This is a tracking issue for the target_has_atomic_equal_alignment CFG flag which was added in #76965 for Atomic*::from_mut.

It indicates whether an AtomicX has the same alignment as the equivalent X integer type. On some 32-bit platforms (e.g. x86) AtomicI64 has an alignment of 8 while i64 is only aligned to 4 bytes.

Potential design concerns:

• Open question of whether a dedicated cfg is necessary over cfg(accessible) on the from_mut method specifically, which is what is currently gated on this cfg