## Why
The Bazel workflow has multiple jobs that run concurrently for the same
target triple. In particular, the Windows `test`, `clippy`, and
`verify-release-build` jobs could all miss and then attempt to save the
same Bazel repository cache key:
```text
bazel-cache-${target}-${lockhash}
```
Because `actions/cache` entries are immutable, only one job can reserve
that key. The others can report failures such as:
```text
Failed to save: Unable to reserve cache with key bazel-cache-x86_64-pc-windows-gnullvm-..., another job may be creating this cache.
```
Adding only the workflow name would not separate these jobs because they
all run inside the same `Bazel` workflow. The key needs a job-level
namespace as well.
## What Changed
- Added a required `cache-scope` input to
`.github/actions/prepare-bazel-ci/action.yml`.
- Moved Bazel repository cache key construction into the shared action
and exposed the computed key as `repository-cache-key`.
- Exposed the exact restore result as `repository-cache-hit` so save
steps can skip exact cache hits.
- Updated `.github/workflows/bazel.yml` to pass `cache-scope: bazel-${{
github.job }}` for the `test`, `clippy`, and `verify-release-build`
jobs.
- The scoped restore key is now the only fallback. This avoids carrying
a temporary restore path for the old unscoped cache namespace.
## Verification
- Parsed `.github/actions/prepare-bazel-ci/action.yml` and
`.github/workflows/bazel.yml` with Ruby's YAML parser.
- `actionlint` is not installed in this workspace, so I could not run a
GitHub Actions semantic lint locally.
## Why
`main` recently needed
[#17691](https://github.com/openai/codex/pull/17691) because code behind
`cfg(not(debug_assertions))` was not being compiled by the Bazel PR
workflow. Our existing CI only built the fast/debug configuration, so
PRs could stay green while release-only Rust code still failed to
compile. This PR adds a release-style compile check that is cheap enough
to run on every PR.
## What Changed
- Added a `verify-release-build` job to `.github/workflows/bazel.yml`.
- Represented each supported OS once in that job's matrix: x64 Linux,
arm64 macOS, and x64 Windows.
- Kept the build close to fastbuild cost by using
`--compilation_mode=fastbuild` while forcing Rust to compile with
`-Cdebug-assertions=no`, which makes `cfg(not(debug_assertions))` true
without also turning on release optimizations or debug-info generation.
- Added comments in `.github/workflows/bazel.yml` and
`scripts/list-bazel-release-targets.sh` to make the job's intent and
target scope explicit.
- Restored the Bazel repository cache save behavior to run after every
non-cancelled job, matching
[#16926](https://github.com/openai/codex/pull/16926), and removed the
now-unused `repository-cache-hit` output from `prepare-bazel-ci`.
- Reused the shared `prepare-bazel-ci` action from the parent PR so the
new job does not duplicate Bazel setup boilerplate.
## Verification
- Used `bazel aquery` on `//codex-rs/tui:codex-tui` to confirm the Rust
compile still uses `opt-level=0` and `debuginfo=0` while passing
`-Cdebug-assertions=no`.
- Parsed `.github/workflows/bazel.yml` as YAML locally.
- Ran `bash -n scripts/list-bazel-release-targets.sh`.
## Why
This stack adds a new Bazel CI lane that verifies Rust code behind
`cfg(not(debug_assertions))`, but adding that job directly to
`.github/workflows/bazel.yml` would duplicate the same setup in multiple
places. Extracting the shared setup first keeps the follow-up change
easier to review and reduces the chance that future Bazel workflow edits
drift apart.
## What Changed
- Added `.github/actions/prepare-bazel-ci/action.yml` as a composite
action for the Bazel job bootstrap shared by multiple workflow jobs.
- Moved the existing Bazel setup, repository-cache restore, and
execution-log setup behind that action.
- Updated the `test` and `clippy` jobs in `.github/workflows/bazel.yml`
to call `prepare-bazel-ci`.
- Exposed `repository-cache-hit` and `repository-cache-path` outputs so
callers can keep the existing cache-save behavior without duplicating
the restore step.
## Verification
- Parsed `.github/workflows/bazel.yml` as YAML locally after rebasing
the stack.
- CI will exercise the refactored jobs end to end.
---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/17704).
* #17705
* __->__ #17704
