member only of
member only of
Atomically replaces the current value with the result of arithmetic subtraction of the value and
arg. The operation is read-modify-write operation. Memory is affected according to the value of
Integral types, arithmetic is defined to use two’s complement representation. There are no undefined results.
T* types, the result may be an undefined address, but the operation otherwise has no undefined behavior. The program is ill-formed if
T is not an object type.
For floating-point types, the floating-point environment in effect may be different from the calling thread's floating-point environment. The operation need not be conform to the corresponding std::numeric_limits traits but is encouraged to do so. If the result is not a representable value for its type, the result is unspecified but the operation otherwise has no undefined behavior.
The volatile-qualified versions are deprecated if std::atomic<T>::is_always_lock_free is false.
|arg||-||the other argument of arithmetic subtraction|
|order||-||memory order constraints to enforce|
 Return value
The value immediately preceding the effects of this function in the modification order of
 Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
|DR||Applied to||Behavior as published||Correct behavior|
|P0558R1||C++11||arithmetic permitted on pointers to cv void or function||made ill-formed|
 See also
| subtracts a non-atomic value from an atomic object and obtains the previous value of the atomic |