v1.1.3: portable-atomic polyfill for mipsel-softfloat (real fix this time)#46
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v1.1.2 reached cargo build inside the mipsel docker this time (YAML-fold bug finally out of the way) and surfaced the real underlying problem: MIPS32 has no native 64-bit atomic instructions, so std::sync::atomic::AtomicU64 doesn't exist on mipsel-unknown-linux-musl. Three call sites (DomainFronter stats counters + the request-cache) failed to resolve the import. Fix: depend on `portable-atomic` with the `fallback` feature and import AtomicU64 from there instead of std. The API is identical (same associated methods, same Ordering accepted), so the two touched files change only the `use` line. On 64-bit targets portable-atomic compiles down to the native 64-bit atomic insns with no overhead; on MIPS32 it uses a global spinlock, which is fine for counter increments that happen a few times per relay. Cache.rs and domain_fronter.rs both updated. No other callers of AtomicU64 in non-cfg-gated code (android_jni.rs has it but is gated `#![cfg(target_os = "android")]`, so mipsel-linux-musl never sees it). `cargo test --lib` / `cargo build` still pass on host.
therealaleph
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Apr 25, 2026
v1.1.2 reached cargo build inside the mipsel docker this time (YAML-fold bug finally out of the way) and surfaced the real underlying problem: MIPS32 has no native 64-bit atomic instructions, so std::sync::atomic::AtomicU64 doesn't exist on mipsel-unknown-linux-musl. Three call sites (DomainFronter stats counters + the request-cache) failed to resolve the import. Fix: depend on `portable-atomic` with the `fallback` feature and import AtomicU64 from there instead of std. The API is identical (same associated methods, same Ordering accepted), so the two touched files change only the `use` line. On 64-bit targets portable-atomic compiles down to the native 64-bit atomic insns with no overhead; on MIPS32 it uses a global spinlock, which is fine for counter increments that happen a few times per relay. Cache.rs and domain_fronter.rs both updated. No other callers of AtomicU64 in non-cfg-gated code (android_jni.rs has it but is gated `#![cfg(target_os = "android")]`, so mipsel-linux-musl never sees it). `cargo test --lib` / `cargo build` still pass on host.
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Summary
v1.1.2 finally got the docker/rustup/cargo plumbing right — and exposed the actual root problem I'd been missing across three retags:
std::sync::atomic::AtomicU64doesn't exist on mipsel because MIPS32 has no native 64-bit atomic instructions.Fix: swap
std::sync::atomic::AtomicU64→portable_atomic::AtomicU64in the two non-gated call sites (src/cache.rs+src/domain_fronter.rs).portable-atomicwith thefallbackfeature polyfills u64 atomics via a spinlock on 32-bit MIPS; on 64-bit / armv7 / everywhere else it compiles down to native instructions with no overhead. API is identical, so nothing else changes.android_jni.rsalso uses AtomicU64 but is#![cfg(target_os = "android")]so mipsel-linux-musl never compiles it.Test plan
cargo test --libon 1.1.3 — 54 passingcargo build --bin mhrv-rs— clean