This afternoon we did the final re-branch of swift-4.0-branch from master for the ‘swift’ repository. All further changes for the Swift 4 release that will change either the compiler or Standard Library need to be made as pull requests against this branch.
The following repositories have not done their final re-branch yet, and content going into master for these repositories will still be included in Swift 4 until they finally re-branch:
For the time being, master will automerge to swift-4.0-branch for the swift-corelibs-* repositories, and swift-package-manager will periodically merge from master to swift-4.0-branch. Further communication will be sent out when the final branch dates for those repositories are determined, but they will likely be in July.