Annex D (normative) Compatibility features [depr]

D.24 Deprecated atomic operations [depr.atomics]

D.24.3 Operations on atomic types [depr.atomics.types.operations]

#define ATOMIC_VAR_INIT(value) see below
The macro expands to a token sequence suitable for constant initialization of an atomic variable of static storage duration of a type that is initialization-compatible with value.
This operation may need to initialize locks.
— end note
Concurrent access to the variable being initialized, even via an atomic operation, constitutes a data race.
atomic<int> v = ATOMIC_VAR_INIT(5);
— end example