@preconcurrency import doesn't suppress warning on use of imported global variable

[hborla]

Description

A @preconcurrency import does not suppress the use of an imported global variable.

Reproduction

@preconcurrency import struct UIKit.UIAccessibility.Notification

@MainActor func f() {
     _ = UIAccessibility.Notification.screenChanged // Reference to static property 'screenChanged' is not concurrency-safe because it involves shared mutable state; this is an error in Swift 6
}

Expected behavior

The warning is suppressed.

Environment

Swift 5.10

Additional information

No response

[rnapier]

I've discovered an important detail and this may not be a bug.

The full code I was using included:

import SwiftUI
@preconcurrency import ... // whatever out of UIKit

Since SwiftUI imports UIKit (I assume), this doesn't work as expected. Rearranging fixes it:

@preconcurrency import UKit
import SwiftUI

This is a bit of a papercut for devs, but I don't think it's a bug.

[mattmassicotte]

Here is an issue specifically capturing the ordering of imports being significant: #64392

[mattmassicotte]

With Swift 6 this does suppress the warning, but now incorrectly produces a diagnotic saying that the @preconcurrency attribute has no effect.

swift-driver version: 1.109.2 Apple Swift version 6.0 (swiftlang-6.0.0.3.300 clang-1600.0.20.10)
Target: arm64-apple-macosx14.0

[DougGregor]

The ordering issue is addressed by #74413, but we're not modeling the submodule import (of UIKit.UIAccessibility) completely.

[mattmassicotte]

I both really appreciate the fix and also the follow up explaining the scope of when it currently will/won't apply.