Keith Bauer

Was trying to implement one of these behaviors myself (one sequence's elements consumed once each by multiple concurrent consumers) [in this thread](https://forums.swift.org/t/crash-in-safe-swift-with-actors-concurrency/64496) and got sent here to make a feature...

We need something like this to exist in the short term (ideally 5.9!); we need to be able to enforce the strictest available concurrency checking and still have the package...

I agree in principle that Apple have shot themselves in the foot here, but I'm somewhat unconvinced by the current state of your lint: 1. SwiftPM is clearly broken here;...

Relevant to my questions, [it seems like](https://github.com/swiftlang/swift-syntax/blob/main/Sources/SwiftSyntax/Documentation.docc/Macro%20Versioning.md) * the dependency on swiftsyntax should be declared as a range, eg. "509.1.0"..

The crash appears to occur when Swift 6 built code is responsible for creating the type metadata (even though it gets it from the type metadata accessor in the framework?!)....

@hborla not sure why "concurrency"? AFAICT, nothing here is related to concurrency?

Haha it was Concurrency after all 😅

Breaking change in a major OS version to be more correct: good Breaking change in *any* OS version that causes existing financial apps to show incorrect monetary amounts to customers:...

Apple has internal infrastructure to do a runtime check whether the running app was "linked on or after" a particular SDK version. This is normally how they stage breaking changes...