Except for the destructor, member functions of the default allocator shall not introduce data races ([intro.multithread]) as a result of concurrent calls to those member functions from different threads. Calls to these functions that allocate or deallocate a particular unit of storage shall occur in a single total order, and each such deallocation call shall happen before the next allocation (if any) in this order.
Returns: A pointer to the initial element of an array of storage of size n * sizeof(T), aligned appropriately for objects of type T.
Remarks: the storage is obtained by calling ::operator new ([new.delete]), but it is unspecified when or how often this function is called.
Throws: bad_alloc if the storage cannot be obtained.
void deallocate(T* p, size_t n);
Requires: p shall be a pointer value obtained from allocate(). n shall equal the value passed as the first argument to the invocation of allocate which returned p.
Effects: Deallocates the storage referenced by p .
Remarks: Uses ::operator delete ([new.delete]), but it is unspecified when this function is called.