[santhiprakash]

This Pull Request fixes/closes #3045.

It changes the following:

• AsyncStatus::generation (the status cache-invalidation counter) now uses std::sync::atomic::AtomicUsize instead of AtomicU64, which only exists on targets with 64-bit atomics and therefore broke the build on 32-bit targets (reported on powerpc-apple-darwin; i686-unknown-linux-gnu and friends fail the same way).

I followed the checklist:

• I added unittests
• I ran make check without errors
• I tested the overall application
• I added an appropriate item to the changelog

Root cause

The generation counter is only a cache-invalidation token: it is loaded with Ordering::Relaxed, folded into the request key via hash(&(params, generation)), and bumped with fetch_add(1, Ordering::Relaxed) after each completed fetch. crate::hash is generic over T: Hash and produces the u64 request key through DefaultHasher::finish(), so nothing downstream assumes the counter is 64 bits wide.

Fix

Switched the counter to AtomicUsize — pointer-width atomics are available on every supported target, and the sibling pending field in the same struct already uses it. No new dependency is needed. A theoretical wrap at 2^32 on 32-bit targets is benign since the value is only an opaque token in the request hash. No behaviour change on 64-bit targets.

Verification

There is no 32-bit CI job, so I verified against a real 32-bit target (powerpc-unknown-linux-gnu, same class as the reporter's powerpc-apple-darwin):

• before: cargo check --target powerpc-unknown-linux-gnu -p asyncgit fails with error[E0432]: unresolved import std::sync::atomic::AtomicU64 at asyncgit/src/status.rs:13
• after: the same command checks asyncgit cleanly
• make check green: cargo fmt --check, cargo clippy --workspace --all-features, cargo nextest run --workspace (318/318 passed), tombi format --check, cargo deny check
• CI: the full workflow matrix (22 jobs: ubuntu/macos/windows × nightly/stable/1.88, plus lints/udeps/musl/arm/apple-x86 builds) passes on my fork: https://github.com/santhiprakash/gitui/actions/runs/40570456408 — the upstream run is awaiting the usual first-time-contributor approval

No unit tests were added since the change is a type substitution with identical runtime semantics; the existing workspace test suite continues to pass.