fix(relay): gate the per-worker accept loop on _quic

[kixelated]

Problem

Since #3927, serve in rs/moq-relay/src/relay.rs is only called by the QUIC worker group (#[cfg(feature = "_quic")]), so a build without _quic flags it as dead code and -D warnings fails. Quest agents in #3966 hit it via just check.

Change

Gate serve on _quic and fix its stale comment (it has no external callers).

Public API / wire: none.

(written by Opus 5.5)

🤖 Generated with Claude Code

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-23T17:49:14.900631Z	1fdc22a	PR opened

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[kixelated]

MERGE

Positive improvement: yes. After #3927, serve is only invoked from the QUIC worker path (member.serve(... serve(...)) under #[cfg(feature = "_quic")]). Leaving the free function unguarded makes non-_quic builds treat it as dead code and fail under -D warnings (as Quest agents hit in #3966 via just check). Gating the function matches how the rest of this file already splits QUIC vs non-QUIC paths.

Worth the complexity: yes. One #[cfg(feature = "_quic")] plus a comment that no longer claims external callers. No public API or wire change.

Different approach: not needed. Moving serve into an existing _quic module would be more churn for the same compile-time outcome. Keeping it next to serve_listening is fine.

Recommendation: merge as-is.

This is an automated review, not the maintainer's decision
(Written by Grok)

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ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Advanced

Run ID: 1fd9cee7-3bcb-43df-88ae-5635485f9c5a

📥 Commits

Reviewing files that changed from the base of the PR and between 7ee2b02 and 1fdc22a.

📒 Files selected for processing (1)

• rs/moq-relay/src/relay.rs

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Walkthrough

The relay serve function is now compiled only when the _quic feature is enabled. Its documentation now states that each QUIC worker binds its own listener, while Relay::run binds the shared listener before readiness.

Merge Risk: ⚪ Minimal · up to 1fdc2

The change gates the per-worker accept loop on QUIC and clarifies listener ownership. The shared non-QUIC accept path remains available, so no merge-blocking regression is identified; the change is mergeable after normal checks.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly identifies the main change: gating the relay accept loop on the _quic feature.
Description check	✅ Passed	The description explains the dead-code warning problem, the _quic gating change, the stale comment update, and the absence of public API or wire changes.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 1 functions across 1 files.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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