOST_NO_TYPEID)
35# define BOOST_NO_TYPEID
36#endif
37
38#if defined(__int64) && !defined(__GNUC__)
39# define BOOST_HAS_MS_INT64
40#endif
41
42#define BOOST_HAS_NRVO
43
44// Branch prediction hints
45#if defined(__has_builtin)
46#if __has_builtin(__builtin_expect)
47#define BOOST_LIKELY(x) __builtin_expect(x, 1)
48#define BOOST_UNLIKELY(x) __builtin_expect(x, 0)
49#endif
50#endif
51
52// Clang supports "long long" in all compilation modes.
53#define BOOST_HAS_LONG_LONG
54
55//
56// We disable this if the compiler is really nvcc as it
57// doesn't actually support __int128 as of CUDA_VERSION=5000
58// even though it defines __SIZEOF_INT128__.
59// See https://svn.boost.org/trac/boost/ticket/10418
60// Only re-enable this for nvcc if you're absolutely sure
61// of the circumstances under which it's supported:
62//
63#if defined(__SIZEOF_INT128__) && !defined(__CUDACC__)
64# define BOOST_HAS_INT128
65#endif
66
67
68//
69// Dynamic shared object (DSO) and dynamic-link library (DLL) support
70//
71#if !defined(_WIN32) && !defined(__WIN32__) && !defined(WIN32)
72# define BOOST_SYMBOL_EXPORT __attribute__((__visibility__("default")))
73# define BOOST_SYMBOL_IMPORT
74# define BOOST_SYMBOL_VISIBLE __attribute__((__visibility__("default")))
75#endif
76
77//
78// The BOOST_FALLTHROUGH macro can be used to annotate implicit fall-through
79// between switch labels.
80//
81#if __cplusplus >= 201103L && defined(__has_warning)
82# if __has_feature(cxx_attributes) && __has_warning("-Wimplicit-fallthrough")
83# define BOOST_FALLTHROUGH [[clang::fallthrough]]
84# endif
85#endif
86
87#if !__has_feature(cxx_auto_type)
88# define BOOST_NO_CXX11_AUTO_DECLARATIONS
89# define BOOST_NO_CXX11_AUTO_MULTIDECLARATIONS
90#endif
91
92//
93// Currently clang on Windows using VC++ RTL does not support C++11's char16_t or char32_t
94//
95#if defined(_MSC_VER) || !(defined(__GXX_EXPERIMENTAL_CXX0X__) || __cplusplus >= 201103L)
96# define BOOST_NO_CXX11_CHAR16_T
97# define BOOST_NO_CXX11_CHAR32_T
98#endif
99
100#if !__has_feature(cxx_constexpr)
101# define BOOST_NO_CXX11_CONSTEXPR
102#endif
103
104#if !__has_feature(cxx_decltype)
105# define BOOST_NO_CXX11_DECLTYPE
106#endif
107
108#if !__has_feature(cxx_decltype_incomplete_return_types)
109# define BOOST_NO_CXX11_DECLTYPE_N3276
110#endif
111
112#if !__has_feature(cxx_defaulted_functions)
113# define BOOST_NO_CXX11_DEFAULTED_FUNCTIONS
114#endif
115
116#if !__has_feature(cxx_deleted_functions)
117# define BOOST_NO_CXX11_DELETED_FUNCTIONS
118#endif
119
120#if !__has_feature(cxx_explicit_conversions)
121# define BOOST_NO_CXX11_EXPLICIT_CONVERSION_OPERATORS
122#endif
123
124#if !__has_feature(cxx_default_function_template_args)
125# define BOOST_NO_CXX11_FUNCTION_TEMPLATE_DEFAULT_ARGS
126#endif
127
128#if !__has_feature(cxx_generalized_initializers)
129# define BOOST_NO_CXX11_HDR_INITIALIZER_LIST
130#endif
131
132#if !__has_feature(cxx_lambdas)
133# define BOOST_NO_CXX11_LAMBDAS
134#endif
135
136#if !__has_feature(cxx_local_type_template_args)
137# define BOOST_NO_CXX11_LOCAL_CLASS_TEMPLATE_PARAMETERS
138#endif
139
140#if !__has_feature(cxx_noexcept)
141# define BOOST_NO_CXX11_NOEXCEPT
142#endif
143
144#if !__has_feature(cxx_nullptr)
145# define BOOST_NO_CXX11_NULLPTR
146#endif
147
148#if !__has_feature(cxx_range_for)
149# define BOOST_NO_CXX11_RANGE_BASED_FOR
150#endif
151
152#if !__has_feature(cxx_raw_string_literals)
153# define BOOST_NO_CXX11_RAW_LITERALS
154#endif
155
156#if !__has_feature(cxx_reference_qualified_functions)
157# define BOOST_NO_CXX11_REF_QUALIFIERS
158#endif
159
160#if !__has_feature(cxx_generalized_initializers)
161# define BOOST_NO_CXX11_UNIFIED_INITIALIZATION_SYNTAX
162#endif
163
164#if !__has_feature(cxx_rvalue_references)
165# define BOOST_NO_CXX11_RVALUE_REFERENCES
166#endif
167
168#if !__has_feature(cxx_strong_enums)
169# define BOOST_NO_CXX11_SCOPED_ENUMS
170#endif
171
172#if !__has_feature(cxx_static_assert)
173# define BOOST_NO_CXX11_STATIC_ASSERT
174#endif
175
176#if !__has_feature(cxx_alias_templates)
177# define BOOST_NO_CXX11_TEMPLATE_ALIASES
178#endif
179
180#if !__has_feature(cxx_unicode_literals)
181# define BOOST_NO_CXX11_UNICODE_LITERALS
182#endif
183
184#if !__has_feature(cxx_variadic_templates)
185# define BOOST_NO_CXX11_VARIADIC_TEMPLATES
186#endif
187
188#if !__has_feature(cxx_user_literals)
189# define BOOST_NO_CXX11_USER_DEFINED_LITERALS
190#endif
191
192#if !__has_feature(cxx_alignas)
193# define BOOST_NO_CXX11_ALIGNAS
194#endif
195
196#if !__has_feature(cxx_trailing_return)
197# define BOOST_NO_CXX11_TRAILING_RESULT_TYPES
198#endif
199
200#if !__has_feature(cxx_inline_namespaces)
201# define BOOST_NO_CXX11_INLINE_NAMESPACES
202#endif
203
204#if !__has_feature(cxx_override_control)
205# define BOOST_NO_CXX11_FINAL
206#endif
207
208#if !(__has_feature(__cxx_binary_literals__) || __has_extension(__cxx_binary_literals__))
209# define BOOST_NO_CXX14_BINARY_LITERALS
210#endif
211
212#if !__has_feature(__cxx_decltype_auto__)
213# define BOOST_NO_CXX14_DECLTYPE_AUTO
214#endif
215
216#if !__has_feature(__cxx_aggregate_nsdmi__)
217# define BOOST_NO_CXX14_AGGREGATE_NSDMI
218#endif
219
220#if !__has_feature(__cxx_init_captures__)
221# define BOOST_NO_CXX14_INITIALIZED_LAMBDA_CAPTURES
222#endif
223
224#if !__has_feature(__cxx_generic_lambdas__)
225# define BOOST_NO_CXX14_GENERIC_LAMBDAS
226#endif
227
228// clang < 3.5 has a defect with dependent type, like following.
229//
230// template <class T>
231// constexpr typename enable_if<pred<T> >::type foo(T &)
232// { } // error: no return statement in constexpr function
233//
234// This issue also affects C++11 mode, but C++11 constexpr requires return stmt.
235// Therefore we don't care such case.
236//
237// Note that we can't check Clang version directly as the numbering system changes depending who's
238// creating the Clang release (see https://github.com/boostorg/config/pull/39#issuecomment-59927873)
239// so instead verify that we have a feature that was introduced at the same time as working C++14
240// constexpr (generic lambda's in this case):
241//
242#if !__has_feature(__cxx_generic_lambdas__) || !__has_feature(__cxx_relaxed_constexpr__)
243# define BOOST_NO_CXX14_CONSTEXPR
244#endif
245
246#if !__has_feature(__cxx_return_type_deduction__)
247# define BOOST_NO_CXX14_RETURN_TYPE_DEDUCTION
248#endif
249
250#if !__has_feature(__cxx_variable_templates__)
251# define BOOST_NO_CXX14_VARIABLE_TEMPLATES
252#endif
253
254#if __cplusplus < 201400
255// All versions with __cplusplus above this value seem to support this:
256# define BOOST_NO_CXX14_DIGIT_SEPARATORS
257#endif
258
259
260// Unused attribute:
261#if defined(__GNUC__) && (__GNUC__ >= 4)
262# define BOOST_ATTRIBUTE_UNUSED __attribute__((unused))
263#endif
264
265#ifndef BOOST_COMPILER
266# define BOOST_COMPILER "Clang version " __clang_version__
267#endif
268
269// Macro used to identify the Clang compiler.
270#define BOOST_CLANG 1
271
272