> Er, that footnote says that those are *precluded*, not permitted (though
> of course as a footnote it is not normative).
I think it's an "out" because the footnote only covers data in "separate memory locations." Two chars that don't cross an alignment boundary would be in the same "memory location" in some sense. They're in the same atomically-readable space.
But I don't know if that's the intent. If not, I think C11 has a serious issue. It will require ABI changes and that's not going to make people happy.