[stdatomic.h.syn] (original) (raw)

32 Concurrency support library [thread]

32.5 Atomic operations [atomics]

32.5.12 C compatibility [stdatomic.h.syn]

The header provides the following definitions:

template<class T> using std-atomic = std::atomic<T>; #define _Atomic(T) std-atomic<T> #define ATOMIC_BOOL_LOCK_FREE see below #define ATOMIC_CHAR_LOCK_FREE see below #define ATOMIC_CHAR16_T_LOCK_FREE see below #define ATOMIC_CHAR32_T_LOCK_FREE see below #define ATOMIC_WCHAR_T_LOCK_FREE see below #define ATOMIC_SHORT_LOCK_FREE see below #define ATOMIC_INT_LOCK_FREE see below #define ATOMIC_LONG_LOCK_FREE see below #define ATOMIC_LLONG_LOCK_FREE see below #define ATOMIC_POINTER_LOCK_FREE see below using std::memory_order; using std::memory_order_relaxed; using std::memory_order_consume; using std::memory_order_acquire; using std::memory_order_release; using std::memory_order_acq_rel; using std::memory_order_seq_cst; using std::atomic_flag; using std::atomic_bool; using std::atomic_char; using std::atomic_schar; using std::atomic_uchar; using std::atomic_short; using std::atomic_ushort; using std::atomic_int; using std::atomic_uint; using std::atomic_long; using std::atomic_ulong; using std::atomic_llong; using std::atomic_ullong; using std::atomic_char8_t; using std::atomic_char16_t; using std::atomic_char32_t; using std::atomic_wchar_t; using std::atomic_int8_t; using std::atomic_uint8_t; using std::atomic_int16_t; using std::atomic_uint16_t; using std::atomic_int32_t; using std::atomic_uint32_t; using std::atomic_int64_t; using std::atomic_uint64_t; using std::atomic_int_least8_t; using std::atomic_uint_least8_t; using std::atomic_int_least16_t; using std::atomic_uint_least16_t; using std::atomic_int_least32_t; using std::atomic_uint_least32_t; using std::atomic_int_least64_t; using std::atomic_uint_least64_t; using std::atomic_int_fast8_t; using std::atomic_uint_fast8_t; using std::atomic_int_fast16_t; using std::atomic_uint_fast16_t; using std::atomic_int_fast32_t; using std::atomic_uint_fast32_t; using std::atomic_int_fast64_t; using std::atomic_uint_fast64_t; using std::atomic_intptr_t; using std::atomic_uintptr_t; using std::atomic_size_t; using std::atomic_ptrdiff_t; using std::atomic_intmax_t; using std::atomic_uintmax_t; using std::atomic_is_lock_free; using std::atomic_load; using std::atomic_load_explicit; using std::atomic_store; using std::atomic_store_explicit; using std::atomic_exchange; using std::atomic_exchange_explicit; using std::atomic_compare_exchange_strong; using std::atomic_compare_exchange_strong_explicit; using std::atomic_compare_exchange_weak; using std::atomic_compare_exchange_weak_explicit; using std::atomic_fetch_add; using std::atomic_fetch_add_explicit; using std::atomic_fetch_sub; using std::atomic_fetch_sub_explicit; using std::atomic_fetch_and; using std::atomic_fetch_and_explicit; using std::atomic_fetch_or; using std::atomic_fetch_or_explicit; using std::atomic_fetch_xor; using std::atomic_fetch_xor_explicit; using std::atomic_flag_test_and_set; using std::atomic_flag_test_and_set_explicit; using std::atomic_flag_clear; using std::atomic_flag_clear_explicit; #define ATOMIC_FLAG_INIT see below using std::atomic_thread_fence; using std::atomic_signal_fence;

Each using-declaration for some name A in the synopsis above makes available the same entity as std​::​Adeclared in .

Each macro listed above other than _Atomic(T)is defined as in .

It is unspecified whether makes available any declarations in namespace std.

Neither the _Atomic macro, nor any of the non-macro global namespace declarations, are provided by any C++ standard library header other than .

Recommended practice: Implementations should ensure that C and C++ representations of atomic objects are compatible, so that the same object can be accessed as both an _Atomic(T)from C code and an atomic<T> from C++ code.

The representations should be the same, and the mechanisms used to ensure atomicity and memory ordering should be compatible.