Dispatch tvOS 11.4 to 12.0 API Differences

object.h

Added #def DISPATCH_DECL_SUBCLASS

queue.h

Added dispatch_queue_global_t

Added OS_dispatch_queue_global

Added dispatch_queue_serial_t

Added OS_dispatch_queue_serial

Added dispatch_queue_main_t

Added OS_dispatch_queue_main

Added dispatch_queue_concurrent_t

Added OS_dispatch_queue_concurrent

Added #def DISPATCH_APPLY_QUEUE_ARG_NULLABILITY

Modified dispatch_apply()

	Declaration
From	void dispatch_apply(size_t iterations, dispatch_queue_t _Nonnull queue, void (^ _Nonnull)(size_t) block)
To	void dispatch_apply(size_t iterations, dispatch_queue_t _Nullable queue, void (^ _Nonnull)(size_t) block)

Modified dispatch_apply_f()

	Declaration
From	void dispatch_apply_f(size_t iterations, dispatch_queue_t _Nonnull queue, void * _Nullable context, void (* _Nonnull)(void * _Nullable, size_t) work)
To	void dispatch_apply_f(size_t iterations, dispatch_queue_t _Nullable queue, void * _Nullable context, void (* _Nonnull)(void * _Nullable, size_t) work)

Modified dispatch_get_main_queue()

	Declaration
From	dispatch_queue_t _Nonnull dispatch_get_main_queue(void)
To	dispatch_queue_main_t _Nonnull dispatch_get_main_queue(void)

Modified dispatch_get_global_queue()

	Declaration
From	dispatch_queue_t _Nonnull dispatch_get_global_queue(long identifier, unsigned long flags)
To	dispatch_queue_global_t _Nonnull dispatch_get_global_queue(long identifier, unsigned long flags)

time.h

Added DISPATCH_WALLTIME_NOW