Location

https://doc.rust-lang.org/nightly/core/sync/atomic/struct.AtomicBool.html

Summary

The introductory section for AtomicBool states:

This type has the same size, alignment, and bit validity as a bool.

But later the safety requirements for from_ptr state:

ptr must be aligned to align_of::<AtomicBool>() (note that on some platforms this can be bigger than align_of::<bool>()).

This seems to be a contradiction. If AtomicBool has the same alignment as bool then how can align_of::<AtomicBool>() be bigger than align_of::<bool>().