@retroactive unnecessary?

[mattmassicotte]

I'm having some trouble understanding a build failure with the current package.

The issue is this line:

// ERROR: 'retroactive' attribute does not apply; 'Sendable' is declared in this module
extension RetroactiveColorComponents: @retroactive @unchecked Sendable {
}

But, I do not understand it. RetroactiveColorComponents is declared in a different module, and the type is not publically Sendable in that module. This did build at one point. I'm testing with Xcode 16.1b2.

Am I mis-using @retroactive here?

[mattmassicotte]

I think this is swiftlang/swift#75412