[MikeMcQuaid]

Read preserve_rpath from the installed formula because API metadata omits it and rewriting bundled dylib IDs can overflow their Mach-O headers.

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Codex with GPT 6 Astra at Extra High effort, with local review and testing.

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[coderabbitai]

No actionable comments were generated in the recent review.

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Commits

Reviewing files that changed from the base of the PR and between 6969bb3 and 60d111f.

Files selected for processing: 3

• Library/Homebrew/extend/os/mac/keg_relocate.rb
• Library/Homebrew/keg_relocate.rb
• Library/Homebrew/test/keg_spec.rb

Files with no reviewable changes: 1

• Library/Homebrew/extend/os/mac/keg_relocate.rb

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📝 Summary

Summary by CodeRabbit

• Bug Fixes
  • Improved macOS library relocation so Swift library identifiers and @rpath identifiers are preserved when enabled by a formula.
  • Improved handling when formula information is unavailable, allowing relocation to continue without applying the preservation setting.

formula_preserve_rpath? moved from the macOS Keg extension to the shared Keg implementation. The method checks the installed formula first, falls back to lookup by formula name, and returns false when the formula is unavailable. Specs cover each lookup outcome.

Changes: Formula preserve_rpath lookup

Layer / File(s)	Summary
Formula lookup and fallback behaviour Library/Homebrew/keg_relocate.rb, Library/Homebrew/extend/os/mac/keg_relocate.rb, Library/Homebrew/test/keg_spec.rb	The shared Keg implementation checks the installed formula’s preserve_rpath? value, then falls back to lookup by formula name. It returns false if formula loading raises FormulaUnavailableError. The specs cover installed-formula preference, fallback lookup, and unavailable formulas.

Priority: Normal

Merge Risk: Minimal · up to 60d11

The change reads preserve_rpath from the installed formula and falls back to name lookup. No actionable merge-blocking risk remains.

Pre-merge checks: 4

Check name	Status	Explanation
Title check		The title clearly describes the main change: using the installed formula to honour rpath preservation.
Description check		The description explains what the change does and why it is needed. It directly relates to the changeset and mentions the associated Mach-O header risk.
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.

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[krehel]

Thanks!