• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 //
2 // Copyright 2017 The Abseil Authors.
3 //
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
7 //
8 //      https://www.apache.org/licenses/LICENSE-2.0
9 //
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.
15 //
16 // -----------------------------------------------------------------------------
17 // File: config.h
18 // -----------------------------------------------------------------------------
19 //
20 // This header file defines a set of macros for checking the presence of
21 // important compiler and platform features. Such macros can be used to
22 // produce portable code by parameterizing compilation based on the presence or
23 // lack of a given feature.
24 //
25 // We define a "feature" as some interface we wish to program to: for example,
26 // a library function or system call. A value of `1` indicates support for
27 // that feature; any other value indicates the feature support is undefined.
28 //
29 // Example:
30 //
31 // Suppose a programmer wants to write a program that uses the 'mmap()' system
32 // call. The Abseil macro for that feature (`ABSL_HAVE_MMAP`) allows you to
33 // selectively include the `mmap.h` header and bracket code using that feature
34 // in the macro:
35 //
36 //   #include "absl/base/config.h"
37 //
38 //   #ifdef ABSL_HAVE_MMAP
39 //   #include "sys/mman.h"
40 //   #endif  //ABSL_HAVE_MMAP
41 //
42 //   ...
43 //   #ifdef ABSL_HAVE_MMAP
44 //   void *ptr = mmap(...);
45 //   ...
46 //   #endif  // ABSL_HAVE_MMAP
47 
48 #ifndef ABSL_BASE_CONFIG_H_
49 #define ABSL_BASE_CONFIG_H_
50 
51 // Included for the __GLIBC__ macro (or similar macros on other systems).
52 #include <limits.h>
53 
54 #ifdef __cplusplus
55 // Included for __GLIBCXX__, _LIBCPP_VERSION
56 #include <cstddef>
57 #endif  // __cplusplus
58 
59 // ABSL_INTERNAL_CPLUSPLUS_LANG
60 //
61 // MSVC does not set the value of __cplusplus correctly, but instead uses
62 // _MSVC_LANG as a stand-in.
63 // https://docs.microsoft.com/en-us/cpp/preprocessor/predefined-macros
64 //
65 // However, there are reports that MSVC even sets _MSVC_LANG incorrectly at
66 // times, for example:
67 // https://github.com/microsoft/vscode-cpptools/issues/1770
68 // https://reviews.llvm.org/D70996
69 //
70 // For this reason, this symbol is considered INTERNAL and code outside of
71 // Abseil must not use it.
72 #if defined(_MSVC_LANG)
73 #define ABSL_INTERNAL_CPLUSPLUS_LANG _MSVC_LANG
74 #elif defined(__cplusplus)
75 #define ABSL_INTERNAL_CPLUSPLUS_LANG __cplusplus
76 #endif
77 
78 #if defined(ABSL_INTERNAL_CPLUSPLUS_LANG) && \
79     ABSL_INTERNAL_CPLUSPLUS_LANG >= 202002L
80 // Include library feature test macros.
81 #include <version>
82 #endif
83 
84 #if defined(__APPLE__)
85 // Included for TARGET_OS_IPHONE, __IPHONE_OS_VERSION_MIN_REQUIRED,
86 // __IPHONE_8_0.
87 #include <Availability.h>
88 #include <TargetConditionals.h>
89 #endif
90 
91 #include "absl/base/options.h"
92 #include "absl/base/policy_checks.h"
93 
94 // Abseil long-term support (LTS) releases will define
95 // `ABSL_LTS_RELEASE_VERSION` to the integer representing the date string of the
96 // LTS release version, and will define `ABSL_LTS_RELEASE_PATCH_LEVEL` to the
97 // integer representing the patch-level for that release.
98 //
99 // For example, for LTS release version "20300401.2", this would give us
100 // ABSL_LTS_RELEASE_VERSION == 20300401 && ABSL_LTS_RELEASE_PATCH_LEVEL == 2
101 //
102 // These symbols will not be defined in non-LTS code.
103 //
104 // Abseil recommends that clients live-at-head. Therefore, if you are using
105 // these symbols to assert a minimum version requirement, we recommend you do it
106 // as
107 //
108 // #if defined(ABSL_LTS_RELEASE_VERSION) && ABSL_LTS_RELEASE_VERSION < 20300401
109 // #error Project foo requires Abseil LTS version >= 20300401
110 // #endif
111 //
112 // The `defined(ABSL_LTS_RELEASE_VERSION)` part of the check excludes
113 // live-at-head clients from the minimum version assertion.
114 //
115 // See https://abseil.io/about/releases for more information on Abseil release
116 // management.
117 //
118 // LTS releases can be obtained from
119 // https://github.com/abseil/abseil-cpp/releases.
120 #define ABSL_LTS_RELEASE_VERSION 20240116
121 #define ABSL_LTS_RELEASE_PATCH_LEVEL 1
122 
123 // Helper macro to convert a CPP variable to a string literal.
124 #define ABSL_INTERNAL_DO_TOKEN_STR(x) #x
125 #define ABSL_INTERNAL_TOKEN_STR(x) ABSL_INTERNAL_DO_TOKEN_STR(x)
126 
127 // -----------------------------------------------------------------------------
128 // Abseil namespace annotations
129 // -----------------------------------------------------------------------------
130 
131 // ABSL_NAMESPACE_BEGIN/ABSL_NAMESPACE_END
132 //
133 // An annotation placed at the beginning/end of each `namespace absl` scope.
134 // This is used to inject an inline namespace.
135 //
136 // The proper way to write Abseil code in the `absl` namespace is:
137 //
138 // namespace absl {
139 // ABSL_NAMESPACE_BEGIN
140 //
141 // void Foo();  // absl::Foo().
142 //
143 // ABSL_NAMESPACE_END
144 // }  // namespace absl
145 //
146 // Users of Abseil should not use these macros, because users of Abseil should
147 // not write `namespace absl {` in their own code for any reason.  (Abseil does
148 // not support forward declarations of its own types, nor does it support
149 // user-provided specialization of Abseil templates.  Code that violates these
150 // rules may be broken without warning.)
151 #if !defined(ABSL_OPTION_USE_INLINE_NAMESPACE) || \
152     !defined(ABSL_OPTION_INLINE_NAMESPACE_NAME)
153 #error options.h is misconfigured.
154 #endif
155 
156 // Check that ABSL_OPTION_INLINE_NAMESPACE_NAME is neither "head" nor ""
157 #if defined(__cplusplus) && ABSL_OPTION_USE_INLINE_NAMESPACE == 1
158 
159 #define ABSL_INTERNAL_INLINE_NAMESPACE_STR \
160   ABSL_INTERNAL_TOKEN_STR(ABSL_OPTION_INLINE_NAMESPACE_NAME)
161 
162 static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != '\0',
163               "options.h misconfigured: ABSL_OPTION_INLINE_NAMESPACE_NAME must "
164               "not be empty.");
165 static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' ||
166                   ABSL_INTERNAL_INLINE_NAMESPACE_STR[1] != 'e' ||
167                   ABSL_INTERNAL_INLINE_NAMESPACE_STR[2] != 'a' ||
168                   ABSL_INTERNAL_INLINE_NAMESPACE_STR[3] != 'd' ||
169                   ABSL_INTERNAL_INLINE_NAMESPACE_STR[4] != '\0',
170               "options.h misconfigured: ABSL_OPTION_INLINE_NAMESPACE_NAME must "
171               "be changed to a new, unique identifier name.");
172 
173 #endif
174 
175 #if ABSL_OPTION_USE_INLINE_NAMESPACE == 0
176 #define ABSL_NAMESPACE_BEGIN
177 #define ABSL_NAMESPACE_END
178 #define ABSL_INTERNAL_C_SYMBOL(x) x
179 #elif ABSL_OPTION_USE_INLINE_NAMESPACE == 1
180 #define ABSL_NAMESPACE_BEGIN \
181   inline namespace ABSL_OPTION_INLINE_NAMESPACE_NAME {
182 #define ABSL_NAMESPACE_END }
183 #define ABSL_INTERNAL_C_SYMBOL_HELPER_2(x, v) x##_##v
184 #define ABSL_INTERNAL_C_SYMBOL_HELPER_1(x, v) \
185   ABSL_INTERNAL_C_SYMBOL_HELPER_2(x, v)
186 #define ABSL_INTERNAL_C_SYMBOL(x) \
187   ABSL_INTERNAL_C_SYMBOL_HELPER_1(x, ABSL_OPTION_INLINE_NAMESPACE_NAME)
188 #else
189 #error options.h is misconfigured.
190 #endif
191 
192 // -----------------------------------------------------------------------------
193 // Compiler Feature Checks
194 // -----------------------------------------------------------------------------
195 
196 // ABSL_HAVE_BUILTIN()
197 //
198 // Checks whether the compiler supports a Clang Feature Checking Macro, and if
199 // so, checks whether it supports the provided builtin function "x" where x
200 // is one of the functions noted in
201 // https://clang.llvm.org/docs/LanguageExtensions.html
202 //
203 // Note: Use this macro to avoid an extra level of #ifdef __has_builtin check.
204 // http://releases.llvm.org/3.3/tools/clang/docs/LanguageExtensions.html
205 #ifdef __has_builtin
206 #define ABSL_HAVE_BUILTIN(x) __has_builtin(x)
207 #else
208 #define ABSL_HAVE_BUILTIN(x) 0
209 #endif
210 
211 #ifdef __has_feature
212 #define ABSL_HAVE_FEATURE(f) __has_feature(f)
213 #else
214 #define ABSL_HAVE_FEATURE(f) 0
215 #endif
216 
217 // Portable check for GCC minimum version:
218 // https://gcc.gnu.org/onlinedocs/cpp/Common-Predefined-Macros.html
219 #if defined(__GNUC__) && defined(__GNUC_MINOR__)
220 #define ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(x, y) \
221   (__GNUC__ > (x) || __GNUC__ == (x) && __GNUC_MINOR__ >= (y))
222 #else
223 #define ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(x, y) 0
224 #endif
225 
226 #if defined(__clang__) && defined(__clang_major__) && defined(__clang_minor__)
227 #define ABSL_INTERNAL_HAVE_MIN_CLANG_VERSION(x, y) \
228   (__clang_major__ > (x) || __clang_major__ == (x) && __clang_minor__ >= (y))
229 #else
230 #define ABSL_INTERNAL_HAVE_MIN_CLANG_VERSION(x, y) 0
231 #endif
232 
233 // ABSL_HAVE_TLS is defined to 1 when __thread should be supported.
234 // We assume __thread is supported on Linux or Asylo when compiled with Clang or
235 // compiled against libstdc++ with _GLIBCXX_HAVE_TLS defined.
236 #ifdef ABSL_HAVE_TLS
237 #error ABSL_HAVE_TLS cannot be directly set
238 #elif (defined(__linux__) || defined(__ASYLO__)) && \
239     (defined(__clang__) || defined(_GLIBCXX_HAVE_TLS))
240 #define ABSL_HAVE_TLS 1
241 #endif
242 
243 // ABSL_HAVE_STD_IS_TRIVIALLY_DESTRUCTIBLE
244 //
245 // Checks whether `std::is_trivially_destructible<T>` is supported.
246 #ifdef ABSL_HAVE_STD_IS_TRIVIALLY_DESTRUCTIBLE
247 #error ABSL_HAVE_STD_IS_TRIVIALLY_DESTRUCTIBLE cannot be directly set
248 #define ABSL_HAVE_STD_IS_TRIVIALLY_DESTRUCTIBLE 1
249 #endif
250 
251 // ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE
252 //
253 // Checks whether `std::is_trivially_default_constructible<T>` and
254 // `std::is_trivially_copy_constructible<T>` are supported.
255 #ifdef ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE
256 #error ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE cannot be directly set
257 #else
258 #define ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE 1
259 #endif
260 
261 // ABSL_HAVE_STD_IS_TRIVIALLY_ASSIGNABLE
262 //
263 // Checks whether `std::is_trivially_copy_assignable<T>` is supported.
264 #ifdef ABSL_HAVE_STD_IS_TRIVIALLY_ASSIGNABLE
265 #error ABSL_HAVE_STD_IS_TRIVIALLY_ASSIGNABLE cannot be directly set
266 #else
267 #define ABSL_HAVE_STD_IS_TRIVIALLY_ASSIGNABLE 1
268 #endif
269 
270 // ABSL_HAVE_STD_IS_TRIVIALLY_COPYABLE
271 //
272 // Checks whether `std::is_trivially_copyable<T>` is supported.
273 #ifdef ABSL_HAVE_STD_IS_TRIVIALLY_COPYABLE
274 #error ABSL_HAVE_STD_IS_TRIVIALLY_COPYABLE cannot be directly set
275 #define ABSL_HAVE_STD_IS_TRIVIALLY_COPYABLE 1
276 #endif
277 
278 // ABSL_HAVE_THREAD_LOCAL
279 //
280 // Checks whether C++11's `thread_local` storage duration specifier is
281 // supported.
282 #ifdef ABSL_HAVE_THREAD_LOCAL
283 #error ABSL_HAVE_THREAD_LOCAL cannot be directly set
284 #elif defined(__APPLE__)
285 // Notes:
286 // * Xcode's clang did not support `thread_local` until version 8, and
287 //   even then not for all iOS < 9.0.
288 // * Xcode 9.3 started disallowing `thread_local` for 32-bit iOS simulator
289 //   targeting iOS 9.x.
290 // * Xcode 10 moves the deployment target check for iOS < 9.0 to link time
291 //   making ABSL_HAVE_FEATURE unreliable there.
292 //
293 #if ABSL_HAVE_FEATURE(cxx_thread_local) && \
294     !(TARGET_OS_IPHONE && __IPHONE_OS_VERSION_MIN_REQUIRED < __IPHONE_9_0)
295 #define ABSL_HAVE_THREAD_LOCAL 1
296 #endif
297 #else  // !defined(__APPLE__)
298 #define ABSL_HAVE_THREAD_LOCAL 1
299 #endif
300 
301 // There are platforms for which TLS should not be used even though the compiler
302 // makes it seem like it's supported (Android NDK < r12b for example).
303 // This is primarily because of linker problems and toolchain misconfiguration:
304 // Abseil does not intend to support this indefinitely. Currently, the newest
305 // toolchain that we intend to support that requires this behavior is the
306 // r11 NDK - allowing for a 5 year support window on that means this option
307 // is likely to be removed around June of 2021.
308 // TLS isn't supported until NDK r12b per
309 // https://developer.android.com/ndk/downloads/revision_history.html
310 // Since NDK r16, `__NDK_MAJOR__` and `__NDK_MINOR__` are defined in
311 // <android/ndk-version.h>. For NDK < r16, users should define these macros,
312 // e.g. `-D__NDK_MAJOR__=11 -D__NKD_MINOR__=0` for NDK r11.
313 #if defined(__ANDROID__) && defined(__clang__)
314 #if __has_include(<android/ndk-version.h>)
315 #include <android/ndk-version.h>
316 #endif  // __has_include(<android/ndk-version.h>)
317 #if defined(__ANDROID__) && defined(__clang__) && defined(__NDK_MAJOR__) && \
318     defined(__NDK_MINOR__) &&                                               \
319     ((__NDK_MAJOR__ < 12) || ((__NDK_MAJOR__ == 12) && (__NDK_MINOR__ < 1)))
320 #undef ABSL_HAVE_TLS
321 #undef ABSL_HAVE_THREAD_LOCAL
322 #endif
323 #endif  // defined(__ANDROID__) && defined(__clang__)
324 
325 // ABSL_HAVE_INTRINSIC_INT128
326 //
327 // Checks whether the __int128 compiler extension for a 128-bit integral type is
328 // supported.
329 //
330 // Note: __SIZEOF_INT128__ is defined by Clang and GCC when __int128 is
331 // supported, but we avoid using it in certain cases:
332 // * On Clang:
333 //   * Building using Clang for Windows, where the Clang runtime library has
334 //     128-bit support only on LP64 architectures, but Windows is LLP64.
335 // * On Nvidia's nvcc:
336 //   * nvcc also defines __GNUC__ and __SIZEOF_INT128__, but not all versions
337 //     actually support __int128.
338 #ifdef ABSL_HAVE_INTRINSIC_INT128
339 #error ABSL_HAVE_INTRINSIC_INT128 cannot be directly set
340 #elif defined(__SIZEOF_INT128__)
341 #if (defined(__clang__) && !defined(_WIN32)) ||           \
342     (defined(__CUDACC__) && __CUDACC_VER_MAJOR__ >= 9) || \
343     (defined(__GNUC__) && !defined(__clang__) && !defined(__CUDACC__))
344 #define ABSL_HAVE_INTRINSIC_INT128 1
345 #elif defined(__CUDACC__)
346 // __CUDACC_VER__ is a full version number before CUDA 9, and is defined to a
347 // string explaining that it has been removed starting with CUDA 9. We use
348 // nested #ifs because there is no short-circuiting in the preprocessor.
349 // NOTE: `__CUDACC__` could be undefined while `__CUDACC_VER__` is defined.
350 #if __CUDACC_VER__ >= 70000
351 #define ABSL_HAVE_INTRINSIC_INT128 1
352 #endif  // __CUDACC_VER__ >= 70000
353 #endif  // defined(__CUDACC__)
354 #endif  // ABSL_HAVE_INTRINSIC_INT128
355 
356 // ABSL_HAVE_EXCEPTIONS
357 //
358 // Checks whether the compiler both supports and enables exceptions. Many
359 // compilers support a "no exceptions" mode that disables exceptions.
360 //
361 // Generally, when ABSL_HAVE_EXCEPTIONS is not defined:
362 //
363 // * Code using `throw` and `try` may not compile.
364 // * The `noexcept` specifier will still compile and behave as normal.
365 // * The `noexcept` operator may still return `false`.
366 //
367 // For further details, consult the compiler's documentation.
368 #ifdef ABSL_HAVE_EXCEPTIONS
369 #error ABSL_HAVE_EXCEPTIONS cannot be directly set.
370 #elif ABSL_INTERNAL_HAVE_MIN_CLANG_VERSION(3, 6)
371 // Clang >= 3.6
372 #if ABSL_HAVE_FEATURE(cxx_exceptions)
373 #define ABSL_HAVE_EXCEPTIONS 1
374 #endif  // ABSL_HAVE_FEATURE(cxx_exceptions)
375 #elif defined(__clang__)
376 // Clang < 3.6
377 // http://releases.llvm.org/3.6.0/tools/clang/docs/ReleaseNotes.html#the-exceptions-macro
378 #if defined(__EXCEPTIONS) && ABSL_HAVE_FEATURE(cxx_exceptions)
379 #define ABSL_HAVE_EXCEPTIONS 1
380 #endif  // defined(__EXCEPTIONS) && ABSL_HAVE_FEATURE(cxx_exceptions)
381 // Handle remaining special cases and default to exceptions being supported.
382 #elif !(defined(__GNUC__) && (__GNUC__ < 5) && !defined(__EXCEPTIONS)) && \
383     !(ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(5, 0) &&                        \
384       !defined(__cpp_exceptions)) &&                                      \
385     !(defined(_MSC_VER) && !defined(_CPPUNWIND))
386 #define ABSL_HAVE_EXCEPTIONS 1
387 #endif
388 
389 // -----------------------------------------------------------------------------
390 // Platform Feature Checks
391 // -----------------------------------------------------------------------------
392 
393 // Currently supported operating systems and associated preprocessor
394 // symbols:
395 //
396 //   Linux and Linux-derived           __linux__
397 //   Android                           __ANDROID__ (implies __linux__)
398 //   Linux (non-Android)               __linux__ && !__ANDROID__
399 //   Darwin (macOS and iOS)            __APPLE__
400 //   Akaros (http://akaros.org)        __ros__
401 //   Windows                           _WIN32
402 //   NaCL                              __native_client__
403 //   AsmJS                             __asmjs__
404 //   WebAssembly (Emscripten)          __EMSCRIPTEN__
405 //   Fuchsia                           __Fuchsia__
406 //
407 // Note that since Android defines both __ANDROID__ and __linux__, one
408 // may probe for either Linux or Android by simply testing for __linux__.
409 
410 // ABSL_HAVE_MMAP
411 //
412 // Checks whether the platform has an mmap(2) implementation as defined in
413 // POSIX.1-2001.
414 #ifdef ABSL_HAVE_MMAP
415 #error ABSL_HAVE_MMAP cannot be directly set
416 #elif defined(__linux__) || defined(__APPLE__) || defined(__FreeBSD__) ||    \
417     defined(_AIX) || defined(__ros__) || defined(__native_client__) ||       \
418     defined(__asmjs__) || defined(__EMSCRIPTEN__) || defined(__Fuchsia__) || \
419     defined(__sun) || defined(__ASYLO__) || defined(__myriad2__) ||          \
420     defined(__HAIKU__) || defined(__OpenBSD__) || defined(__NetBSD__) ||     \
421     defined(__QNX__) || defined(__VXWORKS__) || defined(__hexagon__)
422 #define ABSL_HAVE_MMAP 1
423 #endif
424 
425 // ABSL_HAVE_PTHREAD_GETSCHEDPARAM
426 //
427 // Checks whether the platform implements the pthread_(get|set)schedparam(3)
428 // functions as defined in POSIX.1-2001.
429 #ifdef ABSL_HAVE_PTHREAD_GETSCHEDPARAM
430 #error ABSL_HAVE_PTHREAD_GETSCHEDPARAM cannot be directly set
431 #elif defined(__linux__) || defined(__APPLE__) || defined(__FreeBSD__) || \
432     defined(_AIX) || defined(__ros__) || defined(__OpenBSD__) ||          \
433     defined(__NetBSD__) || defined(__VXWORKS__)
434 #define ABSL_HAVE_PTHREAD_GETSCHEDPARAM 1
435 #endif
436 
437 // ABSL_HAVE_SCHED_GETCPU
438 //
439 // Checks whether sched_getcpu is available.
440 #ifdef ABSL_HAVE_SCHED_GETCPU
441 #error ABSL_HAVE_SCHED_GETCPU cannot be directly set
442 #elif defined(__linux__)
443 #define ABSL_HAVE_SCHED_GETCPU 1
444 #endif
445 
446 // ABSL_HAVE_SCHED_YIELD
447 //
448 // Checks whether the platform implements sched_yield(2) as defined in
449 // POSIX.1-2001.
450 #ifdef ABSL_HAVE_SCHED_YIELD
451 #error ABSL_HAVE_SCHED_YIELD cannot be directly set
452 #elif defined(__linux__) || defined(__ros__) || defined(__native_client__) || \
453     defined(__VXWORKS__)
454 #define ABSL_HAVE_SCHED_YIELD 1
455 #endif
456 
457 // ABSL_HAVE_SEMAPHORE_H
458 //
459 // Checks whether the platform supports the <semaphore.h> header and sem_init(3)
460 // family of functions as standardized in POSIX.1-2001.
461 //
462 // Note: While Apple provides <semaphore.h> for both iOS and macOS, it is
463 // explicitly deprecated and will cause build failures if enabled for those
464 // platforms.  We side-step the issue by not defining it here for Apple
465 // platforms.
466 #ifdef ABSL_HAVE_SEMAPHORE_H
467 #error ABSL_HAVE_SEMAPHORE_H cannot be directly set
468 #elif defined(__linux__) || defined(__ros__) || defined(__VXWORKS__)
469 #define ABSL_HAVE_SEMAPHORE_H 1
470 #endif
471 
472 // ABSL_HAVE_ALARM
473 //
474 // Checks whether the platform supports the <signal.h> header and alarm(2)
475 // function as standardized in POSIX.1-2001.
476 #ifdef ABSL_HAVE_ALARM
477 #error ABSL_HAVE_ALARM cannot be directly set
478 #elif defined(__GOOGLE_GRTE_VERSION__)
479 // feature tests for Google's GRTE
480 #define ABSL_HAVE_ALARM 1
481 #elif defined(__GLIBC__)
482 // feature test for glibc
483 #define ABSL_HAVE_ALARM 1
484 #elif defined(_MSC_VER)
485 // feature tests for Microsoft's library
486 #elif defined(__MINGW32__)
487 // mingw32 doesn't provide alarm(2):
488 // https://osdn.net/projects/mingw/scm/git/mingw-org-wsl/blobs/5.2-trunk/mingwrt/include/unistd.h
489 // mingw-w64 provides a no-op implementation:
490 // https://sourceforge.net/p/mingw-w64/mingw-w64/ci/master/tree/mingw-w64-crt/misc/alarm.c
491 #elif defined(__EMSCRIPTEN__)
492 // emscripten doesn't support signals
493 #elif defined(__wasi__)
494 // WASI doesn't support signals
495 #elif defined(__Fuchsia__)
496 // Signals don't exist on fuchsia.
497 #elif defined(__native_client__)
498 // Signals don't exist on hexagon/QuRT
499 #elif defined(__hexagon__)
500 #else
501 // other standard libraries
502 #define ABSL_HAVE_ALARM 1
503 #endif
504 
505 // ABSL_IS_LITTLE_ENDIAN
506 // ABSL_IS_BIG_ENDIAN
507 //
508 // Checks the endianness of the platform.
509 //
510 // Notes: uses the built in endian macros provided by GCC (since 4.6) and
511 // Clang (since 3.2); see
512 // https://gcc.gnu.org/onlinedocs/cpp/Common-Predefined-Macros.html.
513 // Otherwise, if _WIN32, assume little endian. Otherwise, bail with an error.
514 #if defined(ABSL_IS_BIG_ENDIAN)
515 #error "ABSL_IS_BIG_ENDIAN cannot be directly set."
516 #endif
517 #if defined(ABSL_IS_LITTLE_ENDIAN)
518 #error "ABSL_IS_LITTLE_ENDIAN cannot be directly set."
519 #endif
520 
521 #if (defined(__BYTE_ORDER__) && defined(__ORDER_LITTLE_ENDIAN__) && \
522      __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__)
523 #define ABSL_IS_LITTLE_ENDIAN 1
524 #elif defined(__BYTE_ORDER__) && defined(__ORDER_BIG_ENDIAN__) && \
525     __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
526 #define ABSL_IS_BIG_ENDIAN 1
527 #elif defined(_WIN32)
528 #define ABSL_IS_LITTLE_ENDIAN 1
529 #else
530 #error "absl endian detection needs to be set up for your compiler"
531 #endif
532 
533 // macOS < 10.13 and iOS < 12 don't support <any>, <optional>, or <variant>
534 // because the libc++ shared library shipped on the system doesn't have the
535 // requisite exported symbols.  See
536 // https://github.com/abseil/abseil-cpp/issues/207 and
537 // https://developer.apple.com/documentation/xcode_release_notes/xcode_10_release_notes
538 //
539 // libc++ spells out the availability requirements in the file
540 // llvm-project/libcxx/include/__config via the #define
541 // _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS. The set of versions has been
542 // modified a few times, via
543 // https://github.com/llvm/llvm-project/commit/7fb40e1569dd66292b647f4501b85517e9247953
544 // and
545 // https://github.com/llvm/llvm-project/commit/0bc451e7e137c4ccadcd3377250874f641ca514a
546 // The second has the actually correct versions, thus, is what we copy here.
547 #if defined(__APPLE__) &&                                         \
548     ((defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) &&   \
549       __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101300) ||  \
550      (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) &&  \
551       __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 120000) || \
552      (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) &&   \
553       __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 50000) ||   \
554      (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) &&      \
555       __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 120000))
556 #define ABSL_INTERNAL_APPLE_CXX17_TYPES_UNAVAILABLE 1
557 #else
558 #define ABSL_INTERNAL_APPLE_CXX17_TYPES_UNAVAILABLE 0
559 #endif
560 
561 // ABSL_HAVE_STD_ANY
562 //
563 // Checks whether C++17 std::any is available.
564 #ifdef ABSL_HAVE_STD_ANY
565 #error "ABSL_HAVE_STD_ANY cannot be directly set."
566 #elif defined(__cpp_lib_any) && __cpp_lib_any >= 201606L
567 #define ABSL_HAVE_STD_ANY 1
568 #elif defined(ABSL_INTERNAL_CPLUSPLUS_LANG) && \
569     ABSL_INTERNAL_CPLUSPLUS_LANG >= 201703L && \
570     !ABSL_INTERNAL_APPLE_CXX17_TYPES_UNAVAILABLE
571 #define ABSL_HAVE_STD_ANY 1
572 #endif
573 
574 // ABSL_HAVE_STD_OPTIONAL
575 //
576 // Checks whether C++17 std::optional is available.
577 #ifdef ABSL_HAVE_STD_OPTIONAL
578 #error "ABSL_HAVE_STD_OPTIONAL cannot be directly set."
579 #elif defined(__cpp_lib_optional) && __cpp_lib_optional >= 202106L
580 #define ABSL_HAVE_STD_OPTIONAL 1
581 #elif defined(ABSL_INTERNAL_CPLUSPLUS_LANG) && \
582     ABSL_INTERNAL_CPLUSPLUS_LANG >= 201703L && \
583     !ABSL_INTERNAL_APPLE_CXX17_TYPES_UNAVAILABLE
584 #define ABSL_HAVE_STD_OPTIONAL 1
585 #endif
586 
587 // ABSL_HAVE_STD_VARIANT
588 //
589 // Checks whether C++17 std::variant is available.
590 #ifdef ABSL_HAVE_STD_VARIANT
591 #error "ABSL_HAVE_STD_VARIANT cannot be directly set."
592 #elif defined(__cpp_lib_variant) && __cpp_lib_variant >= 201606L
593 #define ABSL_HAVE_STD_VARIANT 1
594 #elif defined(ABSL_INTERNAL_CPLUSPLUS_LANG) && \
595     ABSL_INTERNAL_CPLUSPLUS_LANG >= 201703L && \
596     !ABSL_INTERNAL_APPLE_CXX17_TYPES_UNAVAILABLE
597 #define ABSL_HAVE_STD_VARIANT 1
598 #endif
599 
600 // ABSL_HAVE_STD_STRING_VIEW
601 //
602 // Checks whether C++17 std::string_view is available.
603 #ifdef ABSL_HAVE_STD_STRING_VIEW
604 #error "ABSL_HAVE_STD_STRING_VIEW cannot be directly set."
605 #elif defined(__cpp_lib_string_view) && __cpp_lib_string_view >= 201606L
606 #define ABSL_HAVE_STD_STRING_VIEW 1
607 #elif defined(ABSL_INTERNAL_CPLUSPLUS_LANG) && \
608     ABSL_INTERNAL_CPLUSPLUS_LANG >= 201703L
609 #define ABSL_HAVE_STD_STRING_VIEW 1
610 #endif
611 
612 // ABSL_HAVE_STD_ORDERING
613 //
614 // Checks whether C++20 std::{partial,weak,strong}_ordering are available.
615 //
616 // __cpp_lib_three_way_comparison is missing on libc++
617 // (https://github.com/llvm/llvm-project/issues/73953) so treat it as defined
618 // when building in C++20 mode.
619 #ifdef ABSL_HAVE_STD_ORDERING
620 #error "ABSL_HAVE_STD_ORDERING cannot be directly set."
621 #elif (defined(__cpp_lib_three_way_comparison) &&    \
622        __cpp_lib_three_way_comparison >= 201907L) || \
623     (defined(ABSL_INTERNAL_CPLUSPLUS_LANG) &&        \
624      ABSL_INTERNAL_CPLUSPLUS_LANG >= 202002L)
625 #define ABSL_HAVE_STD_ORDERING 1
626 #endif
627 
628 // ABSL_USES_STD_ANY
629 //
630 // Indicates whether absl::any is an alias for std::any.
631 #if !defined(ABSL_OPTION_USE_STD_ANY)
632 #error options.h is misconfigured.
633 #elif ABSL_OPTION_USE_STD_ANY == 0 || \
634     (ABSL_OPTION_USE_STD_ANY == 2 && !defined(ABSL_HAVE_STD_ANY))
635 #undef ABSL_USES_STD_ANY
636 #elif ABSL_OPTION_USE_STD_ANY == 1 || \
637     (ABSL_OPTION_USE_STD_ANY == 2 && defined(ABSL_HAVE_STD_ANY))
638 #define ABSL_USES_STD_ANY 1
639 #else
640 #error options.h is misconfigured.
641 #endif
642 
643 // ABSL_USES_STD_OPTIONAL
644 //
645 // Indicates whether absl::optional is an alias for std::optional.
646 #if !defined(ABSL_OPTION_USE_STD_OPTIONAL)
647 #error options.h is misconfigured.
648 #elif ABSL_OPTION_USE_STD_OPTIONAL == 0 || \
649     (ABSL_OPTION_USE_STD_OPTIONAL == 2 && !defined(ABSL_HAVE_STD_OPTIONAL))
650 #undef ABSL_USES_STD_OPTIONAL
651 #elif ABSL_OPTION_USE_STD_OPTIONAL == 1 || \
652     (ABSL_OPTION_USE_STD_OPTIONAL == 2 && defined(ABSL_HAVE_STD_OPTIONAL))
653 #define ABSL_USES_STD_OPTIONAL 1
654 #else
655 #error options.h is misconfigured.
656 #endif
657 
658 // ABSL_USES_STD_VARIANT
659 //
660 // Indicates whether absl::variant is an alias for std::variant.
661 #if !defined(ABSL_OPTION_USE_STD_VARIANT)
662 #error options.h is misconfigured.
663 #elif ABSL_OPTION_USE_STD_VARIANT == 0 || \
664     (ABSL_OPTION_USE_STD_VARIANT == 2 && !defined(ABSL_HAVE_STD_VARIANT))
665 #undef ABSL_USES_STD_VARIANT
666 #elif ABSL_OPTION_USE_STD_VARIANT == 1 || \
667     (ABSL_OPTION_USE_STD_VARIANT == 2 && defined(ABSL_HAVE_STD_VARIANT))
668 #define ABSL_USES_STD_VARIANT 1
669 #else
670 #error options.h is misconfigured.
671 #endif
672 
673 // ABSL_USES_STD_STRING_VIEW
674 //
675 // Indicates whether absl::string_view is an alias for std::string_view.
676 #if !defined(ABSL_OPTION_USE_STD_STRING_VIEW)
677 #error options.h is misconfigured.
678 #elif ABSL_OPTION_USE_STD_STRING_VIEW == 0 || \
679     (ABSL_OPTION_USE_STD_STRING_VIEW == 2 &&  \
680      !defined(ABSL_HAVE_STD_STRING_VIEW))
681 #undef ABSL_USES_STD_STRING_VIEW
682 #elif ABSL_OPTION_USE_STD_STRING_VIEW == 1 || \
683     (ABSL_OPTION_USE_STD_STRING_VIEW == 2 &&  \
684      defined(ABSL_HAVE_STD_STRING_VIEW))
685 #define ABSL_USES_STD_STRING_VIEW 1
686 #else
687 #error options.h is misconfigured.
688 #endif
689 
690 // ABSL_USES_STD_ORDERING
691 //
692 // Indicates whether absl::{partial,weak,strong}_ordering are aliases for the
693 // std:: ordering types.
694 #if !defined(ABSL_OPTION_USE_STD_ORDERING)
695 #error options.h is misconfigured.
696 #elif ABSL_OPTION_USE_STD_ORDERING == 0 || \
697     (ABSL_OPTION_USE_STD_ORDERING == 2 && !defined(ABSL_HAVE_STD_ORDERING))
698 #undef ABSL_USES_STD_ORDERING
699 #elif ABSL_OPTION_USE_STD_ORDERING == 1 || \
700     (ABSL_OPTION_USE_STD_ORDERING == 2 && defined(ABSL_HAVE_STD_ORDERING))
701 #define ABSL_USES_STD_ORDERING 1
702 #else
703 #error options.h is misconfigured.
704 #endif
705 
706 // In debug mode, MSVC 2017's std::variant throws a EXCEPTION_ACCESS_VIOLATION
707 // SEH exception from emplace for variant<SomeStruct> when constructing the
708 // struct can throw. This defeats some of variant_test and
709 // variant_exception_safety_test.
710 #if defined(_MSC_VER) && _MSC_VER >= 1700 && defined(_DEBUG)
711 #define ABSL_INTERNAL_MSVC_2017_DBG_MODE
712 #endif
713 
714 // ABSL_INTERNAL_MANGLED_NS
715 // ABSL_INTERNAL_MANGLED_BACKREFERENCE
716 //
717 // Internal macros for building up mangled names in our internal fork of CCTZ.
718 // This implementation detail is only needed and provided for the MSVC build.
719 //
720 // These macros both expand to string literals.  ABSL_INTERNAL_MANGLED_NS is
721 // the mangled spelling of the `absl` namespace, and
722 // ABSL_INTERNAL_MANGLED_BACKREFERENCE is a back-reference integer representing
723 // the proper count to skip past the CCTZ fork namespace names.  (This number
724 // is one larger when there is an inline namespace name to skip.)
725 #if defined(_MSC_VER)
726 #if ABSL_OPTION_USE_INLINE_NAMESPACE == 0
727 #define ABSL_INTERNAL_MANGLED_NS "absl"
728 #define ABSL_INTERNAL_MANGLED_BACKREFERENCE "5"
729 #else
730 #define ABSL_INTERNAL_MANGLED_NS \
731   ABSL_INTERNAL_TOKEN_STR(ABSL_OPTION_INLINE_NAMESPACE_NAME) "@absl"
732 #define ABSL_INTERNAL_MANGLED_BACKREFERENCE "6"
733 #endif
734 #endif
735 
736 // ABSL_DLL
737 //
738 // When building Abseil as a DLL, this macro expands to `__declspec(dllexport)`
739 // so we can annotate symbols appropriately as being exported. When used in
740 // headers consuming a DLL, this macro expands to `__declspec(dllimport)` so
741 // that consumers know the symbol is defined inside the DLL. In all other cases,
742 // the macro expands to nothing.
743 #if defined(_MSC_VER)
744 #if defined(ABSL_BUILD_DLL)
745 #define ABSL_DLL __declspec(dllexport)
746 #elif defined(ABSL_CONSUME_DLL)
747 #define ABSL_DLL __declspec(dllimport)
748 #else
749 #define ABSL_DLL
750 #endif
751 #else
752 #define ABSL_DLL
753 #endif  // defined(_MSC_VER)
754 
755 #if defined(_MSC_VER)
756 #if defined(ABSL_BUILD_TEST_DLL)
757 #define ABSL_TEST_DLL __declspec(dllexport)
758 #elif defined(ABSL_CONSUME_TEST_DLL)
759 #define ABSL_TEST_DLL __declspec(dllimport)
760 #else
761 #define ABSL_TEST_DLL
762 #endif
763 #else
764 #define ABSL_TEST_DLL
765 #endif  // defined(_MSC_VER)
766 
767 // ABSL_HAVE_MEMORY_SANITIZER
768 //
769 // MemorySanitizer (MSan) is a detector of uninitialized reads. It consists of
770 // a compiler instrumentation module and a run-time library.
771 #ifdef ABSL_HAVE_MEMORY_SANITIZER
772 #error "ABSL_HAVE_MEMORY_SANITIZER cannot be directly set."
773 #elif !defined(__native_client__) && ABSL_HAVE_FEATURE(memory_sanitizer)
774 #define ABSL_HAVE_MEMORY_SANITIZER 1
775 #endif
776 
777 // ABSL_HAVE_THREAD_SANITIZER
778 //
779 // ThreadSanitizer (TSan) is a fast data race detector.
780 #ifdef ABSL_HAVE_THREAD_SANITIZER
781 #error "ABSL_HAVE_THREAD_SANITIZER cannot be directly set."
782 #elif defined(__SANITIZE_THREAD__)
783 #define ABSL_HAVE_THREAD_SANITIZER 1
784 #elif ABSL_HAVE_FEATURE(thread_sanitizer)
785 #define ABSL_HAVE_THREAD_SANITIZER 1
786 #endif
787 
788 // ABSL_HAVE_ADDRESS_SANITIZER
789 //
790 // AddressSanitizer (ASan) is a fast memory error detector.
791 #ifdef ABSL_HAVE_ADDRESS_SANITIZER
792 #error "ABSL_HAVE_ADDRESS_SANITIZER cannot be directly set."
793 #elif defined(__SANITIZE_ADDRESS__)
794 #define ABSL_HAVE_ADDRESS_SANITIZER 1
795 #elif ABSL_HAVE_FEATURE(address_sanitizer)
796 #define ABSL_HAVE_ADDRESS_SANITIZER 1
797 #endif
798 
799 // ABSL_HAVE_HWADDRESS_SANITIZER
800 //
801 // Hardware-Assisted AddressSanitizer (or HWASAN) is even faster than asan
802 // memory error detector which can use CPU features like ARM TBI, Intel LAM or
803 // AMD UAI.
804 #ifdef ABSL_HAVE_HWADDRESS_SANITIZER
805 #error "ABSL_HAVE_HWADDRESS_SANITIZER cannot be directly set."
806 #elif defined(__SANITIZE_HWADDRESS__)
807 #define ABSL_HAVE_HWADDRESS_SANITIZER 1
808 #elif ABSL_HAVE_FEATURE(hwaddress_sanitizer)
809 #define ABSL_HAVE_HWADDRESS_SANITIZER 1
810 #endif
811 
812 // ABSL_HAVE_DATAFLOW_SANITIZER
813 //
814 // Dataflow Sanitizer (or DFSAN) is a generalised dynamic data flow analysis.
815 #ifdef ABSL_HAVE_DATAFLOW_SANITIZER
816 #error "ABSL_HAVE_DATAFLOW_SANITIZER cannot be directly set."
817 #elif defined(DATAFLOW_SANITIZER)
818 // GCC provides no method for detecting the presence of the standalone
819 // DataFlowSanitizer (-fsanitize=dataflow), so GCC users of -fsanitize=dataflow
820 // should also use -DDATAFLOW_SANITIZER.
821 #define ABSL_HAVE_DATAFLOW_SANITIZER 1
822 #elif ABSL_HAVE_FEATURE(dataflow_sanitizer)
823 #define ABSL_HAVE_DATAFLOW_SANITIZER 1
824 #endif
825 
826 // ABSL_HAVE_LEAK_SANITIZER
827 //
828 // LeakSanitizer (or lsan) is a detector of memory leaks.
829 // https://clang.llvm.org/docs/LeakSanitizer.html
830 // https://github.com/google/sanitizers/wiki/AddressSanitizerLeakSanitizer
831 //
832 // The macro ABSL_HAVE_LEAK_SANITIZER can be used to detect at compile-time
833 // whether the LeakSanitizer is potentially available. However, just because the
834 // LeakSanitizer is available does not mean it is active. Use the
835 // always-available run-time interface in //absl/debugging/leak_check.h for
836 // interacting with LeakSanitizer.
837 #ifdef ABSL_HAVE_LEAK_SANITIZER
838 #error "ABSL_HAVE_LEAK_SANITIZER cannot be directly set."
839 #elif defined(LEAK_SANITIZER)
840 // GCC provides no method for detecting the presence of the standalone
841 // LeakSanitizer (-fsanitize=leak), so GCC users of -fsanitize=leak should also
842 // use -DLEAK_SANITIZER.
843 #define ABSL_HAVE_LEAK_SANITIZER 1
844 // Clang standalone LeakSanitizer (-fsanitize=leak)
845 #elif ABSL_HAVE_FEATURE(leak_sanitizer)
846 #define ABSL_HAVE_LEAK_SANITIZER 1
847 #elif defined(ABSL_HAVE_ADDRESS_SANITIZER)
848 // GCC or Clang using the LeakSanitizer integrated into AddressSanitizer.
849 #define ABSL_HAVE_LEAK_SANITIZER 1
850 #endif
851 
852 // ABSL_HAVE_CLASS_TEMPLATE_ARGUMENT_DEDUCTION
853 //
854 // Class template argument deduction is a language feature added in C++17.
855 #ifdef ABSL_HAVE_CLASS_TEMPLATE_ARGUMENT_DEDUCTION
856 #error "ABSL_HAVE_CLASS_TEMPLATE_ARGUMENT_DEDUCTION cannot be directly set."
857 #elif defined(__cpp_deduction_guides)
858 #define ABSL_HAVE_CLASS_TEMPLATE_ARGUMENT_DEDUCTION 1
859 #endif
860 
861 // ABSL_INTERNAL_NEED_REDUNDANT_CONSTEXPR_DECL
862 //
863 // Prior to C++17, static constexpr variables defined in classes required a
864 // separate definition outside of the class body, for example:
865 //
866 // class Foo {
867 //   static constexpr int kBar = 0;
868 // };
869 // constexpr int Foo::kBar;
870 //
871 // In C++17, these variables defined in classes are considered inline variables,
872 // and the extra declaration is redundant. Since some compilers warn on the
873 // extra declarations, ABSL_INTERNAL_NEED_REDUNDANT_CONSTEXPR_DECL can be used
874 // conditionally ignore them:
875 //
876 // #ifdef ABSL_INTERNAL_NEED_REDUNDANT_CONSTEXPR_DECL
877 // constexpr int Foo::kBar;
878 // #endif
879 #if defined(ABSL_INTERNAL_CPLUSPLUS_LANG) && \
880     ABSL_INTERNAL_CPLUSPLUS_LANG < 201703L
881 #define ABSL_INTERNAL_NEED_REDUNDANT_CONSTEXPR_DECL 1
882 #endif
883 
884 // `ABSL_INTERNAL_HAS_RTTI` determines whether abseil is being compiled with
885 // RTTI support.
886 #ifdef ABSL_INTERNAL_HAS_RTTI
887 #error ABSL_INTERNAL_HAS_RTTI cannot be directly set
888 #elif ABSL_HAVE_FEATURE(cxx_rtti)
889 #define ABSL_INTERNAL_HAS_RTTI 1
890 #elif defined(__GNUC__) && defined(__GXX_RTTI)
891 #define ABSL_INTERNAL_HAS_RTTI 1
892 #elif defined(_MSC_VER) && defined(_CPPRTTI)
893 #define ABSL_INTERNAL_HAS_RTTI 1
894 #elif !defined(__GNUC__) && !defined(_MSC_VER)
895 // Unknown compiler, default to RTTI
896 #define ABSL_INTERNAL_HAS_RTTI 1
897 #endif
898 
899 // `ABSL_INTERNAL_HAS_CXA_DEMANGLE` determines whether `abi::__cxa_demangle` is
900 // available.
901 #ifdef ABSL_INTERNAL_HAS_CXA_DEMANGLE
902 #error ABSL_INTERNAL_HAS_CXA_DEMANGLE cannot be directly set
903 #elif defined(OS_ANDROID) && (defined(__i386__) || defined(__x86_64__))
904 #define ABSL_INTERNAL_HAS_CXA_DEMANGLE 0
905 #elif defined(__GNUC__) && defined(__GNUC_MINOR__) &&            \
906     (__GNUC__ >= 4 || (__GNUC__ >= 3 && __GNUC_MINOR__ >= 4)) && \
907     !defined(__mips__)
908 #define ABSL_INTERNAL_HAS_CXA_DEMANGLE 1
909 #elif defined(__clang__) && !defined(_MSC_VER)
910 #define ABSL_INTERNAL_HAS_CXA_DEMANGLE 1
911 #endif
912 
913 // ABSL_INTERNAL_HAVE_SSE is used for compile-time detection of SSE support.
914 // See https://gcc.gnu.org/onlinedocs/gcc/x86-Options.html for an overview of
915 // which architectures support the various x86 instruction sets.
916 #ifdef ABSL_INTERNAL_HAVE_SSE
917 #error ABSL_INTERNAL_HAVE_SSE cannot be directly set
918 #elif defined(__SSE__)
919 #define ABSL_INTERNAL_HAVE_SSE 1
920 #elif (defined(_M_X64) || (defined(_M_IX86_FP) && _M_IX86_FP >= 1)) && \
921     !defined(_M_ARM64EC)
922 // MSVC only defines _M_IX86_FP for x86 32-bit code, and _M_IX86_FP >= 1
923 // indicates that at least SSE was targeted with the /arch:SSE option.
924 // All x86-64 processors support SSE, so support can be assumed.
925 // https://docs.microsoft.com/en-us/cpp/preprocessor/predefined-macros
926 #define ABSL_INTERNAL_HAVE_SSE 1
927 #endif
928 
929 // ABSL_INTERNAL_HAVE_SSE2 is used for compile-time detection of SSE2 support.
930 // See https://gcc.gnu.org/onlinedocs/gcc/x86-Options.html for an overview of
931 // which architectures support the various x86 instruction sets.
932 #ifdef ABSL_INTERNAL_HAVE_SSE2
933 #error ABSL_INTERNAL_HAVE_SSE2 cannot be directly set
934 #elif defined(__SSE2__)
935 #define ABSL_INTERNAL_HAVE_SSE2 1
936 #elif (defined(_M_X64) || (defined(_M_IX86_FP) && _M_IX86_FP >= 2)) && \
937     !defined(_M_ARM64EC)
938 // MSVC only defines _M_IX86_FP for x86 32-bit code, and _M_IX86_FP >= 2
939 // indicates that at least SSE2 was targeted with the /arch:SSE2 option.
940 // All x86-64 processors support SSE2, so support can be assumed.
941 // https://docs.microsoft.com/en-us/cpp/preprocessor/predefined-macros
942 #define ABSL_INTERNAL_HAVE_SSE2 1
943 #endif
944 
945 // ABSL_INTERNAL_HAVE_SSSE3 is used for compile-time detection of SSSE3 support.
946 // See https://gcc.gnu.org/onlinedocs/gcc/x86-Options.html for an overview of
947 // which architectures support the various x86 instruction sets.
948 //
949 // MSVC does not have a mode that targets SSSE3 at compile-time. To use SSSE3
950 // with MSVC requires either assuming that the code will only every run on CPUs
951 // that support SSSE3, otherwise __cpuid() can be used to detect support at
952 // runtime and fallback to a non-SSSE3 implementation when SSSE3 is unsupported
953 // by the CPU.
954 #ifdef ABSL_INTERNAL_HAVE_SSSE3
955 #error ABSL_INTERNAL_HAVE_SSSE3 cannot be directly set
956 #elif defined(__SSSE3__)
957 #define ABSL_INTERNAL_HAVE_SSSE3 1
958 #endif
959 
960 // ABSL_INTERNAL_HAVE_ARM_NEON is used for compile-time detection of NEON (ARM
961 // SIMD).
962 //
963 // If __CUDA_ARCH__ is defined, then we are compiling CUDA code in device mode.
964 // In device mode, NEON intrinsics are not available, regardless of host
965 // platform.
966 // https://llvm.org/docs/CompileCudaWithLLVM.html#detecting-clang-vs-nvcc-from-code
967 #ifdef ABSL_INTERNAL_HAVE_ARM_NEON
968 #error ABSL_INTERNAL_HAVE_ARM_NEON cannot be directly set
969 #elif defined(__ARM_NEON) && !defined(__CUDA_ARCH__)
970 #define ABSL_INTERNAL_HAVE_ARM_NEON 1
971 #endif
972 
973 // ABSL_HAVE_CONSTANT_EVALUATED is used for compile-time detection of
974 // constant evaluation support through `absl::is_constant_evaluated`.
975 #ifdef ABSL_HAVE_CONSTANT_EVALUATED
976 #error ABSL_HAVE_CONSTANT_EVALUATED cannot be directly set
977 #endif
978 #ifdef __cpp_lib_is_constant_evaluated
979 #define ABSL_HAVE_CONSTANT_EVALUATED 1
980 #elif ABSL_HAVE_BUILTIN(__builtin_is_constant_evaluated)
981 #define ABSL_HAVE_CONSTANT_EVALUATED 1
982 #endif
983 
984 // ABSL_INTERNAL_EMSCRIPTEN_VERSION combines Emscripten's three version macros
985 // into an integer that can be compared against.
986 #ifdef ABSL_INTERNAL_EMSCRIPTEN_VERSION
987 #error ABSL_INTERNAL_EMSCRIPTEN_VERSION cannot be directly set
988 #endif
989 #ifdef __EMSCRIPTEN__
990 #include <emscripten/version.h>
991 #ifdef __EMSCRIPTEN_major__
992 #if __EMSCRIPTEN_minor__ >= 1000
993 #error __EMSCRIPTEN_minor__ is too big to fit in ABSL_INTERNAL_EMSCRIPTEN_VERSION
994 #endif
995 #if __EMSCRIPTEN_tiny__ >= 1000
996 #error __EMSCRIPTEN_tiny__ is too big to fit in ABSL_INTERNAL_EMSCRIPTEN_VERSION
997 #endif
998 #define ABSL_INTERNAL_EMSCRIPTEN_VERSION                              \
999   ((__EMSCRIPTEN_major__) * 1000000 + (__EMSCRIPTEN_minor__) * 1000 + \
1000    (__EMSCRIPTEN_tiny__))
1001 #endif
1002 #endif
1003 
1004 #endif  // ABSL_BASE_CONFIG_H_
1005