Rust Ffi Lint Triage

When to use

Use this skill when CI fails in cargo clippy --all-targets -- -W warnings -D warnings, especially in vsomeip-sys or other binding-heavy code.

Triage order

1. Fix warnings at source when practical:
   • replace deprecated/older patterns (for example std::io::Error::new(...Other...) -> std::io::Error::other(...))
   • use preferred iterator forms (for example next_back() where clippy suggests it)
   • clean doc formatting and genuinely unused code/variables
2. For FFI/generated-binding constraints, use narrow allowances:
   • prefer method-level #[allow(...)] over module/crate-level suppression
   • document why the allowance is required by wrapper semantics
3. Avoid broad suppression unless unavoidable for generated interop behavior.

Generated-binding policy

• Prefer fixes in handwritten wrapper/glue layers first; keep allowances narrow and local.
• Avoid editing generated binding files directly unless regeneration is explicitly in scope.
• If regeneration is in scope, keep generated changes isolated and document the regeneration command in the PR notes.

Validation loop

1. source build/envsetup.sh highest
2. cargo clippy --all-targets -- -W warnings -D warnings
3. If clippy passes, run cargo test -- --test-threads 1 to ensure behavior remains intact.

Decision notes to include in PR

• Which warnings were fixed at source
• Which lint allowances were added and why they are narrowly scoped
• Any known tradeoffs or follow-up cleanups