xref: /freebsd/contrib/llvm-project/libcxx/include/__configuration/availability.h (revision 0fca6ea1d4eea4c934cfff25ac9ee8ad6fe95583)
1 // -*- C++ -*-
2 //===----------------------------------------------------------------------===//
3 //
4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5 // See https://llvm.org/LICENSE.txt for license information.
6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #ifndef _LIBCPP___CONFIGURATION_AVAILABILITY_H
11 #define _LIBCPP___CONFIGURATION_AVAILABILITY_H
12 
13 #include <__configuration/compiler.h>
14 #include <__configuration/language.h>
15 
16 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
17 #  pragma GCC system_header
18 #endif
19 
20 // Libc++ is shipped by various vendors. In particular, it is used as a system
21 // library on macOS, iOS and other Apple platforms. In order for users to be
22 // able to compile a binary that is intended to be deployed to an older version
23 // of a platform, Clang provides availability attributes [1]. These attributes
24 // can be placed on declarations and are used to describe the life cycle of a
25 // symbol in the library.
26 //
27 // The main goal is to ensure a compile-time error if a symbol that hasn't been
28 // introduced in a previously released library is used in a program that targets
29 // that previously released library. Normally, this would be a load-time error
30 // when one tries to launch the program against the older library.
31 //
32 // For example, the filesystem library was introduced in the dylib in LLVM 9.
33 // On Apple platforms, this corresponds to macOS 10.15. If a user compiles on
34 // a macOS 10.15 host but targets macOS 10.13 with their program, the compiler
35 // would normally not complain (because the required declarations are in the
36 // headers), but the dynamic loader would fail to find the symbols when actually
37 // trying to launch the program on macOS 10.13. To turn this into a compile-time
38 // issue instead, declarations are annotated with when they were introduced, and
39 // the compiler can produce a diagnostic if the program references something that
40 // isn't available on the deployment target.
41 //
42 // This mechanism is general in nature, and any vendor can add their markup to
43 // the library (see below). Whenever a new feature is added that requires support
44 // in the shared library, two macros are added below to allow marking the feature
45 // as unavailable:
46 // 1. A macro named `_LIBCPP_AVAILABILITY_HAS_<feature>` which must be defined
47 //    to `_LIBCPP_INTRODUCED_IN_<version>` for the appropriate LLVM version.
48 // 2. A macro named `_LIBCPP_AVAILABILITY_<feature>`, which must be defined to
49 //    `_LIBCPP_INTRODUCED_IN_<version>_MARKUP` for the appropriate LLVM version.
50 //
51 // When vendors decide to ship the feature as part of their shared library, they
52 // can update the `_LIBCPP_INTRODUCED_IN_<version>` macro (and the markup counterpart)
53 // based on the platform version they shipped that version of LLVM in. The library
54 // will then use this markup to provide an optimal user experience on these platforms.
55 //
56 // Furthermore, many features in the standard library have corresponding
57 // feature-test macros. The `_LIBCPP_AVAILABILITY_HAS_<feature>` macros
58 // are checked by the corresponding feature-test macros generated by
59 // generate_feature_test_macro_components.py to ensure that the library
60 // doesn't announce a feature as being implemented if it is unavailable on
61 // the deployment target.
62 //
63 // Note that this mechanism is disabled by default in the "upstream" libc++.
64 // Availability annotations are only meaningful when shipping libc++ inside
65 // a platform (i.e. as a system library), and so vendors that want them should
66 // turn those annotations on at CMake configuration time.
67 //
68 // [1]: https://clang.llvm.org/docs/AttributeReference.html#availability
69 
70 // For backwards compatibility, allow users to define _LIBCPP_DISABLE_AVAILABILITY
71 // for a while.
72 #if defined(_LIBCPP_DISABLE_AVAILABILITY)
73 #  if !defined(_LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS)
74 #    define _LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS
75 #  endif
76 #endif
77 
78 // Availability markup is disabled when building the library, or when a non-Clang
79 // compiler is used because only Clang supports the necessary attributes.
80 #if defined(_LIBCPP_BUILDING_LIBRARY) || defined(_LIBCXXABI_BUILDING_LIBRARY) || !defined(_LIBCPP_COMPILER_CLANG_BASED)
81 #  if !defined(_LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS)
82 #    define _LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS
83 #  endif
84 #endif
85 
86 // When availability annotations are disabled, we take for granted that features introduced
87 // in all versions of the library are available.
88 #if defined(_LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS)
89 
90 #  define _LIBCPP_INTRODUCED_IN_LLVM_19 1
91 #  define _LIBCPP_INTRODUCED_IN_LLVM_19_ATTRIBUTE /* nothing */
92 
93 #  define _LIBCPP_INTRODUCED_IN_LLVM_18 1
94 #  define _LIBCPP_INTRODUCED_IN_LLVM_18_ATTRIBUTE /* nothing */
95 
96 #  define _LIBCPP_INTRODUCED_IN_LLVM_17 1
97 #  define _LIBCPP_INTRODUCED_IN_LLVM_17_ATTRIBUTE /* nothing */
98 
99 #  define _LIBCPP_INTRODUCED_IN_LLVM_16 1
100 #  define _LIBCPP_INTRODUCED_IN_LLVM_16_ATTRIBUTE /* nothing */
101 
102 #  define _LIBCPP_INTRODUCED_IN_LLVM_15 1
103 #  define _LIBCPP_INTRODUCED_IN_LLVM_15_ATTRIBUTE /* nothing */
104 
105 #  define _LIBCPP_INTRODUCED_IN_LLVM_14 1
106 #  define _LIBCPP_INTRODUCED_IN_LLVM_14_ATTRIBUTE /* nothing */
107 
108 #  define _LIBCPP_INTRODUCED_IN_LLVM_13 1
109 #  define _LIBCPP_INTRODUCED_IN_LLVM_13_ATTRIBUTE /* nothing */
110 
111 #  define _LIBCPP_INTRODUCED_IN_LLVM_12 1
112 #  define _LIBCPP_INTRODUCED_IN_LLVM_12_ATTRIBUTE /* nothing */
113 
114 #  define _LIBCPP_INTRODUCED_IN_LLVM_11 1
115 #  define _LIBCPP_INTRODUCED_IN_LLVM_11_ATTRIBUTE /* nothing */
116 
117 #  define _LIBCPP_INTRODUCED_IN_LLVM_10 1
118 #  define _LIBCPP_INTRODUCED_IN_LLVM_10_ATTRIBUTE /* nothing */
119 
120 #  define _LIBCPP_INTRODUCED_IN_LLVM_9 1
121 #  define _LIBCPP_INTRODUCED_IN_LLVM_9_ATTRIBUTE      /* nothing */
122 #  define _LIBCPP_INTRODUCED_IN_LLVM_9_ATTRIBUTE_PUSH /* nothing */
123 #  define _LIBCPP_INTRODUCED_IN_LLVM_9_ATTRIBUTE_POP  /* nothing */
124 
125 #  define _LIBCPP_INTRODUCED_IN_LLVM_8 1
126 #  define _LIBCPP_INTRODUCED_IN_LLVM_8_ATTRIBUTE /* nothing */
127 
128 #  define _LIBCPP_INTRODUCED_IN_LLVM_4 1
129 #  define _LIBCPP_INTRODUCED_IN_LLVM_4_ATTRIBUTE /* nothing */
130 
131 #elif defined(__APPLE__)
132 
133 // clang-format off
134 
135 // LLVM 19
136 // TODO: Fill this in
137 #  define _LIBCPP_INTRODUCED_IN_LLVM_19 0
138 #  define _LIBCPP_INTRODUCED_IN_LLVM_19_ATTRIBUTE __attribute__((unavailable))
139 
140 // LLVM 18
141 // TODO: Fill this in
142 #  define _LIBCPP_INTRODUCED_IN_LLVM_18 0
143 #  define _LIBCPP_INTRODUCED_IN_LLVM_18_ATTRIBUTE __attribute__((unavailable))
144 
145 // LLVM 17
146 #  if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 140400) ||       \
147       (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 170400) ||     \
148       (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 170400) ||             \
149       (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 100400)
150 #    define _LIBCPP_INTRODUCED_IN_LLVM_17 0
151 #  else
152 #    define _LIBCPP_INTRODUCED_IN_LLVM_17 1
153 #  endif
154 #  define _LIBCPP_INTRODUCED_IN_LLVM_17_ATTRIBUTE                                                                 \
155     __attribute__((availability(macos, strict, introduced = 14.4)))                                               \
156     __attribute__((availability(ios, strict, introduced = 17.4)))                                                 \
157     __attribute__((availability(tvos, strict, introduced = 17.4)))                                                \
158     __attribute__((availability(watchos, strict, introduced = 10.4)))
159 
160 // LLVM 16
161 #  if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 140000) ||       \
162       (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 170000) ||     \
163       (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 170000) ||             \
164       (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 100000)
165 #    define _LIBCPP_INTRODUCED_IN_LLVM_16 0
166 #  else
167 #    define _LIBCPP_INTRODUCED_IN_LLVM_16 1
168 #  endif
169 #  define _LIBCPP_INTRODUCED_IN_LLVM_16_ATTRIBUTE                                                                 \
170     __attribute__((availability(macos, strict, introduced = 14.0)))                                               \
171     __attribute__((availability(ios, strict, introduced = 17.0)))                                                 \
172     __attribute__((availability(tvos, strict, introduced = 17.0)))                                                \
173     __attribute__((availability(watchos, strict, introduced = 10.0)))
174 
175 // LLVM 15
176 #  if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 130400) ||   \
177       (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 160500) || \
178       (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 160500) ||         \
179       (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 90500)
180 #    define _LIBCPP_INTRODUCED_IN_LLVM_15 0
181 #  else
182 #    define _LIBCPP_INTRODUCED_IN_LLVM_15 1
183 #  endif
184 #  define _LIBCPP_INTRODUCED_IN_LLVM_15_ATTRIBUTE                                                                 \
185     __attribute__((availability(macos, strict, introduced = 13.4)))                                               \
186     __attribute__((availability(ios, strict, introduced = 16.5)))                                                 \
187     __attribute__((availability(tvos, strict, introduced = 16.5)))                                                \
188     __attribute__((availability(watchos, strict, introduced = 9.5)))
189 
190 // LLVM 14
191 #  define _LIBCPP_INTRODUCED_IN_LLVM_14 _LIBCPP_INTRODUCED_IN_LLVM_15
192 #  define _LIBCPP_INTRODUCED_IN_LLVM_14_ATTRIBUTE _LIBCPP_INTRODUCED_IN_LLVM_15_ATTRIBUTE
193 
194 // LLVM 13
195 #  if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 130000) ||   \
196       (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 160000) || \
197       (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 160000) ||         \
198       (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 90000)
199 #    define _LIBCPP_INTRODUCED_IN_LLVM_13 0
200 #  else
201 #    define _LIBCPP_INTRODUCED_IN_LLVM_13 1
202 #  endif
203 #  define _LIBCPP_INTRODUCED_IN_LLVM_13_ATTRIBUTE                                                                 \
204     __attribute__((availability(macos, strict, introduced = 13.0)))                                               \
205     __attribute__((availability(ios, strict, introduced = 16.0)))                                                 \
206     __attribute__((availability(tvos, strict, introduced = 16.0)))                                                \
207     __attribute__((availability(watchos, strict, introduced = 9.0)))
208 
209 // LLVM 12
210 #  if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 120300)   ||     \
211       (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 150300) ||     \
212       (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 150300)         ||     \
213       (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 80300)
214 #    define _LIBCPP_INTRODUCED_IN_LLVM_12 0
215 #  else
216 #    define _LIBCPP_INTRODUCED_IN_LLVM_12 1
217 #  endif
218 #  define _LIBCPP_INTRODUCED_IN_LLVM_12_ATTRIBUTE                                                                 \
219     __attribute__((availability(macos, strict, introduced = 12.3)))                                               \
220     __attribute__((availability(ios, strict, introduced = 15.3)))                                                 \
221     __attribute__((availability(tvos, strict, introduced = 15.3)))                                                \
222     __attribute__((availability(watchos, strict, introduced = 8.3)))
223 
224 // LLVM 11
225 #  if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 110000) ||   \
226       (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 140000) || \
227       (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 140000) ||         \
228       (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 70000)
229 #    define _LIBCPP_INTRODUCED_IN_LLVM_11 0
230 #  else
231 #    define _LIBCPP_INTRODUCED_IN_LLVM_11 1
232 #  endif
233 #  define _LIBCPP_INTRODUCED_IN_LLVM_11_ATTRIBUTE                                                                 \
234     __attribute__((availability(macos, strict, introduced = 11.0)))                                               \
235     __attribute__((availability(ios, strict, introduced = 14.0)))                                                 \
236     __attribute__((availability(tvos, strict, introduced = 14.0)))                                                \
237     __attribute__((availability(watchos, strict, introduced = 7.0)))
238 
239 // LLVM 10
240 #  define _LIBCPP_INTRODUCED_IN_LLVM_10 _LIBCPP_INTRODUCED_IN_LLVM_11
241 #  define _LIBCPP_INTRODUCED_IN_LLVM_10_ATTRIBUTE _LIBCPP_INTRODUCED_IN_LLVM_11_ATTRIBUTE
242 
243 // LLVM 9
244 #  if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101500) ||   \
245       (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 130000) || \
246       (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 130000) ||         \
247       (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 60000)
248 #    define _LIBCPP_INTRODUCED_IN_LLVM_9 0
249 #  else
250 #    define _LIBCPP_INTRODUCED_IN_LLVM_9 1
251 #  endif
252 #  define _LIBCPP_INTRODUCED_IN_LLVM_9_ATTRIBUTE                                                                  \
253     __attribute__((availability(macos, strict, introduced = 10.15)))                                              \
254     __attribute__((availability(ios, strict, introduced = 13.0)))                                                 \
255     __attribute__((availability(tvos, strict, introduced = 13.0)))                                                \
256     __attribute__((availability(watchos, strict, introduced = 6.0)))
257 #  define _LIBCPP_INTRODUCED_IN_LLVM_9_ATTRIBUTE_PUSH                                                                            \
258     _Pragma("clang attribute push(__attribute__((availability(macos,strict,introduced=10.15))), apply_to=any(function,record))") \
259     _Pragma("clang attribute push(__attribute__((availability(ios,strict,introduced=13.0))), apply_to=any(function,record))")    \
260     _Pragma("clang attribute push(__attribute__((availability(tvos,strict,introduced=13.0))), apply_to=any(function,record))")   \
261     _Pragma("clang attribute push(__attribute__((availability(watchos,strict,introduced=6.0))), apply_to=any(function,record))")
262 #  define _LIBCPP_INTRODUCED_IN_LLVM_9_ATTRIBUTE_POP                                                                    \
263     _Pragma("clang attribute pop") \
264     _Pragma("clang attribute pop") \
265     _Pragma("clang attribute pop") \
266     _Pragma("clang attribute pop")
267 
268 // LLVM 4
269 #  if defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 50000
270 #    define _LIBCPP_INTRODUCED_IN_LLVM_4 0
271 #  else
272 #    define _LIBCPP_INTRODUCED_IN_LLVM_4 1
273 #  endif
274 #  define _LIBCPP_INTRODUCED_IN_LLVM_4_ATTRIBUTE __attribute__((availability(watchos, strict, introduced = 5.0)))
275 
276 // clang-format on
277 
278 #else
279 
280 // ...New vendors can add availability markup here...
281 
282 #  error                                                                                                               \
283       "It looks like you're trying to enable vendor availability markup, but you haven't defined the corresponding macros yet!"
284 
285 #endif
286 
287 // These macros control the availability of std::bad_optional_access and
288 // other exception types. These were put in the shared library to prevent
289 // code bloat from every user program defining the vtable for these exception
290 // types.
291 //
292 // Note that when exceptions are disabled, the methods that normally throw
293 // these exceptions can be used even on older deployment targets, but those
294 // methods will abort instead of throwing.
295 #define _LIBCPP_AVAILABILITY_HAS_BAD_OPTIONAL_ACCESS _LIBCPP_INTRODUCED_IN_LLVM_4
296 #define _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS _LIBCPP_INTRODUCED_IN_LLVM_4_ATTRIBUTE
297 
298 #define _LIBCPP_AVAILABILITY_HAS_BAD_VARIANT_ACCESS _LIBCPP_INTRODUCED_IN_LLVM_4
299 #define _LIBCPP_AVAILABILITY_BAD_VARIANT_ACCESS _LIBCPP_INTRODUCED_IN_LLVM_4_ATTRIBUTE
300 
301 #define _LIBCPP_AVAILABILITY_HAS_BAD_ANY_CAST _LIBCPP_INTRODUCED_IN_LLVM_4
302 #define _LIBCPP_AVAILABILITY_BAD_ANY_CAST _LIBCPP_INTRODUCED_IN_LLVM_4_ATTRIBUTE
303 
304 // These macros control the availability of all parts of <filesystem> that
305 // depend on something in the dylib.
306 #define _LIBCPP_AVAILABILITY_HAS_FILESYSTEM_LIBRARY _LIBCPP_INTRODUCED_IN_LLVM_9
307 #define _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY _LIBCPP_INTRODUCED_IN_LLVM_9_ATTRIBUTE
308 #define _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY_PUSH _LIBCPP_INTRODUCED_IN_LLVM_9_ATTRIBUTE_PUSH
309 #define _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY_POP _LIBCPP_INTRODUCED_IN_LLVM_9_ATTRIBUTE_POP
310 
311 // This controls the availability of the C++20 synchronization library,
312 // which requires shared library support for various operations
313 // (see libcxx/src/atomic.cpp). This includes <barier>, <latch>,
314 // <semaphore>, and notification functions on std::atomic.
315 #define _LIBCPP_AVAILABILITY_HAS_SYNC _LIBCPP_INTRODUCED_IN_LLVM_11
316 #define _LIBCPP_AVAILABILITY_SYNC _LIBCPP_INTRODUCED_IN_LLVM_11_ATTRIBUTE
317 
318 // Enable additional explicit instantiations of iostreams components. This
319 // reduces the number of weak definitions generated in programs that use
320 // iostreams by providing a single strong definition in the shared library.
321 //
322 // TODO: Enable additional explicit instantiations on GCC once it supports exclude_from_explicit_instantiation,
323 //       or once libc++ doesn't use the attribute anymore.
324 // TODO: Enable them on Windows once https://llvm.org/PR41018 has been fixed.
325 #if !defined(_LIBCPP_COMPILER_GCC) && !defined(_WIN32)
326 #  define _LIBCPP_AVAILABILITY_HAS_ADDITIONAL_IOSTREAM_EXPLICIT_INSTANTIATIONS_1 _LIBCPP_INTRODUCED_IN_LLVM_12
327 #else
328 #  define _LIBCPP_AVAILABILITY_HAS_ADDITIONAL_IOSTREAM_EXPLICIT_INSTANTIATIONS_1 0
329 #endif
330 
331 // This controls the availability of floating-point std::to_chars functions.
332 // These overloads were added later than the integer overloads.
333 #define _LIBCPP_AVAILABILITY_HAS_TO_CHARS_FLOATING_POINT _LIBCPP_INTRODUCED_IN_LLVM_14
334 #define _LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_INTRODUCED_IN_LLVM_14_ATTRIBUTE
335 
336 // This controls whether the library claims to provide a default verbose
337 // termination function, and consequently whether the headers will try
338 // to use it when the mechanism isn't overriden at compile-time.
339 #define _LIBCPP_AVAILABILITY_HAS_VERBOSE_ABORT _LIBCPP_INTRODUCED_IN_LLVM_15
340 #define _LIBCPP_AVAILABILITY_VERBOSE_ABORT _LIBCPP_INTRODUCED_IN_LLVM_15_ATTRIBUTE
341 
342 // This controls the availability of the C++17 std::pmr library,
343 // which is implemented in large part in the built library.
344 //
345 // TODO: Enable std::pmr markup once https://github.com/llvm/llvm-project/issues/40340 has been fixed
346 //       Until then, it is possible for folks to try to use `std::pmr` when back-deploying to targets that don't support
347 //       it and it'll be a load-time error, but we don't have a good alternative because the library won't compile if we
348 //       use availability annotations until that bug has been fixed.
349 #define _LIBCPP_AVAILABILITY_HAS_PMR _LIBCPP_INTRODUCED_IN_LLVM_16
350 #define _LIBCPP_AVAILABILITY_PMR
351 
352 // These macros controls the availability of __cxa_init_primary_exception
353 // in the built library, which std::make_exception_ptr might use
354 // (see libcxx/include/__exception/exception_ptr.h).
355 #define _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION _LIBCPP_INTRODUCED_IN_LLVM_18
356 #define _LIBCPP_AVAILABILITY_INIT_PRIMARY_EXCEPTION _LIBCPP_INTRODUCED_IN_LLVM_18_ATTRIBUTE
357 
358 // This controls the availability of C++23 <print>, which
359 // has a dependency on the built library (it needs access to
360 // the underlying buffer types of std::cout, std::cerr, and std::clog.
361 #define _LIBCPP_AVAILABILITY_HAS_PRINT _LIBCPP_INTRODUCED_IN_LLVM_18
362 #define _LIBCPP_AVAILABILITY_PRINT _LIBCPP_INTRODUCED_IN_LLVM_18_ATTRIBUTE
363 
364 // This controls the availability of the C++20 time zone database.
365 // The parser code is built in the library.
366 #define _LIBCPP_AVAILABILITY_HAS_TZDB _LIBCPP_INTRODUCED_IN_LLVM_19
367 #define _LIBCPP_AVAILABILITY_TZDB _LIBCPP_INTRODUCED_IN_LLVM_19_ATTRIBUTE
368 
369 // These macros determine whether we assume that std::bad_function_call and
370 // std::bad_expected_access provide a key function in the dylib. This allows
371 // centralizing their vtable and typeinfo instead of having all TUs provide
372 // a weak definition that then gets deduplicated.
373 #define _LIBCPP_AVAILABILITY_HAS_BAD_FUNCTION_CALL_KEY_FUNCTION _LIBCPP_INTRODUCED_IN_LLVM_19
374 #define _LIBCPP_AVAILABILITY_BAD_FUNCTION_CALL_KEY_FUNCTION _LIBCPP_INTRODUCED_IN_LLVM_19_ATTRIBUTE
375 #define _LIBCPP_AVAILABILITY_HAS_BAD_EXPECTED_ACCESS_KEY_FUNCTION _LIBCPP_INTRODUCED_IN_LLVM_19
376 #define _LIBCPP_AVAILABILITY_BAD_EXPECTED_ACCESS_KEY_FUNCTION _LIBCPP_INTRODUCED_IN_LLVM_19_ATTRIBUTE
377 
378 // Define availability attributes that depend on _LIBCPP_HAS_NO_EXCEPTIONS.
379 // Those are defined in terms of the availability attributes above, and
380 // should not be vendor-specific.
381 #if defined(_LIBCPP_HAS_NO_EXCEPTIONS)
382 #  define _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST
383 #  define _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS
384 #  define _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS
385 #else
386 #  define _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST _LIBCPP_AVAILABILITY_BAD_ANY_CAST
387 #  define _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS
388 #  define _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS _LIBCPP_AVAILABILITY_BAD_VARIANT_ACCESS
389 #endif
390 
391 // Define availability attributes that depend on both
392 // _LIBCPP_HAS_NO_EXCEPTIONS and _LIBCPP_HAS_NO_RTTI.
393 #if defined(_LIBCPP_HAS_NO_EXCEPTIONS) || defined(_LIBCPP_HAS_NO_RTTI)
394 #  undef _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION
395 #  undef _LIBCPP_AVAILABILITY_INIT_PRIMARY_EXCEPTION
396 #  define _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION 0
397 #  define _LIBCPP_AVAILABILITY_INIT_PRIMARY_EXCEPTION
398 #endif
399 
400 #endif // _LIBCPP___CONFIGURATION_AVAILABILITY_H
401