`nonisolated(unsafe)` properties redundant for stored properties

We used to have to mark types as @unchecked Sendable when they couldn't otherwise be proven safe to the compiler via normal means. I believe I read somewhere that we could instead now mark the type as Sendable and then annotate necessary properties as nonisolated(unsafe).

I know this is a bad example but just to illustrate:

final class X {}

struct Foo: Sendable {
  nonisolated(unsafe) var _value: X?

However, this generates two warnings in Xcode 15.3 with complete concurrency checking enabled.

'nonisolated' is redundant on struct's stored properties; this is an error in Swift 6

Stored property '_value' of 'Sendable'-conforming struct 'Foo' has non-sendable type 'X?'

Did I entirely make this up? Or perhaps I've done something wrong?


I think I saw a bug fix here for this issue

1 Like

Oh nice find! @hborla do you know if there are any plans to back port fixes of this type to a 5.10.x release? Or should we just hold tight for WWDC :eyes: