Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Don't relocate Apple Silicon bottles for default prefix #19384

Open
wants to merge 4 commits into
base: master
Choose a base branch
from
Open

Don't relocate Apple Silicon bottles for default prefix #19384

wants to merge 4 commits into from
+46 −2

Conversation

samuelarogbonlo
Copy link

This change skips the relocation process for bottles on Apple Silicon Macs when using the default prefix (/opt/homebrew). Relocation was initially needed for Intel Macs to avoid wide-reaching replacements with false positives, but is unnecessary for Apple Silicon where the default prefix is unique.

Benefits:

  • Simplifies and speeds up bottle pouring on Apple Silicon
  • Potentially enables code-signing of homebrew-core packages
  • Improves security by avoiding binary modification post-build

A --force-bottle-relocation flag is added for edge cases where relocation might still be needed.

Fixes #19247

  • Have you followed the guidelines in our Contributing document?
  • Have you checked to ensure there aren't other open Pull Requests for the same change?
  • Have you added an explanation of what your changes do and why you'd like us to include them?
  • Have you written new tests for your changes? Here's an example.
  • Have you successfully run brew style with your changes locally?
  • Have you successfully run brew typecheck with your changes locally?
  • Have you successfully run brew tests with your changes locally?

@samuelarogbonlo
Don't relocate Apple Silicon bottles for default prefix
78c3bf9 
This change skips the relocation process for bottles on Apple Silicon Macs
when using the default prefix (/opt/homebrew). Relocation was initially
needed for Intel Macs to avoid wide-reaching replacements with false positives,
but is unnecessary for Apple Silicon where the default prefix is unique.

Benefits:
- Simplifies and speeds up bottle pouring on Apple Silicon
- Potentially enables code-signing of homebrew-core packages
- Improves security by avoiding binary modification post-build

A --force-bottle-relocation flag is added for edge cases where
relocation might still be needed.

Fixes Homebrew#19247
MikeMcQuaid
MikeMcQuaid reviewed Feb 26, 2025
View reviewed changes
Copy link
Member

@MikeMcQuaid MikeMcQuaid left a comment

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Thanks @samuelarogbonlo! Looks good so far. I suspect a bit more work required here and may need to do a gradual rollout with e.g. ENV.fetch("HOMEBREW_BOTTLE_SKIP_RELOCATION_ARM64", false) or something.

@cho-m and other @Homebrew/maintainers may be able to suggest some next steps here.

As discussed already: this should probably do something along the lines of:

  • see if any binary files need relocation with RubyMacho. if so: can skip text relocation. if not: can do text relocation.
  • store whether relocation happened or not in e.g. the bottle manifest or the tab

Shout if you have more questions or we can help more here. Thanks for the PR ❤️

@carlocab
Copy link
Member

Agree regarding more work here. My view is that what we really want for arm64 is to move bottle relocation from bottle-creation time to bottle-pour time. It'll be a no-op for default prefix installations, but still works largely the same way for users with alternative prefixes.

@samuelarogbonlo
Copy link
Author

Based on the feedback, I've updated the implementation to:

  1. Remove the --force-bottle-relocation flag as suggested
  2. Add an environment variable (HOMEBREW_BOTTLE_SKIP_RELOCATION_ARM64) for gradual rollout
  3. Default to the current behavior (no skipping) until the feature is explicitly enabled

For the next steps, I'd like to address the remaining suggestions:

  1. Implement binary file relocation detection using RubyMacho to check if binaries actually need relocation before skipping
  2. Store whether relocation was skipped in the bottle manifest/tab
  3. Consider moving bottle relocation from bottle-creation time to bottle-pour time for arm64 as suggested by @carlocab

I'd appreciate some guidance on how to best implement these remaining items, particularly around using RubyMacho for analyzing binaries, and the preferred approach for tracking relocation status in the bottle metadata. Are there examples in the existing codebase I should look at for reference?

@carlocab
Copy link
Member

Hey @samuelarogbonlo, thanks for giving this a go!

I don't think I'll have answers to all your questions, but I'll try to give you more detailed guidance in a few days. Feel free to ping me this weekend as a reminder.

@samuelarogbonlo
Copy link
Author

Hey @samuelarogbonlo, thanks for giving this a go!

I don't think I'll have answers to all your questions, but I'll try to give you more detailed guidance in a few days. Feel free to ping me this weekend as a reminder.

@carlocab This is a friendly reminder. Thanks

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Reviewers

@MikeMcQuaid MikeMcQuaid MikeMcQuaid left review comments

At least 1 approving review is required to merge this pull request.

Assignees
No one assigned
Labels
None yet
Projects
None yet
Milestone
No milestone
Development

Successfully merging this pull request may close these issues.

Don't relocate Apple Silicon bottles for default prefix
3 participants
@samuelarogbonlo @carlocab @MikeMcQuaid