Tests fail on 32-bit about vm-memory HOT 2 CLOSED

Now with vm-memory 0.12 release, it fails in a more difficult way on debian, notable on armel (which also don't have AtomicU64):

https://ci.debian.net/data/autopkgtest/testing/armel/r/rust-vhost-user-backend/35901107/log.gz

234s error[E0432]: unresolved import `std::sync::atomic::AtomicU64`
234s  --> /usr/share/cargo/registry/vm-memory-0.12.0/src/bitmap/backend/atomic_bitmap.rs:6:25
234s   |
234s 6 | use std::sync::atomic::{AtomicU64, Ordering};

Now AtomicU64 is used in actual bitmap implementation, not only in tests. And this fails on platforms where there's no AtomicU64.

from vm-memory.

vm-memory does not currently support anything but 64-bit. We are making it more explicit with #275. I would recommend to restrict the package to 64-bit on debian.

Adding 32-bit support may be possible, but so far nobody has stated interest and code assumes 64-bit in a couple of places. So if 32bit support is desired I would recommend filing a new issue to discuss what is needed and how it could be pulled off.

from vm-memory.