libkern/OSAtomic.h

@header These are deprecated legacy interfaces for atomic and synchronization operations. Define OSATOMIC_USE_INLINED=1 to get inline implementations of the OSAtomic interfaces in terms of the <stdatomic.h> primitives. Define OSSPINLOCK_USE_INLINED=1 to get inline implementations of the OSSpinLock interfaces in terms of the <os/lock.h> primitives. These are intended as a transition convenience, direct use of those primitives should be preferred.