[hugojosealmeida]

Summary

The freebsd (14.3) job failed because FreeBSD removes release artifacts from download.freebsd.org when a release reaches end-of-life, so fetching 14.3-RELEASE/src.txz returned HTTP 404 and set -e aborted the script before either build path could run.

The FreeBSD matrix now uses the supported 14.5 and 15.1 releases. The source-set fetch first tries download.freebsd.org and, if that fails, retries the same release from archive.freebsd.org/old-releases, removing any partial file first. The Cirrus FreeBSD matrix was also moved off the retired 14.3 image, and its kernel-source clone now runs only when the expected kern_lockf.c is actually missing, deriving the releng/* branch from uname -r.

Changes

• .github/workflows/build.yml: replace 14.3 with 14.5 in the FreeBSD matrix and add the archived-source fallback when the main mirror fetch fails.
• .cirrus.yml: replace the EOL FreeBSD images with 14.5 and 15.1, and make the kernel-source clone conditional on the required kern_lockf.c being absent.

Verification

• ruby -e 'require "yaml"; ...' -> both .github/workflows/build.yml and .cirrus.yml parse successfully.
• Extracted the workflow fetch block and executed it with mocked uname/fetch/tar -> on a simulated 14.3 main-mirror failure it fetched https://archive.freebsd.org/old-releases/amd64/14.3-RELEASE/src.txz; on a simulated 14.5 success it fetched only the main mirror.
• python3 HEAD requests -> 14.5-RELEASE/src.txz and 15.1-RELEASE/src.txz return 200 from download.freebsd.org; the archived 14.3 source returns 200 from archive.freebsd.org.
• git diff --check -> clean.

Risks / Follow-ups

• The FreeBSD VM jobs were not executed locally; the PR CI run is needed to confirm both vmactions entries pass end-to-end.
• The fallback triggers on any main-mirror fetch failure, not only HTTP 404. This is intentional for resilience; a failing archive fetch still aborts the job.

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This PR is AI Assisted.

Closes #372