\mysection{Conclusion\label{sec:conclusion}} The \TOOL specification language and checking system makes it easier to unit test concurrent data structures written for the C/C++11 memory model. It extends and modifies classic approaches to defining the desired behaviors of concurrent data structures with respect to sequential versions of the same data structure to apply to the C/C++ memory model. Our evaluation shows that the approach can be used to specify and test correctness properties for a range of data structures including a lock-free hashtable, work-stealing deque, queues and locks.