This post describes the goals, release process, and estimated schedule for Swift 5.2.
Motivation and Goals
Swift 5.2 is a release meant to include significant quality and performance enhancements.
Snapshots of Swift 5.2
Downloadable snapshots of the Swift 5.2 release branch will be posted
regularly as part of continuous integration testing.
Once Swift 5.2 is released, the official final builds will also be posted in addition to the snapshots.
Getting Changes into Swift 5.2
On December 9, 2019 the
swift-5.2-branch branch will be cut, and this will contain the changes that will be released in Swift
5.2. After the branch is cut, changes can be landed on the branch via pull request if the meet the criteria for the release.
Some notable exceptions to this plan are indicated in the table below. Each will merge from
swift-5.2-branch daily. The final
cutoff date for changes to each exception will extend beyond November 5 and will be announced later.
Philosophy on Taking Changes into Swift 5.2
All language and API changes for Swift 5.2 will go through the Swift
Evolution process. Evolution
proposals should aim to be completed by the branch date in order to
increase their chances of impacting the Swift 5.2 release. Exceptions
will be considered on a case-by-case basis, particularly if they tie
in with the core goal of the release.
Other changes (e.g., bug fixes, diagnostic improvements, SourceKit interface
improvements) will be accepted based on their risk and impact.
Low-risk test tweaks will also be accepted late into the release branch if
it aids in the qualification of the release.
As the release converges, the criteria for accepted changes will become
The following repositories will have a
swift-5.2-branch branch to track
sources as part of Swift 5.2 release:
The overall management of the release will be overseen by the following
individuals, who will announce when stricter control of change goes into
effect for the Swift 5.2 release as the release converges:
Pull Requests for Release Branch
In order for a pull request to be considered for inclusion in the release
swift-5.2-branch) after it has been cut, it must include the following
Explanation: A description of the issue being fixed or enhancement being
made. This can be brief, but it should be clear.
Scope: An assessment of the impact/importance of the change. For
example, is the change a source-breaking language change, etc.
SR Issue: The SR if the change fixes/implements an issue/enhancement on
Risk: What is the (specific) risk to the release for taking this change?
Testing: What specific testing has been done or needs to be done to
further validate any impact of this change?
Reviewer: One or more code owners
for the impacted components should review the change. Technical review can
be delegated by a code owner or otherwise requested as deemed appropriate or
All change going on the
swift-5.2-branch must go through pull requests that are
accepted by the corresponding release manager.