| // -*- C++ -*- | |
| //===----------------------------------------------------------------------===// | |
| // | |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. | |
| // See https://llvm.org/LICENSE.txt for license information. | |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception | |
| // | |
| //===----------------------------------------------------------------------===// | |
| #ifndef _LIBCPP___AVAILABILITY | |
| #define _LIBCPP___AVAILABILITY | |
| #include <__config> | |
| #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) | |
| # pragma GCC system_header | |
| #endif | |
| // Libc++ is shipped by various vendors. In particular, it is used as a system | |
| // library on macOS, iOS and other Apple platforms. In order for users to be | |
| // able to compile a binary that is intended to be deployed to an older version | |
| // of a platform, Clang provides availability attributes [1]. These attributes | |
| // can be placed on declarations and are used to describe the life cycle of a | |
| // symbol in the library. | |
| // | |
| // The main goal is to ensure a compile-time error if a symbol that hasn't been | |
| // introduced in a previously released library is used in a program that targets | |
| // that previously released library. Normally, this would be a load-time error | |
| // when one tries to launch the program against the older library. | |
| // | |
| // For example, the filesystem library was introduced in the dylib in macOS 10.15. | |
| // If a user compiles on a macOS 10.15 host but targets macOS 10.13 with their | |
| // program, the compiler would normally not complain (because the required | |
| // declarations are in the headers), but the dynamic loader would fail to find | |
| // the symbols when actually trying to launch the program on macOS 10.13. To | |
| // turn this into a compile-time issue instead, declarations are annotated with | |
| // when they were introduced, and the compiler can produce a diagnostic if the | |
| // program references something that isn't available on the deployment target. | |
| // | |
| // This mechanism is general in nature, and any vendor can add their markup to | |
| // the library (see below). Whenever a new feature is added that requires support | |
| // in the shared library, a macro should be added below to mark this feature | |
| // as unavailable. When vendors decide to ship the feature as part of their | |
| // shared library, they can update the markup appropriately. | |
| // | |
| // Furthermore, many features in the standard library have corresponding | |
| // feature-test macros. When a feature is made unavailable on some deployment | |
| // target, a macro should be defined to signal that it is unavailable. That | |
| // macro can then be picked up when feature-test macros are generated (see | |
| // generate_feature_test_macro_components.py) to make sure that feature-test | |
| // macros don't announce a feature as being implemented if it has been marked | |
| // as unavailable. | |
| // | |
| // Note that this mechanism is disabled by default in the "upstream" libc++. | |
| // Availability annotations are only meaningful when shipping libc++ inside | |
| // a platform (i.e. as a system library), and so vendors that want them should | |
| // turn those annotations on at CMake configuration time. | |
| // | |
| // [1]: https://clang.llvm.org/docs/AttributeReference.html#availability | |
| // For backwards compatibility, allow users to define _LIBCPP_DISABLE_AVAILABILITY | |
| // for a while. | |
| #if defined(_LIBCPP_DISABLE_AVAILABILITY) | |
| # if !defined(_LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS) | |
| # define _LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS | |
| # endif | |
| #endif | |
| // Availability markup is disabled when building the library, or when the compiler | |
| // doesn't support the proper attributes. | |
| #if defined(_LIBCPP_BUILDING_LIBRARY) || \ | |
| defined(_LIBCXXABI_BUILDING_LIBRARY) || \ | |
| !__has_feature(attribute_availability_with_strict) || \ | |
| !__has_feature(attribute_availability_in_templates) || \ | |
| !__has_extension(pragma_clang_attribute_external_declaration) | |
| # if !defined(_LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS) | |
| # define _LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS | |
| # endif | |
| #endif | |
| #if defined(_LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS) | |
| // This controls the availability of std::shared_mutex and std::shared_timed_mutex, | |
| // which were added to the dylib later. | |
| # define _LIBCPP_AVAILABILITY_SHARED_MUTEX | |
| // # define _LIBCPP_AVAILABILITY_DISABLE_FTM___cpp_lib_shared_mutex | |
| // # define _LIBCPP_AVAILABILITY_DISABLE_FTM___cpp_lib_shared_timed_mutex | |
| // These macros control the availability of std::bad_optional_access and | |
| // other exception types. These were put in the shared library to prevent | |
| // code bloat from every user program defining the vtable for these exception | |
| // types. | |
| # define _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS | |
| # define _LIBCPP_AVAILABILITY_BAD_VARIANT_ACCESS | |
| # define _LIBCPP_AVAILABILITY_BAD_ANY_CAST | |
| // This controls the availability of std::uncaught_exceptions(). | |
| # define _LIBCPP_AVAILABILITY_UNCAUGHT_EXCEPTIONS | |
| // This controls the availability of the sized version of ::operator delete, | |
| // which was added to the dylib later. | |
| # define _LIBCPP_AVAILABILITY_SIZED_NEW_DELETE | |
| // This controls the availability of the std::future_error exception. | |
| # define _LIBCPP_AVAILABILITY_FUTURE_ERROR | |
| // This controls the availability of std::type_info's vtable. | |
| // I can't imagine how using std::type_info can work at all if | |
| // this isn't supported. | |
| # define _LIBCPP_AVAILABILITY_TYPEINFO_VTABLE | |
| // This controls the availability of std::locale::category members | |
| // (e.g. std::locale::collate), which are defined in the dylib. | |
| # define _LIBCPP_AVAILABILITY_LOCALE_CATEGORY | |
| // This controls the availability of atomic operations on std::shared_ptr | |
| // (e.g. `std::atomic_store(std::shared_ptr)`), which require a shared | |
| // lock table located in the dylib. | |
| # define _LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR | |
| // These macros control the availability of all parts of <filesystem> that | |
| // depend on something in the dylib. | |
| # define _LIBCPP_AVAILABILITY_FILESYSTEM | |
| # define _LIBCPP_AVAILABILITY_FILESYSTEM_PUSH | |
| # define _LIBCPP_AVAILABILITY_FILESYSTEM_POP | |
| // # define _LIBCPP_AVAILABILITY_DISABLE_FTM___cpp_lib_filesystem | |
| // This controls the availability of std::to_chars. | |
| # define _LIBCPP_AVAILABILITY_TO_CHARS | |
| // This controls the availability of the C++20 synchronization library, | |
| // which requires shared library support for various operations | |
| // (see libcxx/src/atomic.cpp). | |
| # define _LIBCPP_AVAILABILITY_SYNC | |
| // # define _LIBCPP_AVAILABILITY_DISABLE_FTM___cpp_lib_atomic_wait | |
| // # define _LIBCPP_AVAILABILITY_DISABLE_FTM___cpp_lib_barrier | |
| // # define _LIBCPP_AVAILABILITY_DISABLE_FTM___cpp_lib_latch | |
| // # define _LIBCPP_AVAILABILITY_DISABLE_FTM___cpp_lib_semaphore | |
| // This controls the availability of the C++20 format library. | |
| // The library is in development and not ABI stable yet. Currently | |
| // P2216 is aiming to be retroactively accepted in C++20. This paper | |
| // contains ABI breaking changes. | |
| # define _LIBCPP_AVAILABILITY_FORMAT | |
| // # define _LIBCPP_AVAILABILITY_DISABLE_FTM___cpp_lib_format | |
| #elif defined(__APPLE__) | |
| # define _LIBCPP_AVAILABILITY_SHARED_MUTEX \ | |
| __attribute__((availability(macosx,strict,introduced=10.12))) \ | |
| __attribute__((availability(ios,strict,introduced=10.0))) \ | |
| __attribute__((availability(tvos,strict,introduced=10.0))) \ | |
| __attribute__((availability(watchos,strict,introduced=3.0))) | |
| # if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101200) || \ | |
| (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 100000) || \ | |
| (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 100000) || \ | |
| (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 30000) | |
| # define _LIBCPP_AVAILABILITY_DISABLE_FTM___cpp_lib_shared_mutex | |
| # define _LIBCPP_AVAILABILITY_DISABLE_FTM___cpp_lib_shared_timed_mutex | |
| # endif | |
| # define _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS \ | |
| __attribute__((availability(macosx,strict,introduced=10.13))) \ | |
| __attribute__((availability(ios,strict,introduced=11.0))) \ | |
| __attribute__((availability(tvos,strict,introduced=11.0))) \ | |
| __attribute__((availability(watchos,strict,introduced=4.0))) | |
| # define _LIBCPP_AVAILABILITY_BAD_VARIANT_ACCESS \ | |
| _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS | |
| # define _LIBCPP_AVAILABILITY_BAD_ANY_CAST \ | |
| _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS | |
| # define _LIBCPP_AVAILABILITY_UNCAUGHT_EXCEPTIONS \ | |
| __attribute__((availability(macosx,strict,introduced=10.12))) \ | |
| __attribute__((availability(ios,strict,introduced=10.0))) \ | |
| __attribute__((availability(tvos,strict,introduced=10.0))) \ | |
| __attribute__((availability(watchos,strict,introduced=3.0))) | |
| # define _LIBCPP_AVAILABILITY_SIZED_NEW_DELETE \ | |
| __attribute__((availability(macosx,strict,introduced=10.12))) \ | |
| __attribute__((availability(ios,strict,introduced=10.0))) \ | |
| __attribute__((availability(tvos,strict,introduced=10.0))) \ | |
| __attribute__((availability(watchos,strict,introduced=3.0))) | |
| # define _LIBCPP_AVAILABILITY_FUTURE_ERROR \ | |
| __attribute__((availability(ios,strict,introduced=6.0))) | |
| # define _LIBCPP_AVAILABILITY_TYPEINFO_VTABLE \ | |
| __attribute__((availability(macosx,strict,introduced=10.9))) \ | |
| __attribute__((availability(ios,strict,introduced=7.0))) | |
| # define _LIBCPP_AVAILABILITY_LOCALE_CATEGORY \ | |
| __attribute__((availability(macosx,strict,introduced=10.9))) \ | |
| __attribute__((availability(ios,strict,introduced=7.0))) | |
| # define _LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR \ | |
| __attribute__((availability(macosx,strict,introduced=10.9))) \ | |
| __attribute__((availability(ios,strict,introduced=7.0))) | |
| # define _LIBCPP_AVAILABILITY_FILESYSTEM \ | |
| __attribute__((availability(macosx,strict,introduced=10.15))) \ | |
| __attribute__((availability(ios,strict,introduced=13.0))) \ | |
| __attribute__((availability(tvos,strict,introduced=13.0))) \ | |
| __attribute__((availability(watchos,strict,introduced=6.0))) | |
| # define _LIBCPP_AVAILABILITY_FILESYSTEM_PUSH \ | |
| _Pragma("clang attribute push(__attribute__((availability(macosx,strict,introduced=10.15))), apply_to=any(function,record))") \ | |
| _Pragma("clang attribute push(__attribute__((availability(ios,strict,introduced=13.0))), apply_to=any(function,record))") \ | |
| _Pragma("clang attribute push(__attribute__((availability(tvos,strict,introduced=13.0))), apply_to=any(function,record))") \ | |
| _Pragma("clang attribute push(__attribute__((availability(watchos,strict,introduced=6.0))), apply_to=any(function,record))") | |
| # define _LIBCPP_AVAILABILITY_FILESYSTEM_POP \ | |
| _Pragma("clang attribute pop") \ | |
| _Pragma("clang attribute pop") \ | |
| _Pragma("clang attribute pop") \ | |
| _Pragma("clang attribute pop") | |
| # if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101500) || \ | |
| (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 130000) || \ | |
| (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 130000) || \ | |
| (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 60000) | |
| # define _LIBCPP_AVAILABILITY_DISABLE_FTM___cpp_lib_filesystem | |
| # endif | |
| # define _LIBCPP_AVAILABILITY_TO_CHARS \ | |
| _LIBCPP_AVAILABILITY_FILESYSTEM | |
| # define _LIBCPP_AVAILABILITY_SYNC \ | |
| __attribute__((availability(macosx,strict,introduced=11.0))) \ | |
| __attribute__((availability(ios,strict,introduced=14.0))) \ | |
| __attribute__((availability(tvos,strict,introduced=14.0))) \ | |
| __attribute__((availability(watchos,strict,introduced=7.0))) | |
| # if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 110000) || \ | |
| (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 140000) || \ | |
| (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 140000) || \ | |
| (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 70000) | |
| # define _LIBCPP_AVAILABILITY_DISABLE_FTM___cpp_lib_atomic_wait | |
| # define _LIBCPP_AVAILABILITY_DISABLE_FTM___cpp_lib_barrier | |
| # define _LIBCPP_AVAILABILITY_DISABLE_FTM___cpp_lib_latch | |
| # define _LIBCPP_AVAILABILITY_DISABLE_FTM___cpp_lib_semaphore | |
| # endif | |
| // This controls the availability of the C++20 format library. | |
| // The library is in development and not ABI stable yet. Currently | |
| // P2216 is aiming to be retroactively accepted in C++20. This paper | |
| // contains ABI breaking changes. | |
| # define _LIBCPP_AVAILABILITY_FORMAT \ | |
| __attribute__((unavailable)) | |
| # define _LIBCPP_AVAILABILITY_DISABLE_FTM___cpp_lib_format | |
| #else | |
| // ...New vendors can add availability markup here... | |
| # error "It looks like you're trying to enable vendor availability markup, but you haven't defined the corresponding macros yet!" | |
| #endif | |
| // Define availability attributes that depend on _LIBCPP_NO_EXCEPTIONS. | |
| // Those are defined in terms of the availability attributes above, and | |
| // should not be vendor-specific. | |
| #if defined(_LIBCPP_NO_EXCEPTIONS) | |
| # define _LIBCPP_AVAILABILITY_FUTURE | |
| # define _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST | |
| # define _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS | |
| # define _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS | |
| #else | |
| # define _LIBCPP_AVAILABILITY_FUTURE _LIBCPP_AVAILABILITY_FUTURE_ERROR | |
| # define _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST _LIBCPP_AVAILABILITY_BAD_ANY_CAST | |
| # define _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS | |
| # define _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS _LIBCPP_AVAILABILITY_BAD_VARIANT_ACCESS | |
| #endif | |
| #endif // _LIBCPP___AVAILABILITY |