2 * Copyright 2016 Facebook, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
23 #include <folly/portability/Config.h>
25 #include <folly/CPortability.h>
27 #if FOLLY_HAVE_SCHED_H
31 // Unaligned loads and stores
33 #if FOLLY_HAVE_UNALIGNED_ACCESS
34 constexpr bool kHasUnalignedAccess = true;
36 constexpr bool kHasUnalignedAccess = false;
40 // compiler specific attribute translation
41 // msvc should come first, so if clang is in msvc mode it gets the right defines
43 #if defined(__clang__) || defined(__GNUC__)
44 # define FOLLY_ALIGNED(size) __attribute__((__aligned__(size)))
45 #elif defined(_MSC_VER)
46 # define FOLLY_ALIGNED(size) __declspec(align(size))
48 # error Cannot define FOLLY_ALIGNED on this platform
50 #define FOLLY_ALIGNED_MAX FOLLY_ALIGNED(alignof(std::max_align_t))
52 // NOTE: this will only do checking in msvc with versions that support /analyze
54 # ifdef _USE_ATTRIBUTES_FOR_SAL
55 # undef _USE_ATTRIBUTES_FOR_SAL
58 # define _USE_ATTRIBUTES_FOR_SAL 1
60 # define FOLLY_PRINTF_FORMAT _Printf_format_string_
61 # define FOLLY_PRINTF_FORMAT_ATTR(format_param, dots_param) /**/
63 # define FOLLY_PRINTF_FORMAT /**/
64 # define FOLLY_PRINTF_FORMAT_ATTR(format_param, dots_param) \
65 __attribute__((__format__(__printf__, format_param, dots_param)))
69 #if defined(__clang__) || defined(__GNUC__)
70 # define FOLLY_DEPRECATED(msg) __attribute__((__deprecated__(msg)))
71 #elif defined(_MSC_VER)
72 # define FOLLY_DEPRECATED(msg) __declspec(deprecated(msg))
74 # define FOLLY_DEPRECATED(msg)
79 # define FOLLY_NOINLINE __declspec(noinline)
80 #elif defined(__clang__) || defined(__GNUC__)
81 # define FOLLY_NOINLINE __attribute__((__noinline__))
83 # define FOLLY_NOINLINE
88 # define FOLLY_ALWAYS_INLINE __forceinline
89 #elif defined(__clang__) || defined(__GNUC__)
90 # define FOLLY_ALWAYS_INLINE inline __attribute__((__always_inline__))
92 # define FOLLY_ALWAYS_INLINE inline
95 // detection for 64 bit
96 #if defined(__x86_64__) || defined(_M_X64)
102 #if defined(__aarch64__)
108 #if defined (__powerpc64__)
109 # define FOLLY_PPC64 1
111 # define FOLLY_PPC64 0
114 // packing is very ugly in msvc
116 # define FOLLY_PACK_ATTR /**/
117 # define FOLLY_PACK_PUSH __pragma(pack(push, 1))
118 # define FOLLY_PACK_POP __pragma(pack(pop))
119 #elif defined(__clang__) || defined(__GNUC__)
120 # define FOLLY_PACK_ATTR __attribute__((__packed__))
121 # define FOLLY_PACK_PUSH /**/
122 # define FOLLY_PACK_POP /**/
124 # define FOLLY_PACK_ATTR /**/
125 # define FOLLY_PACK_PUSH /**/
126 # define FOLLY_PACK_POP /**/
129 // Generalize warning push/pop.
130 #if defined(_MSC_VER)
131 # define FOLLY_PUSH_WARNING __pragma(warning(push))
132 # define FOLLY_POP_WARNING __pragma(warning(pop))
133 // Disable the GCC warnings.
134 # define FOLLY_GCC_DISABLE_WARNING(warningName)
135 # define FOLLY_MSVC_DISABLE_WARNING(warningNumber) __pragma(warning(disable: warningNumber))
136 #elif defined(__clang__) || defined(__GNUC__)
137 # define FOLLY_PUSH_WARNING _Pragma("GCC diagnostic push")
138 # define FOLLY_POP_WARNING _Pragma("GCC diagnostic pop")
139 #define FOLLY_GCC_DISABLE_WARNING_INTERNAL3(warningName) #warningName
140 #define FOLLY_GCC_DISABLE_WARNING_INTERNAL2(warningName) \
141 FOLLY_GCC_DISABLE_WARNING_INTERNAL3(warningName)
142 #define FOLLY_GCC_DISABLE_WARNING(warningName) \
143 _Pragma(FOLLY_GCC_DISABLE_WARNING_INTERNAL2(GCC diagnostic ignored \
144 FOLLY_GCC_DISABLE_WARNING_INTERNAL3(-W##warningName)))
145 // Disable the MSVC warnings.
146 # define FOLLY_MSVC_DISABLE_WARNING(warningNumber)
148 # define FOLLY_PUSH_WARNING
149 # define FOLLY_POP_WARNING
150 # define FOLLY_GCC_DISABLE_WARNING(warningName)
151 # define FOLLY_MSVC_DISABLE_WARNING(warningNumber)
154 // portable version check
155 #ifndef __GNUC_PREREQ
156 # if defined __GNUC__ && defined __GNUC_MINOR__
158 # define __GNUC_PREREQ(maj, min) ((__GNUC__ << 16) + __GNUC_MINOR__ >= \
159 ((maj) << 16) + (min))
162 # define __GNUC_PREREQ(maj, min) 0
166 #if defined(__GNUC__) && !defined(__APPLE__) && !__GNUC_PREREQ(4,9)
167 // https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56019
168 // gcc 4.8.x incorrectly placed max_align_t in the root namespace
169 // Alias it into std (where it's found in 4.9 and later)
170 namespace std { typedef ::max_align_t max_align_t; }
173 // portable version check for clang
174 #ifndef __CLANG_PREREQ
175 # if defined __clang__ && defined __clang_major__ && defined __clang_minor__
177 # define __CLANG_PREREQ(maj, min) \
178 ((__clang_major__ << 16) + __clang_minor__ >= ((maj) << 16) + (min))
181 # define __CLANG_PREREQ(maj, min) 0
185 /* Platform specific TLS support
186 * gcc implements __thread
187 * msvc implements __declspec(thread)
188 * the semantics are the same
189 * (but remember __thread has different semantics when using emutls (ex. apple))
191 #if defined(_MSC_VER)
192 # define FOLLY_TLS __declspec(thread)
193 #elif defined(__GNUC__) || defined(__clang__)
194 # define FOLLY_TLS __thread
196 # error cannot define platform specific thread local storage
203 // Define to 1 if you have the `preadv' and `pwritev' functions, respectively
204 #if !defined(FOLLY_HAVE_PREADV) && !defined(FOLLY_HAVE_PWRITEV)
205 # if defined(__GLIBC_PREREQ)
206 # if __GLIBC_PREREQ(2, 10)
207 # define FOLLY_HAVE_PREADV 1
208 # define FOLLY_HAVE_PWRITEV 1
213 // It turns out that GNU libstdc++ and LLVM libc++ differ on how they implement
214 // the 'std' namespace; the latter uses inline namespaces. Wrap this decision
215 // up in a macro to make forward-declarations easier.
218 #define FOLLY_NAMESPACE_STD_BEGIN _LIBCPP_BEGIN_NAMESPACE_STD
219 #define FOLLY_NAMESPACE_STD_END _LIBCPP_END_NAMESPACE_STD
221 #define FOLLY_NAMESPACE_STD_BEGIN namespace std {
222 #define FOLLY_NAMESPACE_STD_END }
225 // If the new c++ ABI is used, __cxx11 inline namespace needs to be added to
226 // some types, e.g. std::list.
227 #if _GLIBCXX_USE_CXX11_ABI
228 # define FOLLY_GLIBCXX_NAMESPACE_CXX11_BEGIN _GLIBCXX_BEGIN_NAMESPACE_CXX11
229 # define FOLLY_GLIBCXX_NAMESPACE_CXX11_END _GLIBCXX_END_NAMESPACE_CXX11
231 # define FOLLY_GLIBCXX_NAMESPACE_CXX11_BEGIN
232 # define FOLLY_GLIBCXX_NAMESPACE_CXX11_END
235 // Provide our own std::__throw_* wrappers for platforms that don't have them
236 #if FOLLY_HAVE_BITS_FUNCTEXCEPT_H
237 #include <bits/functexcept.h>
239 #include <folly/detail/FunctionalExcept.h>
242 #if defined(__cplusplus)
243 // Unfortunately, boost::has_trivial_copy<T> is broken in libc++ due to its
244 // usage of __has_trivial_copy(), so we can't use it as a
245 // least-common-denominator for C++11 implementations that don't support
246 // std::is_trivially_copyable<T>.
248 // http://stackoverflow.com/questions/12754886/has-trivial-copy-behaves-differently-in-clang-and-gcc-whos-right
250 // As a result, use std::is_trivially_copyable() where it exists, and fall back
251 // to Boost otherwise.
252 #if FOLLY_HAVE_STD__IS_TRIVIALLY_COPYABLE
253 #include <type_traits>
254 #define FOLLY_IS_TRIVIALLY_COPYABLE(T) \
255 (std::is_trivially_copyable<T>::value)
257 #include <boost/type_traits.hpp>
258 #define FOLLY_IS_TRIVIALLY_COPYABLE(T) \
259 (boost::has_trivial_copy<T>::value && \
260 boost::has_trivial_destructor<T>::value)
262 #endif // __cplusplus
264 // MSVC specific defines
265 // mainly for posix compat
267 #include <folly/portability/SysTypes.h>
269 // sprintf semantics are not exactly identical
270 // but current usage is not a problem
271 # define snprintf _snprintf
273 // semantics here are identical
274 # define strerror_r(errno,buf,len) strerror_s(buf,len,errno)
276 // compiler specific to compiler specific
278 # define __PRETTY_FUNCTION__ __FUNCSIG__
280 // Hide a GCC specific thing that breaks MSVC if left alone.
281 # define __extension__
283 // We have compiler support for the newest of the new, but
284 // MSVC doesn't tell us that.
292 constexpr auto kIsDebug = false;
294 constexpr auto kIsDebug = true;
301 // It's MSVC, so we just have to guess ... and allow an override
302 #ifdef FOLLY_ENDIAN_BE
303 constexpr auto kIsLittleEndian = false;
305 constexpr auto kIsLittleEndian = true;
308 constexpr auto kIsLittleEndian = __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__;
310 constexpr auto kIsBigEndian = !kIsLittleEndian;
314 # if defined(__SSE4_2__)
316 # define FOLLY_SSE_MINOR 2
317 # elif defined(__SSE4_1__)
319 # define FOLLY_SSE_MINOR 1
320 # elif defined(__SSE4__)
322 # define FOLLY_SSE_MINOR 0
323 # elif defined(__SSE3__)
325 # define FOLLY_SSE_MINOR 0
326 # elif defined(__SSE2__)
328 # define FOLLY_SSE_MINOR 0
329 # elif defined(__SSE__)
331 # define FOLLY_SSE_MINOR 0
334 # define FOLLY_SSE_MINOR 0
338 #define FOLLY_SSE_PREREQ(major, minor) \
339 (FOLLY_SSE > major || FOLLY_SSE == major && FOLLY_SSE_MINOR >= minor)
341 #if FOLLY_UNUSUAL_GFLAGS_NAMESPACE
342 namespace FOLLY_GFLAGS_NAMESPACE { }
344 using namespace FOLLY_GFLAGS_NAMESPACE;
345 } // namespace gflags
348 // for TARGET_OS_IPHONE
350 #include <TargetConditionals.h>
353 // RTTI may not be enabled for this compilation unit.
354 #if defined(__GXX_RTTI) || defined(__cpp_rtti) || \
355 (defined(_MSC_VER) && defined(_CPPRTTI))
356 # define FOLLY_HAS_RTTI 1
359 #if defined(__APPLE__) || defined(_MSC_VER)
360 #define FOLLY_STATIC_CTOR_PRIORITY_MAX
362 // 101 is the highest priority allowed by the init_priority attribute.
363 // This priority is already used by JEMalloc and other memory allocators so
364 // we will take the next one.
365 #define FOLLY_STATIC_CTOR_PRIORITY_MAX __attribute__((__init_priority__(102)))