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___CONFIG
11#define _LIBCPP___CONFIG
12
13#include <__config_site>
14#include <__configuration/abi.h>
15#include <__configuration/availability.h>
16#include <__configuration/compiler.h>
17#include <__configuration/language.h>
18#include <__configuration/platform.h>
19
20#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
21# pragma GCC system_header
22#endif
23
24#ifdef __cplusplus
25
26// The attributes supported by clang are documented at https://clang.llvm.org/docs/AttributeReference.html
27
28// _LIBCPP_VERSION represents the version of libc++, which matches the version of LLVM.
29// Given a LLVM release LLVM XX.YY.ZZ (e.g. LLVM 17.0.1 == 17.00.01), _LIBCPP_VERSION is
30// defined to XXYYZZ.
31# define _LIBCPP_VERSION 210000
32
33# define _LIBCPP_CONCAT_IMPL(_X, _Y) _X##_Y
34# define _LIBCPP_CONCAT(_X, _Y) _LIBCPP_CONCAT_IMPL(_X, _Y)
35# define _LIBCPP_CONCAT3(X, Y, Z) _LIBCPP_CONCAT(X, _LIBCPP_CONCAT(Y, Z))
36
37# if __STDC_HOSTED__ == 0
38# define _LIBCPP_FREESTANDING
39# endif
40
41// HARDENING {
42
43// TODO: Remove in LLVM 21. We're making this an error to catch folks who might not have migrated.
44# ifdef _LIBCPP_ENABLE_ASSERTIONS
45# error "_LIBCPP_ENABLE_ASSERTIONS has been removed, please use _LIBCPP_HARDENING_MODE instead"
46# endif
47
48// The library provides the macro `_LIBCPP_HARDENING_MODE` which can be set to one of the following values:
49//
50// - `_LIBCPP_HARDENING_MODE_NONE`;
51// - `_LIBCPP_HARDENING_MODE_FAST`;
52// - `_LIBCPP_HARDENING_MODE_EXTENSIVE`;
53// - `_LIBCPP_HARDENING_MODE_DEBUG`.
54//
55// These values have the following effects:
56//
57// - `_LIBCPP_HARDENING_MODE_NONE` -- sets the hardening mode to "none" which disables all runtime hardening checks;
58//
59// - `_LIBCPP_HARDENING_MODE_FAST` -- sets that hardening mode to "fast". The fast mode enables security-critical checks
60// that can be done with relatively little runtime overhead in constant time;
61//
62// - `_LIBCPP_HARDENING_MODE_EXTENSIVE` -- sets the hardening mode to "extensive". The extensive mode is a superset of
63// the fast mode that additionally enables checks that are relatively cheap and prevent common types of logic errors
64// but are not necessarily security-critical;
65//
66// - `_LIBCPP_HARDENING_MODE_DEBUG` -- sets the hardening mode to "debug". The debug mode is a superset of the extensive
67// mode and enables all checks available in the library, including internal assertions. Checks that are part of the
68// debug mode can be very expensive and thus the debug mode is intended to be used for testing, not in production.
69
70// Inside the library, assertions are categorized so they can be cherry-picked based on the chosen hardening mode. These
71// macros are only for internal use -- users should only pick one of the high-level hardening modes described above.
72//
73// - `_LIBCPP_ASSERT_VALID_INPUT_RANGE` -- checks that ranges (whether expressed as an iterator pair, an iterator and
74// a sentinel, an iterator and a count, or a `std::range`) given as input to library functions are valid:
75// - the sentinel is reachable from the begin iterator;
76// - TODO(hardening): both iterators refer to the same container.
77//
78// - `_LIBCPP_ASSERT_VALID_ELEMENT_ACCESS` -- checks that any attempts to access a container element, whether through
79// the container object or through an iterator, are valid and do not attempt to go out of bounds or otherwise access
80// a non-existent element. For iterator checks to work, bounded iterators must be enabled in the ABI. Types like
81// `optional` and `function` are considered one-element containers for the purposes of this check.
82//
83// - `_LIBCPP_ASSERT_NON_NULL` -- checks that the pointer being dereferenced is not null. On most modern platforms zero
84// address does not refer to an actual location in memory, so a null pointer dereference would not compromize the
85// memory security of a program (however, it is still undefined behavior that can result in strange errors due to
86// compiler optimizations).
87//
88// - `_LIBCPP_ASSERT_NON_OVERLAPPING_RANGES` -- for functions that take several ranges as arguments, checks that the
89// given ranges do not overlap.
90//
91// - `_LIBCPP_ASSERT_VALID_DEALLOCATION` -- checks that an attempt to deallocate memory is valid (e.g. the given object
92// was allocated by the given allocator). Violating this category typically results in a memory leak.
93//
94// - `_LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL` -- checks that a call to an external API doesn't fail in
95// an unexpected manner. This includes triggering documented cases of undefined behavior in an external library (like
96// attempting to unlock an unlocked mutex in pthreads). Any API external to the library falls under this category
97// (from system calls to compiler intrinsics). We generally don't expect these failures to compromize memory safety or
98// otherwise create an immediate security issue.
99//
100// - `_LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR` -- checks any operations that exchange nodes between containers to make sure
101// the containers have compatible allocators.
102//
103// - `_LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN` -- checks that the given argument is within the domain of valid arguments
104// for the function. Violating this typically produces an incorrect result (e.g. the clamp algorithm returns the
105// original value without clamping it due to incorrect functors) or puts an object into an invalid state (e.g.
106// a string view where only a subset of elements is possible to access). This category is for assertions violating
107// which doesn't cause any immediate issues in the library -- whatever the consequences are, they will happen in the
108// user code.
109//
110// - `_LIBCPP_ASSERT_PEDANTIC` -- checks prerequisites which are imposed by the Standard, but violating which happens to
111// be benign in our implementation.
112//
113// - `_LIBCPP_ASSERT_SEMANTIC_REQUIREMENT` -- checks that the given argument satisfies the semantic requirements imposed
114// by the Standard. Typically, there is no simple way to completely prove that a semantic requirement is satisfied;
115// thus, this would often be a heuristic check and it might be quite expensive.
116//
117// - `_LIBCPP_ASSERT_INTERNAL` -- checks that internal invariants of the library hold. These assertions don't depend on
118// user input.
119//
120// - `_LIBCPP_ASSERT_UNCATEGORIZED` -- for assertions that haven't been properly classified yet.
121
122// clang-format off
123# define _LIBCPP_HARDENING_MODE_NONE (1 << 1)
124# define _LIBCPP_HARDENING_MODE_FAST (1 << 2)
125# define _LIBCPP_HARDENING_MODE_EXTENSIVE (1 << 4) // Deliberately not ordered.
126# define _LIBCPP_HARDENING_MODE_DEBUG (1 << 3)
127// clang-format on
128
129# ifndef _LIBCPP_HARDENING_MODE
130
131# ifndef _LIBCPP_HARDENING_MODE_DEFAULT
132# error _LIBCPP_HARDENING_MODE_DEFAULT is not defined. This definition should be set at configuration time in the \
133`__config_site` header, please make sure your installation of libc++ is not broken.
134# endif
135
136# define _LIBCPP_HARDENING_MODE _LIBCPP_HARDENING_MODE_DEFAULT
137# endif
138
139# if _LIBCPP_HARDENING_MODE != _LIBCPP_HARDENING_MODE_NONE && \
140 _LIBCPP_HARDENING_MODE != _LIBCPP_HARDENING_MODE_FAST && \
141 _LIBCPP_HARDENING_MODE != _LIBCPP_HARDENING_MODE_EXTENSIVE && \
142 _LIBCPP_HARDENING_MODE != _LIBCPP_HARDENING_MODE_DEBUG
143# error _LIBCPP_HARDENING_MODE must be set to one of the following values: \
144_LIBCPP_HARDENING_MODE_NONE, \
145_LIBCPP_HARDENING_MODE_FAST, \
146_LIBCPP_HARDENING_MODE_EXTENSIVE, \
147_LIBCPP_HARDENING_MODE_DEBUG
148# endif
149
150// } HARDENING
151
152# define _LIBCPP_TOSTRING2(x) #x
153# define _LIBCPP_TOSTRING(x) _LIBCPP_TOSTRING2(x)
154
155// NOLINTNEXTLINE(libcpp-cpp-version-check)
156# if __cplusplus < 201103L
157# define _LIBCPP_CXX03_LANG
158# endif
159
160# ifndef __has_constexpr_builtin
161# define __has_constexpr_builtin(x) 0
162# endif
163
164// This checks wheter a Clang module is built
165# ifndef __building_module
166# define __building_module(...) 0
167# endif
168
169// '__is_identifier' returns '0' if '__x' is a reserved identifier provided by
170// the compiler and '1' otherwise.
171# ifndef __is_identifier
172# define __is_identifier(__x) 1
173# endif
174
175# ifndef __has_declspec_attribute
176# define __has_declspec_attribute(__x) 0
177# endif
178
179# define __has_keyword(__x) !(__is_identifier(__x))
180
181# ifndef __has_warning
182# define __has_warning(...) 0
183# endif
184
185# if !defined(_LIBCPP_COMPILER_CLANG_BASED) && __cplusplus < 201103L
186# error "libc++ only supports C++03 with Clang-based compilers. Please enable C++11"
187# endif
188
189# if defined(_LIBCPP_ABI_MICROSOFT) && !defined(_LIBCPP_NO_VCRUNTIME)
190# define _LIBCPP_ABI_VCRUNTIME
191# endif
192
193# if __has_feature(experimental_library)
194# ifndef _LIBCPP_ENABLE_EXPERIMENTAL
195# define _LIBCPP_ENABLE_EXPERIMENTAL
196# endif
197# endif
198
199// Incomplete features get their own specific disabling flags. This makes it
200// easier to grep for target specific flags once the feature is complete.
201# if defined(_LIBCPP_ENABLE_EXPERIMENTAL) || defined(_LIBCPP_BUILDING_LIBRARY)
202# define _LIBCPP_HAS_EXPERIMENTAL_LIBRARY 1
203# else
204# define _LIBCPP_HAS_EXPERIMENTAL_LIBRARY 0
205# endif
206
207# define _LIBCPP_HAS_EXPERIMENTAL_PSTL _LIBCPP_HAS_EXPERIMENTAL_LIBRARY
208# define _LIBCPP_HAS_EXPERIMENTAL_TZDB _LIBCPP_HAS_EXPERIMENTAL_LIBRARY
209# define _LIBCPP_HAS_EXPERIMENTAL_SYNCSTREAM _LIBCPP_HAS_EXPERIMENTAL_LIBRARY
210
211# if defined(__MVS__)
212# include <features.h> // for __NATIVE_ASCII_F
213# endif
214
215# if defined(_WIN32)
216# define _LIBCPP_WIN32API
217# define _LIBCPP_SHORT_WCHAR 1
218// Both MinGW and native MSVC provide a "MSVC"-like environment
219# define _LIBCPP_MSVCRT_LIKE
220// If mingw not explicitly detected, assume using MS C runtime only if
221// a MS compatibility version is specified.
222# if defined(_MSC_VER) && !defined(__MINGW32__)
223# define _LIBCPP_MSVCRT // Using Microsoft's C Runtime library
224# endif
225# if (defined(_M_AMD64) || defined(__x86_64__)) || (defined(_M_ARM) || defined(__arm__))
226# define _LIBCPP_HAS_BITSCAN64 1
227# else
228# define _LIBCPP_HAS_BITSCAN64 0
229# endif
230# define _LIBCPP_HAS_OPEN_WITH_WCHAR 1
231# else
232# define _LIBCPP_HAS_OPEN_WITH_WCHAR 0
233# define _LIBCPP_HAS_BITSCAN64 0
234# endif // defined(_WIN32)
235
236# if defined(_AIX) && !defined(__64BIT__)
237// The size of wchar is 2 byte on 32-bit mode on AIX.
238# define _LIBCPP_SHORT_WCHAR 1
239# endif
240
241// Libc++ supports various implementations of std::random_device.
242//
243// _LIBCPP_USING_DEV_RANDOM
244// Read entropy from the given file, by default `/dev/urandom`.
245// If a token is provided, it is assumed to be the path to a file
246// to read entropy from. This is the default behavior if nothing
247// else is specified. This implementation requires storing state
248// inside `std::random_device`.
249//
250// _LIBCPP_USING_ARC4_RANDOM
251// Use arc4random(). This allows obtaining random data even when
252// using sandboxing mechanisms. On some platforms like Apple, this
253// is the recommended source of entropy for user-space programs.
254// When this option is used, the token passed to `std::random_device`'s
255// constructor *must* be "/dev/urandom" -- anything else is an error.
256//
257// _LIBCPP_USING_GETENTROPY
258// Use getentropy().
259// When this option is used, the token passed to `std::random_device`'s
260// constructor *must* be "/dev/urandom" -- anything else is an error.
261//
262// _LIBCPP_USING_FUCHSIA_CPRNG
263// Use Fuchsia's zx_cprng_draw() system call, which is specified to
264// deliver high-quality entropy and cannot fail.
265// When this option is used, the token passed to `std::random_device`'s
266// constructor *must* be "/dev/urandom" -- anything else is an error.
267//
268// _LIBCPP_USING_NACL_RANDOM
269// NaCl's sandbox (which PNaCl also runs in) doesn't allow filesystem access,
270// including accesses to the special files under `/dev`. This implementation
271// uses the NaCL syscall `nacl_secure_random_init()` to get entropy.
272// When this option is used, the token passed to `std::random_device`'s
273// constructor *must* be "/dev/urandom" -- anything else is an error.
274//
275// _LIBCPP_USING_WIN32_RANDOM
276// Use rand_s(), for use on Windows.
277// When this option is used, the token passed to `std::random_device`'s
278// constructor *must* be "/dev/urandom" -- anything else is an error.
279# if defined(__APPLE__) || defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) || \
280 defined(__DragonFly__)
281# define _LIBCPP_USING_ARC4_RANDOM
282# elif defined(__wasi__) || defined(__EMSCRIPTEN__)
283# define _LIBCPP_USING_GETENTROPY
284# elif defined(__Fuchsia__)
285# define _LIBCPP_USING_FUCHSIA_CPRNG
286# elif defined(__native_client__)
287# define _LIBCPP_USING_NACL_RANDOM
288# elif defined(_LIBCPP_WIN32API)
289# define _LIBCPP_USING_WIN32_RANDOM
290# else
291# define _LIBCPP_USING_DEV_RANDOM
292# endif
293
294# ifndef _LIBCPP_CXX03_LANG
295
296# define _LIBCPP_ALIGNOF(_Tp) alignof(_Tp)
297# define _ALIGNAS_TYPE(x) alignas(x)
298# define _ALIGNAS(x) alignas(x)
299# define _NOEXCEPT noexcept
300# define _NOEXCEPT_(...) noexcept(__VA_ARGS__)
301# define _LIBCPP_CONSTEXPR constexpr
302
303# else
304
305# define _LIBCPP_ALIGNOF(_Tp) _Alignof(_Tp)
306# define _ALIGNAS_TYPE(x) __attribute__((__aligned__(_LIBCPP_ALIGNOF(x))))
307# define _ALIGNAS(x) __attribute__((__aligned__(x)))
308# define nullptr __nullptr
309# define _NOEXCEPT throw()
310# define _NOEXCEPT_(...)
311# define static_assert(...) _Static_assert(__VA_ARGS__)
312# define decltype(...) __decltype(__VA_ARGS__)
313# define _LIBCPP_CONSTEXPR
314
315typedef __char16_t char16_t;
316typedef __char32_t char32_t;
317
318# endif
319
320# define _LIBCPP_PREFERRED_ALIGNOF(_Tp) __alignof(_Tp)
321
322# if __has_extension(blocks) && defined(__APPLE__)
323# define _LIBCPP_HAS_BLOCKS_RUNTIME 1
324# else
325# define _LIBCPP_HAS_BLOCKS_RUNTIME 0
326# endif
327
328# define _LIBCPP_ALWAYS_INLINE __attribute__((__always_inline__))
329
330# if defined(_LIBCPP_OBJECT_FORMAT_COFF)
331
332# ifdef _DLL
333# define _LIBCPP_CRT_FUNC __declspec(dllimport)
334# else
335# define _LIBCPP_CRT_FUNC
336# endif
337
338# if defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS) || (defined(__MINGW32__) && !defined(_LIBCPP_BUILDING_LIBRARY))
339# define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS
340# define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS
341# define _LIBCPP_OVERRIDABLE_FUNC_VIS
342# define _LIBCPP_EXPORTED_FROM_ABI
343# elif defined(_LIBCPP_BUILDING_LIBRARY)
344# if defined(__MINGW32__)
345# define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS __declspec(dllexport)
346# define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS
347# else
348# define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS
349# define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS __declspec(dllexport)
350# endif
351# define _LIBCPP_OVERRIDABLE_FUNC_VIS __declspec(dllexport)
352# define _LIBCPP_EXPORTED_FROM_ABI __declspec(dllexport)
353# else
354# define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS __declspec(dllimport)
355# define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS
356# define _LIBCPP_OVERRIDABLE_FUNC_VIS
357# define _LIBCPP_EXPORTED_FROM_ABI __declspec(dllimport)
358# endif
359
360# define _LIBCPP_HIDDEN
361# define _LIBCPP_TEMPLATE_DATA_VIS
362# define _LIBCPP_NAMESPACE_VISIBILITY
363
364# else
365
366# if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
367# define _LIBCPP_VISIBILITY(vis) __attribute__((__visibility__(vis)))
368# else
369# define _LIBCPP_VISIBILITY(vis)
370# endif
371
372# define _LIBCPP_HIDDEN _LIBCPP_VISIBILITY("hidden")
373# define _LIBCPP_TEMPLATE_DATA_VIS _LIBCPP_VISIBILITY("default")
374# define _LIBCPP_EXPORTED_FROM_ABI _LIBCPP_VISIBILITY("default")
375# define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS _LIBCPP_VISIBILITY("default")
376# define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS
377
378// TODO: Make this a proper customization point or remove the option to override it.
379# ifndef _LIBCPP_OVERRIDABLE_FUNC_VIS
380# define _LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_VISIBILITY("default")
381# endif
382
383# if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS) && __has_attribute(__type_visibility__)
384# define _LIBCPP_NAMESPACE_VISIBILITY __attribute__((__type_visibility__("default")))
385# elif !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
386# define _LIBCPP_NAMESPACE_VISIBILITY __attribute__((__visibility__("default")))
387# else
388# define _LIBCPP_NAMESPACE_VISIBILITY
389# endif
390
391# endif // defined(_LIBCPP_OBJECT_FORMAT_COFF)
392
393# if __has_attribute(exclude_from_explicit_instantiation)
394# define _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION __attribute__((__exclude_from_explicit_instantiation__))
395# else
396// Try to approximate the effect of exclude_from_explicit_instantiation
397// (which is that entities are not assumed to be provided by explicit
398// template instantiations in the dylib) by always inlining those entities.
399# define _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION _LIBCPP_ALWAYS_INLINE
400# endif
401
402# ifdef _LIBCPP_COMPILER_CLANG_BASED
403# define _LIBCPP_DIAGNOSTIC_PUSH _Pragma("clang diagnostic push")
404# define _LIBCPP_DIAGNOSTIC_POP _Pragma("clang diagnostic pop")
405# define _LIBCPP_CLANG_DIAGNOSTIC_IGNORED(str) _Pragma(_LIBCPP_TOSTRING(clang diagnostic ignored str))
406# define _LIBCPP_GCC_DIAGNOSTIC_IGNORED(str)
407# elif defined(_LIBCPP_COMPILER_GCC)
408# define _LIBCPP_DIAGNOSTIC_PUSH _Pragma("GCC diagnostic push")
409# define _LIBCPP_DIAGNOSTIC_POP _Pragma("GCC diagnostic pop")
410# define _LIBCPP_CLANG_DIAGNOSTIC_IGNORED(str)
411# define _LIBCPP_GCC_DIAGNOSTIC_IGNORED(str) _Pragma(_LIBCPP_TOSTRING(GCC diagnostic ignored str))
412# else
413# define _LIBCPP_DIAGNOSTIC_PUSH
414# define _LIBCPP_DIAGNOSTIC_POP
415# define _LIBCPP_CLANG_DIAGNOSTIC_IGNORED(str)
416# define _LIBCPP_GCC_DIAGNOSTIC_IGNORED(str)
417# endif
418
419# if _LIBCPP_HARDENING_MODE == _LIBCPP_HARDENING_MODE_FAST
420# define _LIBCPP_HARDENING_SIG f
421# elif _LIBCPP_HARDENING_MODE == _LIBCPP_HARDENING_MODE_EXTENSIVE
422# define _LIBCPP_HARDENING_SIG s
423# elif _LIBCPP_HARDENING_MODE == _LIBCPP_HARDENING_MODE_DEBUG
424# define _LIBCPP_HARDENING_SIG d
425# else
426# define _LIBCPP_HARDENING_SIG n // "none"
427# endif
428
429# if !_LIBCPP_HAS_EXCEPTIONS
430# define _LIBCPP_EXCEPTIONS_SIG n
431# else
432# define _LIBCPP_EXCEPTIONS_SIG e
433# endif
434
435# define _LIBCPP_ODR_SIGNATURE \
436 _LIBCPP_CONCAT(_LIBCPP_CONCAT(_LIBCPP_HARDENING_SIG, _LIBCPP_EXCEPTIONS_SIG), _LIBCPP_VERSION)
437
438// This macro marks a symbol as being hidden from libc++'s ABI. This is achieved
439// on two levels:
440// 1. The symbol is given hidden visibility, which ensures that users won't start exporting
441// symbols from their dynamic library by means of using the libc++ headers. This ensures
442// that those symbols stay private to the dynamic library in which it is defined.
443//
444// 2. The symbol is given an ABI tag that encodes the ODR-relevant properties of the library.
445// This ensures that no ODR violation can arise from mixing two TUs compiled with different
446// versions or configurations of libc++ (such as exceptions vs no-exceptions). Indeed, if the
447// program contains two definitions of a function, the ODR requires them to be token-by-token
448// equivalent, and the linker is allowed to pick either definition and discard the other one.
449//
450// For example, if a program contains a copy of `vector::at()` compiled with exceptions enabled
451// *and* a copy of `vector::at()` compiled with exceptions disabled (by means of having two TUs
452// compiled with different settings), the two definitions are both visible by the linker and they
453// have the same name, but they have a meaningfully different implementation (one throws an exception
454// and the other aborts the program). This violates the ODR and makes the program ill-formed, and in
455// practice what will happen is that the linker will pick one of the definitions at random and will
456// discard the other one. This can quite clearly lead to incorrect program behavior.
457//
458// A similar reasoning holds for many other properties that are ODR-affecting. Essentially any
459// property that causes the code of a function to differ from the code in another configuration
460// can be considered ODR-affecting. In practice, we don't encode all such properties in the ABI
461// tag, but we encode the ones that we think are most important: library version, exceptions, and
462// hardening mode.
463//
464// Note that historically, solving this problem has been achieved in various ways, including
465// force-inlining all functions or giving internal linkage to all functions. Both these previous
466// solutions suffer from drawbacks that lead notably to code bloat.
467//
468// Note that we use _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION to ensure that we don't depend
469// on _LIBCPP_HIDE_FROM_ABI methods of classes explicitly instantiated in the dynamic library.
470//
471// Also note that the _LIBCPP_HIDE_FROM_ABI_VIRTUAL macro should be used on virtual functions
472// instead of _LIBCPP_HIDE_FROM_ABI. That macro does not use an ABI tag. Indeed, the mangled
473// name of a virtual function is part of its ABI, since some architectures like arm64e can sign
474// the virtual function pointer in the vtable based on the mangled name of the function. Since
475// we use an ABI tag that changes with each released version, the mangled name of the virtual
476// function would change, which is incorrect. Note that it doesn't make much sense to change
477// the implementation of a virtual function in an ABI-incompatible way in the first place,
478// since that would be an ABI break anyway. Hence, the lack of ABI tag should not be noticeable.
479//
480// The macro can be applied to record and enum types. When the tagged type is nested in
481// a record this "parent" record needs to have the macro too. Another use case for applying
482// this macro to records and unions is to apply an ABI tag to inline constexpr variables.
483// This can be useful for inline variables that are implementation details which are expected
484// to change in the future.
485//
486// TODO: We provide a escape hatch with _LIBCPP_NO_ABI_TAG for folks who want to avoid increasing
487// the length of symbols with an ABI tag. In practice, we should remove the escape hatch and
488// use compression mangling instead, see https://github.com/itanium-cxx-abi/cxx-abi/issues/70.
489# ifndef _LIBCPP_NO_ABI_TAG
490# define _LIBCPP_HIDE_FROM_ABI \
491 _LIBCPP_HIDDEN _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION \
492 __attribute__((__abi_tag__(_LIBCPP_TOSTRING(_LIBCPP_ODR_SIGNATURE))))
493# else
494# define _LIBCPP_HIDE_FROM_ABI _LIBCPP_HIDDEN _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION
495# endif
496# define _LIBCPP_HIDE_FROM_ABI_VIRTUAL _LIBCPP_HIDDEN _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION
497
498# ifdef _LIBCPP_BUILDING_LIBRARY
499# if _LIBCPP_ABI_VERSION > 1
500# define _LIBCPP_HIDE_FROM_ABI_AFTER_V1 _LIBCPP_HIDE_FROM_ABI
501# else
502# define _LIBCPP_HIDE_FROM_ABI_AFTER_V1
503# endif
504# else
505# define _LIBCPP_HIDE_FROM_ABI_AFTER_V1 _LIBCPP_HIDE_FROM_ABI
506# endif
507
508// Clang modules take a significant compile time hit when pushing and popping diagnostics.
509// Since all the headers are marked as system headers unless _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER is defined, we can
510// simply disable this pushing and popping when _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER isn't defined.
511# ifdef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
512# define _LIBCPP_PUSH_EXTENSION_DIAGNOSTICS \
513 _LIBCPP_DIAGNOSTIC_PUSH \
514 _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wc++11-extensions") \
515 _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wc++14-extensions") \
516 _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wc++17-extensions") \
517 _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wc++20-extensions") \
518 _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wc++23-extensions") \
519 _LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Wc++14-extensions") \
520 _LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Wc++17-extensions") \
521 _LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Wc++20-extensions") \
522 _LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Wc++23-extensions")
523# define _LIBCPP_POP_EXTENSION_DIAGNOSTICS _LIBCPP_DIAGNOSTIC_POP
524# else
525# define _LIBCPP_PUSH_EXTENSION_DIAGNOSTICS
526# define _LIBCPP_POP_EXTENSION_DIAGNOSTICS
527# endif
528
529// clang-format off
530
531// The unversioned namespace is used when we want to be ABI compatible with other standard libraries in some way. There
532// are two main categories where that's the case:
533// - Historically, we have made exception types ABI compatible with libstdc++ to allow throwing them between libstdc++
534// and libc++. This is not used anymore for new exception types, since there is no use-case for it anymore.
535// - Types and functions which are used by the compiler are in the unversioned namespace, since the compiler has to know
536// their mangling without the appropriate declaration in some cases.
537// If it's not clear whether using the unversioned namespace is the correct thing to do, it's not. The versioned
538// namespace (_LIBCPP_BEGIN_NAMESPACE_STD) should almost always be used.
539# define _LIBCPP_BEGIN_UNVERSIONED_NAMESPACE_STD \
540 _LIBCPP_PUSH_EXTENSION_DIAGNOSTICS namespace _LIBCPP_NAMESPACE_VISIBILITY std {
541
542# define _LIBCPP_END_UNVERSIONED_NAMESPACE_STD } _LIBCPP_POP_EXTENSION_DIAGNOSTICS
543
544# define _LIBCPP_BEGIN_NAMESPACE_STD _LIBCPP_BEGIN_UNVERSIONED_NAMESPACE_STD inline namespace _LIBCPP_ABI_NAMESPACE {
545# define _LIBCPP_END_NAMESPACE_STD } _LIBCPP_END_UNVERSIONED_NAMESPACE_STD
546
547// TODO: This should really be in the versioned namespace
548#define _LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL _LIBCPP_BEGIN_UNVERSIONED_NAMESPACE_STD namespace experimental {
549#define _LIBCPP_END_NAMESPACE_EXPERIMENTAL } _LIBCPP_END_UNVERSIONED_NAMESPACE_STD
550
551#define _LIBCPP_BEGIN_NAMESPACE_LFTS _LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL inline namespace fundamentals_v1 {
552#define _LIBCPP_END_NAMESPACE_LFTS } _LIBCPP_END_NAMESPACE_EXPERIMENTAL
553
554#define _LIBCPP_BEGIN_NAMESPACE_LFTS_V2 _LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL inline namespace fundamentals_v2 {
555#define _LIBCPP_END_NAMESPACE_LFTS_V2 } _LIBCPP_END_NAMESPACE_EXPERIMENTAL
556
557#ifdef _LIBCPP_ABI_NO_FILESYSTEM_INLINE_NAMESPACE
558# define _LIBCPP_BEGIN_NAMESPACE_FILESYSTEM _LIBCPP_BEGIN_NAMESPACE_STD namespace filesystem {
559# define _LIBCPP_END_NAMESPACE_FILESYSTEM } _LIBCPP_END_NAMESPACE_STD
560#else
561# define _LIBCPP_BEGIN_NAMESPACE_FILESYSTEM _LIBCPP_BEGIN_NAMESPACE_STD \
562 inline namespace __fs { namespace filesystem {
563
564# define _LIBCPP_END_NAMESPACE_FILESYSTEM }} _LIBCPP_END_NAMESPACE_STD
565#endif
566
567// clang-format on
568
569# if __has_attribute(__enable_if__)
570# define _LIBCPP_PREFERRED_OVERLOAD __attribute__((__enable_if__(true, "")))
571# endif
572
573# if !defined(__SIZEOF_INT128__) || defined(_MSC_VER)
574# define _LIBCPP_HAS_INT128 0
575# else
576# define _LIBCPP_HAS_INT128 1
577# endif
578
579# ifdef _LIBCPP_CXX03_LANG
580# define _LIBCPP_DECLARE_STRONG_ENUM(x) \
581 struct _LIBCPP_EXPORTED_FROM_ABI x { \
582 enum __lx
583// clang-format off
584# define _LIBCPP_DECLARE_STRONG_ENUM_EPILOG(x) \
585 __lx __v_; \
586 _LIBCPP_HIDE_FROM_ABI x(__lx __v) : __v_(__v) {} \
587 _LIBCPP_HIDE_FROM_ABI explicit x(int __v) : __v_(static_cast<__lx>(__v)) {} \
588 _LIBCPP_HIDE_FROM_ABI operator int() const { return __v_; } \
589 };
590// clang-format on
591
592# else // _LIBCPP_CXX03_LANG
593# define _LIBCPP_DECLARE_STRONG_ENUM(x) enum class x
594# define _LIBCPP_DECLARE_STRONG_ENUM_EPILOG(x)
595# endif // _LIBCPP_CXX03_LANG
596
597# ifdef __FreeBSD__
598# define _DECLARE_C99_LDBL_MATH 1
599# endif
600
601// If we are getting operator new from the MSVC CRT, then allocation overloads
602// for align_val_t were added in 19.12, aka VS 2017 version 15.3.
603# if defined(_LIBCPP_MSVCRT) && defined(_MSC_VER) && _MSC_VER < 1912
604# define _LIBCPP_HAS_LIBRARY_ALIGNED_ALLOCATION 0
605# elif defined(_LIBCPP_ABI_VCRUNTIME) && !defined(__cpp_aligned_new)
606// We're deferring to Microsoft's STL to provide aligned new et al. We don't
607// have it unless the language feature test macro is defined.
608# define _LIBCPP_HAS_LIBRARY_ALIGNED_ALLOCATION 0
609# elif defined(__MVS__)
610# define _LIBCPP_HAS_LIBRARY_ALIGNED_ALLOCATION 0
611# else
612# define _LIBCPP_HAS_LIBRARY_ALIGNED_ALLOCATION 1
613# endif
614
615# if !_LIBCPP_HAS_LIBRARY_ALIGNED_ALLOCATION || (!defined(__cpp_aligned_new) || __cpp_aligned_new < 201606)
616# define _LIBCPP_HAS_ALIGNED_ALLOCATION 0
617# else
618# define _LIBCPP_HAS_ALIGNED_ALLOCATION 1
619# endif
620
621// It is not yet possible to use aligned_alloc() on all Apple platforms since
622// 10.15 was the first version to ship an implementation of aligned_alloc().
623# if defined(__APPLE__)
624# if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && \
625 __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101500) || \
626 (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && \
627 __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 130000) || \
628 (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && \
629 __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 60000) || \
630 (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 130000)
631# define _LIBCPP_HAS_C11_ALIGNED_ALLOC 0
632# else
633# define _LIBCPP_HAS_C11_ALIGNED_ALLOC 1
634# endif
635# elif defined(__ANDROID__) && __ANDROID_API__ < 28
636// Android only provides aligned_alloc when targeting API 28 or higher.
637# define _LIBCPP_HAS_C11_ALIGNED_ALLOC 0
638# else
639# define _LIBCPP_HAS_C11_ALIGNED_ALLOC 1
640# endif
641
642# if defined(__APPLE__) || defined(__FreeBSD__)
643# define _LIBCPP_HAS_DEFAULTRUNELOCALE
644# endif
645
646# if defined(__APPLE__) || defined(__FreeBSD__)
647# define _LIBCPP_WCTYPE_IS_MASK
648# endif
649
650# if _LIBCPP_STD_VER <= 17 || !defined(__cpp_char8_t)
651# define _LIBCPP_HAS_CHAR8_T 0
652# else
653# define _LIBCPP_HAS_CHAR8_T 1
654# endif
655
656// Deprecation macros.
657//
658// Deprecations warnings are always enabled, except when users explicitly opt-out
659// by defining _LIBCPP_DISABLE_DEPRECATION_WARNINGS.
660# if !defined(_LIBCPP_DISABLE_DEPRECATION_WARNINGS)
661# if __has_attribute(__deprecated__)
662# define _LIBCPP_DEPRECATED __attribute__((__deprecated__))
663# define _LIBCPP_DEPRECATED_(m) __attribute__((__deprecated__(m)))
664# elif _LIBCPP_STD_VER >= 14
665# define _LIBCPP_DEPRECATED [[deprecated]]
666# define _LIBCPP_DEPRECATED_(m) [[deprecated(m)]]
667# else
668# define _LIBCPP_DEPRECATED
669# define _LIBCPP_DEPRECATED_(m)
670# endif
671# else
672# define _LIBCPP_DEPRECATED
673# define _LIBCPP_DEPRECATED_(m)
674# endif
675
676# if !defined(_LIBCPP_CXX03_LANG)
677# define _LIBCPP_DEPRECATED_IN_CXX11 _LIBCPP_DEPRECATED
678# else
679# define _LIBCPP_DEPRECATED_IN_CXX11
680# endif
681
682# if _LIBCPP_STD_VER >= 14
683# define _LIBCPP_DEPRECATED_IN_CXX14 _LIBCPP_DEPRECATED
684# else
685# define _LIBCPP_DEPRECATED_IN_CXX14
686# endif
687
688# if _LIBCPP_STD_VER >= 17
689# define _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_DEPRECATED
690# else
691# define _LIBCPP_DEPRECATED_IN_CXX17
692# endif
693
694# if _LIBCPP_STD_VER >= 20
695# define _LIBCPP_DEPRECATED_IN_CXX20 _LIBCPP_DEPRECATED
696# else
697# define _LIBCPP_DEPRECATED_IN_CXX20
698# endif
699
700# if _LIBCPP_STD_VER >= 23
701# define _LIBCPP_DEPRECATED_IN_CXX23 _LIBCPP_DEPRECATED
702# else
703# define _LIBCPP_DEPRECATED_IN_CXX23
704# endif
705
706# if _LIBCPP_STD_VER >= 26
707# define _LIBCPP_DEPRECATED_IN_CXX26 _LIBCPP_DEPRECATED
708# define _LIBCPP_DEPRECATED_IN_CXX26_(m) _LIBCPP_DEPRECATED_(m)
709# else
710# define _LIBCPP_DEPRECATED_IN_CXX26
711# define _LIBCPP_DEPRECATED_IN_CXX26_(m)
712# endif
713
714# if _LIBCPP_HAS_CHAR8_T
715# define _LIBCPP_DEPRECATED_WITH_CHAR8_T _LIBCPP_DEPRECATED
716# else
717# define _LIBCPP_DEPRECATED_WITH_CHAR8_T
718# endif
719
720// Macros to enter and leave a state where deprecation warnings are suppressed.
721# if defined(_LIBCPP_COMPILER_CLANG_BASED) || defined(_LIBCPP_COMPILER_GCC)
722# define _LIBCPP_SUPPRESS_DEPRECATED_PUSH \
723 _Pragma("GCC diagnostic push") _Pragma("GCC diagnostic ignored \"-Wdeprecated\"") \
724 _Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"")
725# define _LIBCPP_SUPPRESS_DEPRECATED_POP _Pragma("GCC diagnostic pop")
726# else
727# define _LIBCPP_SUPPRESS_DEPRECATED_PUSH
728# define _LIBCPP_SUPPRESS_DEPRECATED_POP
729# endif
730
731# if _LIBCPP_STD_VER <= 11
732# define _LIBCPP_EXPLICIT_SINCE_CXX14
733# else
734# define _LIBCPP_EXPLICIT_SINCE_CXX14 explicit
735# endif
736
737# if _LIBCPP_STD_VER >= 23
738# define _LIBCPP_EXPLICIT_SINCE_CXX23 explicit
739# else
740# define _LIBCPP_EXPLICIT_SINCE_CXX23
741# endif
742
743# if _LIBCPP_STD_VER >= 14
744# define _LIBCPP_CONSTEXPR_SINCE_CXX14 constexpr
745# else
746# define _LIBCPP_CONSTEXPR_SINCE_CXX14
747# endif
748
749# if _LIBCPP_STD_VER >= 17
750# define _LIBCPP_CONSTEXPR_SINCE_CXX17 constexpr
751# else
752# define _LIBCPP_CONSTEXPR_SINCE_CXX17
753# endif
754
755# if _LIBCPP_STD_VER >= 20
756# define _LIBCPP_CONSTEXPR_SINCE_CXX20 constexpr
757# else
758# define _LIBCPP_CONSTEXPR_SINCE_CXX20
759# endif
760
761# if _LIBCPP_STD_VER >= 23
762# define _LIBCPP_CONSTEXPR_SINCE_CXX23 constexpr
763# else
764# define _LIBCPP_CONSTEXPR_SINCE_CXX23
765# endif
766
767# if _LIBCPP_STD_VER >= 26
768# define _LIBCPP_CONSTEXPR_SINCE_CXX26 constexpr
769# else
770# define _LIBCPP_CONSTEXPR_SINCE_CXX26
771# endif
772
773# ifndef _LIBCPP_WEAK
774# define _LIBCPP_WEAK __attribute__((__weak__))
775# endif
776
777// Thread API
778// clang-format off
779# if _LIBCPP_HAS_THREADS && \
780 !_LIBCPP_HAS_THREAD_API_PTHREAD && \
781 !_LIBCPP_HAS_THREAD_API_WIN32 && \
782 !_LIBCPP_HAS_THREAD_API_EXTERNAL
783
784# if defined(__FreeBSD__) || \
785 defined(__wasi__) || \
786 defined(__NetBSD__) || \
787 defined(__OpenBSD__) || \
788 defined(__NuttX__) || \
789 defined(__linux__) || \
790 defined(__GNU__) || \
791 defined(__APPLE__) || \
792 defined(__MVS__) || \
793 defined(_AIX) || \
794 defined(__EMSCRIPTEN__)
795// clang-format on
796# undef _LIBCPP_HAS_THREAD_API_PTHREAD
797# define _LIBCPP_HAS_THREAD_API_PTHREAD 1
798# elif defined(__Fuchsia__)
799// TODO(44575): Switch to C11 thread API when possible.
800# undef _LIBCPP_HAS_THREAD_API_PTHREAD
801# define _LIBCPP_HAS_THREAD_API_PTHREAD 1
802# elif defined(_LIBCPP_WIN32API)
803# undef _LIBCPP_HAS_THREAD_API_WIN32
804# define _LIBCPP_HAS_THREAD_API_WIN32 1
805# else
806# error "No thread API"
807# endif // _LIBCPP_HAS_THREAD_API
808# endif // _LIBCPP_HAS_THREADS
809
810# if _LIBCPP_HAS_THREAD_API_PTHREAD
811# if defined(__ANDROID__) && __ANDROID_API__ >= 30
812# define _LIBCPP_HAS_COND_CLOCKWAIT 1
813# elif defined(_LIBCPP_GLIBC_PREREQ)
814# if _LIBCPP_GLIBC_PREREQ(2, 30)
815# define _LIBCPP_HAS_COND_CLOCKWAIT 1
816# else
817# define _LIBCPP_HAS_COND_CLOCKWAIT 0
818# endif
819# else
820# define _LIBCPP_HAS_COND_CLOCKWAIT 0
821# endif
822# else
823# define _LIBCPP_HAS_COND_CLOCKWAIT 0
824# endif
825
826# if !_LIBCPP_HAS_THREADS && _LIBCPP_HAS_THREAD_API_PTHREAD
827# error _LIBCPP_HAS_THREAD_API_PTHREAD may only be true when _LIBCPP_HAS_THREADS is true.
828# endif
829
830# if !_LIBCPP_HAS_THREADS && _LIBCPP_HAS_THREAD_API_EXTERNAL
831# error _LIBCPP_HAS_THREAD_API_EXTERNAL may only be true when _LIBCPP_HAS_THREADS is true.
832# endif
833
834# if !_LIBCPP_HAS_MONOTONIC_CLOCK && _LIBCPP_HAS_THREADS
835# error _LIBCPP_HAS_MONOTONIC_CLOCK may only be false when _LIBCPP_HAS_THREADS is false.
836# endif
837
838# if _LIBCPP_HAS_THREADS && !defined(__STDCPP_THREADS__)
839# define __STDCPP_THREADS__ 1
840# endif
841
842// The glibc and Bionic implementation of pthreads implements
843// pthread_mutex_destroy as nop for regular mutexes. Additionally, Win32
844// mutexes have no destroy mechanism.
845//
846// This optimization can't be performed on Apple platforms, where
847// pthread_mutex_destroy can allow the kernel to release resources.
848// See https://llvm.org/D64298 for details.
849//
850// TODO(EricWF): Enable this optimization on Bionic after speaking to their
851// respective stakeholders.
852// clang-format off
853# if (_LIBCPP_HAS_THREAD_API_PTHREAD && defined(__GLIBC__)) || \
854 (_LIBCPP_HAS_THREAD_API_C11 && defined(__Fuchsia__)) || \
855 _LIBCPP_HAS_THREAD_API_WIN32
856// clang-format on
857# define _LIBCPP_HAS_TRIVIAL_MUTEX_DESTRUCTION 1
858# else
859# define _LIBCPP_HAS_TRIVIAL_MUTEX_DESTRUCTION 0
860# endif
861
862// Destroying a condvar is a nop on Windows.
863//
864// This optimization can't be performed on Apple platforms, where
865// pthread_cond_destroy can allow the kernel to release resources.
866// See https://llvm.org/D64298 for details.
867//
868// TODO(EricWF): This is potentially true for some pthread implementations
869// as well.
870# if (_LIBCPP_HAS_THREAD_API_C11 && defined(__Fuchsia__)) || _LIBCPP_HAS_THREAD_API_WIN32
871# define _LIBCPP_HAS_TRIVIAL_CONDVAR_DESTRUCTION 1
872# else
873# define _LIBCPP_HAS_TRIVIAL_CONDVAR_DESTRUCTION 0
874# endif
875
876# if defined(__BIONIC__) || defined(__NuttX__) || defined(__Fuchsia__) || defined(__wasi__) || \
877 _LIBCPP_HAS_MUSL_LIBC || defined(__OpenBSD__) || defined(__LLVM_LIBC__)
878# define _LIBCPP_PROVIDES_DEFAULT_RUNE_TABLE
879# endif
880
881# if __has_feature(cxx_atomic) || __has_extension(c_atomic) || __has_keyword(_Atomic)
882# define _LIBCPP_HAS_C_ATOMIC_IMP 1
883# define _LIBCPP_HAS_GCC_ATOMIC_IMP 0
884# define _LIBCPP_HAS_EXTERNAL_ATOMIC_IMP 0
885# elif defined(_LIBCPP_COMPILER_GCC)
886# define _LIBCPP_HAS_C_ATOMIC_IMP 0
887# define _LIBCPP_HAS_GCC_ATOMIC_IMP 1
888# define _LIBCPP_HAS_EXTERNAL_ATOMIC_IMP 0
889# endif
890
891# if !_LIBCPP_HAS_C_ATOMIC_IMP && !_LIBCPP_HAS_GCC_ATOMIC_IMP && !_LIBCPP_HAS_EXTERNAL_ATOMIC_IMP
892# define _LIBCPP_HAS_ATOMIC_HEADER 0
893# else
894# define _LIBCPP_HAS_ATOMIC_HEADER 1
895# ifndef _LIBCPP_ATOMIC_FLAG_TYPE
896# define _LIBCPP_ATOMIC_FLAG_TYPE bool
897# endif
898# endif
899
900# if defined(__FreeBSD__) && defined(__clang__) && __has_attribute(__no_thread_safety_analysis__)
901# define _LIBCPP_NO_THREAD_SAFETY_ANALYSIS __attribute__((__no_thread_safety_analysis__))
902# else
903# define _LIBCPP_NO_THREAD_SAFETY_ANALYSIS
904# endif
905
906// Work around the attribute handling in clang. When both __declspec and
907// __attribute__ are present, the processing goes awry preventing the definition
908// of the types. In MinGW mode, __declspec evaluates to __attribute__, and thus
909// combining the two does work.
910# if defined(_LIBCPP_ENABLE_THREAD_SAFETY_ANNOTATIONS) && defined(__clang__) && \
911 __has_attribute(acquire_capability) && !defined(_MSC_VER)
912# define _LIBCPP_HAS_THREAD_SAFETY_ANNOTATIONS 1
913# else
914# define _LIBCPP_HAS_THREAD_SAFETY_ANNOTATIONS 0
915# endif
916
917# if _LIBCPP_HAS_THREAD_SAFETY_ANNOTATIONS
918# define _LIBCPP_THREAD_SAFETY_ANNOTATION(x) __attribute__((x))
919# else
920# define _LIBCPP_THREAD_SAFETY_ANNOTATION(x)
921# endif
922
923# if _LIBCPP_STD_VER >= 20
924# define _LIBCPP_CONSTINIT constinit
925# elif __has_attribute(__require_constant_initialization__)
926# define _LIBCPP_CONSTINIT __attribute__((__require_constant_initialization__))
927# else
928# define _LIBCPP_CONSTINIT
929# endif
930
931# if defined(__CUDACC__) || defined(__CUDA_ARCH__) || defined(__CUDA_LIBDEVICE__)
932// The CUDA SDK contains an unfortunate definition for the __noinline__ macro,
933// which breaks the regular __attribute__((__noinline__)) syntax. Therefore,
934// when compiling for CUDA we use the non-underscored version of the noinline
935// attribute.
936//
937// This is a temporary workaround and we still expect the CUDA SDK team to solve
938// this issue properly in the SDK headers.
939//
940// See https://github.com/llvm/llvm-project/pull/73838 for more details.
941# define _LIBCPP_NOINLINE __attribute__((noinline))
942# elif __has_attribute(__noinline__)
943# define _LIBCPP_NOINLINE __attribute__((__noinline__))
944# else
945# define _LIBCPP_NOINLINE
946# endif
947
948// We often repeat things just for handling wide characters in the library.
949// When wide characters are disabled, it can be useful to have a quick way of
950// disabling it without having to resort to #if-#endif, which has a larger
951// impact on readability.
952# if !_LIBCPP_HAS_WIDE_CHARACTERS
953# define _LIBCPP_IF_WIDE_CHARACTERS(...)
954# else
955# define _LIBCPP_IF_WIDE_CHARACTERS(...) __VA_ARGS__
956# endif
957
958// clang-format off
959# define _LIBCPP_PUSH_MACROS _Pragma("push_macro(\"min\")") _Pragma("push_macro(\"max\")") _Pragma("push_macro(\"refresh\")") _Pragma("push_macro(\"move\")") _Pragma("push_macro(\"erase\")")
960# define _LIBCPP_POP_MACROS _Pragma("pop_macro(\"min\")") _Pragma("pop_macro(\"max\")") _Pragma("pop_macro(\"refresh\")") _Pragma("pop_macro(\"move\")") _Pragma("pop_macro(\"erase\")")
961// clang-format on
962
963# ifndef _LIBCPP_NO_AUTO_LINK
964# if defined(_LIBCPP_ABI_MICROSOFT) && !defined(_LIBCPP_BUILDING_LIBRARY)
965# if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
966# pragma comment(lib, "c++.lib")
967# else
968# pragma comment(lib, "libc++.lib")
969# endif
970# endif // defined(_LIBCPP_ABI_MICROSOFT) && !defined(_LIBCPP_BUILDING_LIBRARY)
971# endif // _LIBCPP_NO_AUTO_LINK
972
973// Configures the fopen close-on-exec mode character, if any. This string will
974// be appended to any mode string used by fstream for fopen/fdopen.
975//
976// Not all platforms support this, but it helps avoid fd-leaks on platforms that
977// do.
978# if defined(__BIONIC__)
979# define _LIBCPP_FOPEN_CLOEXEC_MODE "e"
980# else
981# define _LIBCPP_FOPEN_CLOEXEC_MODE
982# endif
983
984# if __has_cpp_attribute(msvc::no_unique_address)
985// MSVC implements [[no_unique_address]] as a silent no-op currently.
986// (If/when MSVC breaks its C++ ABI, it will be changed to work as intended.)
987// However, MSVC implements [[msvc::no_unique_address]] which does what
988// [[no_unique_address]] is supposed to do, in general.
989# define _LIBCPP_NO_UNIQUE_ADDRESS [[msvc::no_unique_address]]
990# else
991# define _LIBCPP_NO_UNIQUE_ADDRESS [[__no_unique_address__]]
992# endif
993
994// c8rtomb() and mbrtoc8() were added in C++20 and C23. Support for these
995// functions is gradually being added to existing C libraries. The conditions
996// below check for known C library versions and conditions under which these
997// functions are declared by the C library.
998//
999// GNU libc 2.36 and newer declare c8rtomb() and mbrtoc8() in C++ modes if
1000// __cpp_char8_t is defined or if C2X extensions are enabled. Determining
1001// the latter depends on internal GNU libc details that are not appropriate
1002// to depend on here, so any declarations present when __cpp_char8_t is not
1003// defined are ignored.
1004# if defined(_LIBCPP_GLIBC_PREREQ)
1005# if _LIBCPP_GLIBC_PREREQ(2, 36) && defined(__cpp_char8_t)
1006# define _LIBCPP_HAS_C8RTOMB_MBRTOC8 1
1007# else
1008# define _LIBCPP_HAS_C8RTOMB_MBRTOC8 0
1009# endif
1010# else
1011# define _LIBCPP_HAS_C8RTOMB_MBRTOC8 0
1012# endif
1013
1014// There are a handful of public standard library types that are intended to
1015// support CTAD but don't need any explicit deduction guides to do so. This
1016// macro is used to mark them as such, which suppresses the
1017// '-Wctad-maybe-unsupported' compiler warning when CTAD is used in user code
1018// with these classes.
1019# if _LIBCPP_STD_VER >= 17
1020# ifdef _LIBCPP_COMPILER_CLANG_BASED
1021# define _LIBCPP_CTAD_SUPPORTED_FOR_TYPE(_ClassName) \
1022 template <class... _Tag> \
1023 [[maybe_unused]] _ClassName(typename _Tag::__allow_ctad...)->_ClassName<_Tag...>
1024# else
1025# define _LIBCPP_CTAD_SUPPORTED_FOR_TYPE(ClassName) \
1026 template <class... _Tag> \
1027 ClassName(typename _Tag::__allow_ctad...)->ClassName<_Tag...>
1028# endif
1029# else
1030# define _LIBCPP_CTAD_SUPPORTED_FOR_TYPE(_ClassName) static_assert(true, "")
1031# endif
1032
1033// TODO(LLVM 22): Remove the workaround
1034# if defined(__OBJC__) && (!defined(_LIBCPP_CLANG_VER) || _LIBCPP_CLANG_VER < 2001)
1035# define _LIBCPP_WORKAROUND_OBJCXX_COMPILER_INTRINSICS
1036# endif
1037
1038# define _PSTL_PRAGMA(x) _Pragma(#x)
1039
1040// Enable SIMD for compilers that support OpenMP 4.0
1041# if (defined(_OPENMP) && _OPENMP >= 201307)
1042
1043# define _PSTL_UDR_PRESENT
1044# define _PSTL_PRAGMA_SIMD _PSTL_PRAGMA(omp simd)
1045# define _PSTL_PRAGMA_DECLARE_SIMD _PSTL_PRAGMA(omp declare simd)
1046# define _PSTL_PRAGMA_SIMD_REDUCTION(PRM) _PSTL_PRAGMA(omp simd reduction(PRM))
1047# define _PSTL_PRAGMA_SIMD_SCAN(PRM) _PSTL_PRAGMA(omp simd reduction(inscan, PRM))
1048# define _PSTL_PRAGMA_SIMD_INCLUSIVE_SCAN(PRM) _PSTL_PRAGMA(omp scan inclusive(PRM))
1049# define _PSTL_PRAGMA_SIMD_EXCLUSIVE_SCAN(PRM) _PSTL_PRAGMA(omp scan exclusive(PRM))
1050
1051// Declaration of reduction functor, where
1052// NAME - the name of the functor
1053// OP - type of the callable object with the reduction operation
1054// omp_in - refers to the local partial result
1055// omp_out - refers to the final value of the combiner operator
1056// omp_priv - refers to the private copy of the initial value
1057// omp_orig - refers to the original variable to be reduced
1058# define _PSTL_PRAGMA_DECLARE_REDUCTION(NAME, OP) \
1059 _PSTL_PRAGMA(omp declare reduction(NAME:OP : omp_out(omp_in)) initializer(omp_priv = omp_orig))
1060
1061# elif defined(_LIBCPP_COMPILER_CLANG_BASED)
1062
1063# define _PSTL_PRAGMA_SIMD _Pragma("clang loop vectorize(enable) interleave(enable)")
1064# define _PSTL_PRAGMA_DECLARE_SIMD
1065# define _PSTL_PRAGMA_SIMD_REDUCTION(PRM) _Pragma("clang loop vectorize(enable) interleave(enable)")
1066# define _PSTL_PRAGMA_SIMD_SCAN(PRM) _Pragma("clang loop vectorize(enable) interleave(enable)")
1067# define _PSTL_PRAGMA_SIMD_INCLUSIVE_SCAN(PRM)
1068# define _PSTL_PRAGMA_SIMD_EXCLUSIVE_SCAN(PRM)
1069# define _PSTL_PRAGMA_DECLARE_REDUCTION(NAME, OP)
1070
1071# else // (defined(_OPENMP) && _OPENMP >= 201307)
1072
1073# define _PSTL_PRAGMA_SIMD
1074# define _PSTL_PRAGMA_DECLARE_SIMD
1075# define _PSTL_PRAGMA_SIMD_REDUCTION(PRM)
1076# define _PSTL_PRAGMA_SIMD_SCAN(PRM)
1077# define _PSTL_PRAGMA_SIMD_INCLUSIVE_SCAN(PRM)
1078# define _PSTL_PRAGMA_SIMD_EXCLUSIVE_SCAN(PRM)
1079# define _PSTL_PRAGMA_DECLARE_REDUCTION(NAME, OP)
1080
1081# endif // (defined(_OPENMP) && _OPENMP >= 201307)
1082
1083# define _PSTL_USE_NONTEMPORAL_STORES_IF_ALLOWED
1084
1085// Optional attributes - these are useful for a better QoI, but not required to be available
1086
1087# define _LIBCPP_NOALIAS __attribute__((__malloc__))
1088# define _LIBCPP_NODEBUG [[__gnu__::__nodebug__]]
1089# define _LIBCPP_NO_SANITIZE(...) __attribute__((__no_sanitize__(__VA_ARGS__)))
1090# define _LIBCPP_INIT_PRIORITY_MAX __attribute__((__init_priority__(100)))
1091# define _LIBCPP_ATTRIBUTE_FORMAT(archetype, format_string_index, first_format_arg_index) \
1092 __attribute__((__format__(archetype, format_string_index, first_format_arg_index)))
1093# define _LIBCPP_PACKED __attribute__((__packed__))
1094
1095# if __has_attribute(__no_sanitize__) && !defined(_LIBCPP_COMPILER_GCC)
1096# define _LIBCPP_NO_CFI __attribute__((__no_sanitize__("cfi")))
1097# else
1098# define _LIBCPP_NO_CFI
1099# endif
1100
1101# if __has_attribute(__using_if_exists__)
1102# define _LIBCPP_USING_IF_EXISTS __attribute__((__using_if_exists__))
1103# else
1104# define _LIBCPP_USING_IF_EXISTS
1105# endif
1106
1107# if __has_cpp_attribute(_Clang::__no_destroy__)
1108# define _LIBCPP_NO_DESTROY [[_Clang::__no_destroy__]]
1109# else
1110# define _LIBCPP_NO_DESTROY
1111# endif
1112
1113# if __has_attribute(__diagnose_if__)
1114# define _LIBCPP_DIAGNOSE_WARNING(...) __attribute__((__diagnose_if__(__VA_ARGS__, "warning")))
1115# else
1116# define _LIBCPP_DIAGNOSE_WARNING(...)
1117# endif
1118
1119# if __has_cpp_attribute(_Clang::__lifetimebound__)
1120# define _LIBCPP_LIFETIMEBOUND [[_Clang::__lifetimebound__]]
1121# else
1122# define _LIBCPP_LIFETIMEBOUND
1123# endif
1124
1125# if __has_cpp_attribute(_Clang::__noescape__)
1126# define _LIBCPP_NOESCAPE [[_Clang::__noescape__]]
1127# else
1128# define _LIBCPP_NOESCAPE
1129# endif
1130
1131# if __has_cpp_attribute(_Clang::__no_specializations__)
1132# define _LIBCPP_NO_SPECIALIZATIONS \
1133 [[_Clang::__no_specializations__("Users are not allowed to specialize this standard library entity")]]
1134# else
1135# define _LIBCPP_NO_SPECIALIZATIONS
1136# endif
1137
1138# if __has_cpp_attribute(_Clang::__standalone_debug__)
1139# define _LIBCPP_STANDALONE_DEBUG [[_Clang::__standalone_debug__]]
1140# else
1141# define _LIBCPP_STANDALONE_DEBUG
1142# endif
1143
1144# if __has_cpp_attribute(_Clang::__preferred_name__)
1145# define _LIBCPP_PREFERRED_NAME(x) [[_Clang::__preferred_name__(x)]]
1146# else
1147# define _LIBCPP_PREFERRED_NAME(x)
1148# endif
1149
1150# if defined(_LIBCPP_ABI_MICROSOFT) && __has_declspec_attribute(empty_bases)
1151# define _LIBCPP_DECLSPEC_EMPTY_BASES __declspec(empty_bases)
1152# else
1153# define _LIBCPP_DECLSPEC_EMPTY_BASES
1154# endif
1155
1156// Allow for build-time disabling of unsigned integer sanitization
1157# if __has_attribute(no_sanitize) && !defined(_LIBCPP_COMPILER_GCC)
1158# define _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK __attribute__((__no_sanitize__("unsigned-integer-overflow")))
1159# else
1160# define _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
1161# endif
1162
1163# if __has_feature(nullability)
1164# define _LIBCPP_DIAGNOSE_NULLPTR _Nonnull
1165# else
1166# define _LIBCPP_DIAGNOSE_NULLPTR
1167# endif
1168
1169// TODO(LLVM 22): Remove this macro once LLVM19 support ends. __cpp_explicit_this_parameter has been set in LLVM20.
1170// Clang-18 has support for deducing this, but it does not set the FTM.
1171# if defined(__cpp_explicit_this_parameter) || (defined(_LIBCPP_CLANG_VER) && _LIBCPP_CLANG_VER >= 1800)
1172# define _LIBCPP_HAS_EXPLICIT_THIS_PARAMETER 1
1173# else
1174# define _LIBCPP_HAS_EXPLICIT_THIS_PARAMETER 0
1175# endif
1176
1177#endif // __cplusplus
1178
1179#endif // _LIBCPP___CONFIG
1180