dispatch_queue_t    8 src/runtime/gcd_thread_pool.cpp typedef struct dispatch_queue_s *dispatch_queue_t;
dispatch_queue_t   11 src/runtime/gcd_thread_pool.cpp extern dispatch_queue_t dispatch_get_global_queue(
dispatch_queue_t   14 src/runtime/gcd_thread_pool.cpp extern void dispatch_apply_f(size_t iterations, dispatch_queue_t queue,
dispatch_queue_t   16 src/runtime/gcd_thread_pool.cpp extern void dispatch_async_f(dispatch_queue_t queue, void *context, void (*work)(void *));