The lifetime (
[basic.life]) of an object referenced by
*ptr
shall exceed the lifetime of all
atomic_refs that reference the object
. While any
atomic_ref instances exist
that reference the
*ptr object,
all accesses to that object shall exclusively occur
through those
atomic_ref instances
. No subobject of the object referenced by
atomic_ref
shall be concurrently referenced by any other
atomic_ref object
.