diff options
| -rw-r--r-- | libstdc++-v3/include/std/atomic | 17 | ||||
| -rw-r--r-- | libstdc++-v3/include/std/version | 1 | ||||
| -rw-r--r-- | libstdc++-v3/testsuite/29_atomics/atomic/lock_free_aliases.cc | 34 |
3 files changed, 52 insertions, 0 deletions
diff --git a/libstdc++-v3/include/std/atomic b/libstdc++-v3/include/std/atomic index 356f145..857f927 100644 --- a/libstdc++-v3/include/std/atomic +++ b/libstdc++-v3/include/std/atomic @@ -1727,6 +1727,23 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION using __atomic_ref<_Tp>::operator=; }; +#define __cpp_lib_atomic_lock_free_type_aliases 201907L +#ifdef _GLIBCXX_HAVE_PLATFORM_WAIT + using atomic_signed_lock_free + = atomic<make_signed_t<__detail::__platform_wait_t>>; + using atomic_unsigned_lock_free + = atomic<make_unsigned_t<__detail::__platform_wait_t>>; +#elif ATOMIC_INT_LOCK_FREE || !(ATOMIC_LONG_LOCK_FREE || ATOMIC_CHAR_LOCK_FREE) + using atomic_signed_lock_free = atomic<signed int>; + using atomic_unsigned_lock_free = atomic<unsigned int>; +#elif ATOMIC_LONG_LOCK_FREE + using atomic_signed_lock_free = atomic<signed long>; + using atomic_unsigned_lock_free = atomic<unsigned long>; +#elif ATOMIC_CHAR_LOCK_FREE + using atomic_signed_lock_free = atomic<signed char>; + using atomic_unsigned_lock_free = atomic<unsigned char>; +#endif + #endif // C++2a /// @} group atomics diff --git a/libstdc++-v3/include/std/version b/libstdc++-v3/include/std/version index 3c7c440..61718eb 100644 --- a/libstdc++-v3/include/std/version +++ b/libstdc++-v3/include/std/version @@ -187,6 +187,7 @@ #define __cpp_lib_assume_aligned 201811L #define __cpp_lib_atomic_flag_test 201907L #define __cpp_lib_atomic_float 201711L +#define __cpp_lib_atomic_lock_free_type_aliases 201907L #define __cpp_lib_atomic_ref 201806L #define __cpp_lib_atomic_value_initialization 201911L #define __cpp_lib_bind_front 201907L diff --git a/libstdc++-v3/testsuite/29_atomics/atomic/lock_free_aliases.cc b/libstdc++-v3/testsuite/29_atomics/atomic/lock_free_aliases.cc new file mode 100644 index 0000000..02c4ccc --- /dev/null +++ b/libstdc++-v3/testsuite/29_atomics/atomic/lock_free_aliases.cc @@ -0,0 +1,34 @@ +// { dg-options "-std=gnu++20" } +// { dg-do compile { target c++20 } } + +#include <atomic> + +#ifndef __cpp_lib_atomic_lock_free_type_aliases +# error "Feature test macro for lock-free type aliases is missing in <atomic>" +#elif __cpp_lib_atomic_lock_free_type_aliases != 201907L +# error "Feature test macro for lock-free type aliases has wrong value in <atomic>" +#endif + +template<typename T> +constexpr bool is_atomic_specialization = false; +template<typename T> +constexpr bool is_atomic_specialization<std::atomic<T>> = true; + +// The type aliases atomic_signed_lock_free and atomic_unsigned_lock_free +// name specializations of atomic +static_assert( is_atomic_specialization<std::atomic_signed_lock_free> ); +static_assert( is_atomic_specialization<std::atomic_unsigned_lock_free> ); + +#include <type_traits> + +// ... whose template arguments are integral types, +static_assert( std::is_integral_v<std::atomic_signed_lock_free::value_type> ); +static_assert( std::is_integral_v<std::atomic_unsigned_lock_free::value_type> ); + +// ... respectively signed and unsigned, +static_assert( std::is_signed_v<std::atomic_signed_lock_free::value_type> ); +static_assert( std::is_unsigned_v<std::atomic_unsigned_lock_free::value_type> ); + +// and whose is_always_lock_free property is true. +static_assert( std::atomic_signed_lock_free::is_always_lock_free ); +static_assert( std::atomic_unsigned_lock_free::is_always_lock_free ); |