Remove more code for Mojave and older

[cho-m]

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Remove some more code that is no longer used. This includes older macOS conditional cases and some Xcode 2 handling.

There is some other code for separate_header_package? and provides_sdk? which I need to check if it is safe to make always true.

[Copilot]

Pull Request Overview

This PR removes legacy code related to older macOS versions that are no longer supported. The changes clean up conditional logic that was specific to macOS versions prior to Catalina (10.15), which is now the oldest allowed version according to HOMEBREW_MACOS_OLDEST_ALLOWED.

Key changes:

• Removed Xcode 2.x version detection code
• Simplified version checks by removing conditions for pre-Catalina macOS versions
• Standardized behavior across all supported macOS versions

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
Library/Homebrew/os/mac/xcode.rb	Removed Xcode 2.x version detection logic and simplified separate_header_package? to remove macOS version check
Library/Homebrew/extend/os/mac/hardware.rb	Simplified oldest_cpu method to return :nehalem for all non-Ventura+ versions
Library/Homebrew/extend/os/mac/dev-cmd/bottle.rb	Removed macOS version check in tar_args to always use modern tar flags

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[MikeMcQuaid]

Thanks! A few questions but can self-merge if I'm wrong.

[MikeMcQuaid]

Thanks, looks good once feedback addressed!

[Copilot]

Pull Request Overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

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[Copilot]

Pull Request Overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated no new comments.

Comments suppressed due to low confidence (1)

Library/Homebrew/os/mac.rb:171

• The comment describing expected results for sdk_path_if_needed is now outdated. Since sdk_root_needed? always returns true and the logic no longer checks for separate_header_package?, cases 2-5 no longer apply. The method now always returns the SDK path (either Xcode or CLT) when either is installed. The comment should be updated to reflect the simplified behavior.

    def self.sdk_path_if_needed(version = nil)
      # Prefer CLT SDK when both Xcode and the CLT are installed.
      # Expected results:
      # 1. On Xcode-only systems, return the Xcode SDK.
      # 2. On Xcode-and-CLT systems where headers are provided by the system, return nil.
      # 3. On CLT-only systems with no CLT SDK, return nil.
      # 4. On CLT-only systems with a CLT SDK, where headers are provided by the system, return nil.
      # 5. On CLT-only systems with a CLT SDK, where headers are not provided by the system, return the CLT SDK.

      return unless sdk_root_needed?

      sdk_path(version)
    end

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[cho-m]

I'll look into sdk_root_needed? in a follow up as that is always true.

It is used in Homebrew/core so will need to clean up formulae first (LLVM and PostgreSQL)

[MikeMcQuaid]

Looks good, thanks!