123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288 |
- // -*- 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.
- //
- // Note that when exceptions are disabled, the methods that normally throw
- // these exceptions can be used even on older deployment targets, but those
- // methods will abort instead of throwing.
- # 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,
- // ::operator delete[], and their align_val_t variants, which were all added
- // in C++17, and hence not present in early dylibs.
- # define _LIBCPP_AVAILABILITY_SIZED_NEW_DELETE
- // This controls the availability of the std::future_error exception.
- //
- // Note that when exceptions are disabled, the methods that normally throw
- // std::future_error can be used even on older deployment targets, but those
- // methods will abort instead of throwing.
- # 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 floating-point std::to_chars functions.
- // These overloads were added later than the integer overloads.
- # define _LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT
- // This controls the availability of the C++20 synchronization library,
- // which requires shared library support for various operations
- // (see libcxx/src/atomic.cpp). This includes <barier>, <latch>,
- // <semaphore>, and notification functions on std::atomic.
- # 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. P2216 is
- // retroactively accepted in C++20. This paper contains ABI breaking
- // changes.
- # define _LIBCPP_AVAILABILITY_FORMAT
- // # define _LIBCPP_AVAILABILITY_DISABLE_FTM___cpp_lib_format
- // This controls whether the library claims to provide a default verbose
- // termination function, and consequently whether the headers will try
- // to use it when the mechanism isn't overriden at compile-time.
- // # define _LIBCPP_HAS_NO_VERBOSE_ABORT_IN_LIBRARY
- #elif defined(__APPLE__)
- # define _LIBCPP_AVAILABILITY_SHARED_MUTEX \
- __attribute__((availability(macos,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
- // Note: bad_optional_access & friends were not introduced in the matching
- // macOS and iOS versions, so the version mismatch between macOS and others
- // is intended.
- # define _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS \
- __attribute__((availability(macos,strict,introduced=10.13))) \
- __attribute__((availability(ios,strict,introduced=12.0))) \
- __attribute__((availability(tvos,strict,introduced=12.0))) \
- __attribute__((availability(watchos,strict,introduced=5.0)))
- # 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(macos,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(macos,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(macos,strict,introduced=10.9))) \
- __attribute__((availability(ios,strict,introduced=7.0)))
- # define _LIBCPP_AVAILABILITY_LOCALE_CATEGORY \
- __attribute__((availability(macos,strict,introduced=10.9))) \
- __attribute__((availability(ios,strict,introduced=7.0)))
- # define _LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR \
- __attribute__((availability(macos,strict,introduced=10.9))) \
- __attribute__((availability(ios,strict,introduced=7.0)))
- # define _LIBCPP_AVAILABILITY_FILESYSTEM \
- __attribute__((availability(macos,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(macos,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_FLOATING_POINT \
- __attribute__((unavailable))
- # define _LIBCPP_AVAILABILITY_SYNC \
- __attribute__((availability(macos,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
- # define _LIBCPP_AVAILABILITY_FORMAT \
- __attribute__((unavailable))
- # define _LIBCPP_AVAILABILITY_DISABLE_FTM___cpp_lib_format
- # define _LIBCPP_HAS_NO_VERBOSE_ABORT_IN_LIBRARY
- #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
|