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### 14.2.4.1 Self-References Are Ordered

A given CPU will see its own accesses as occurring in ``program order'', as if the CPU was executing only one instruction at a time with no reordering or speculation. For older CPUs, this restriction is necessary for binary compatibility, and only secondarily for the sanity of us software types. There have been a few CPUs that violate this rule to a limited extent, but in those cases, the compiler has been responsible for ensuring that ordering is explicitly enforced as needed.

Either way, from the programmer's viewpoint, the CPU sees its own accesses in program order.