Unexpected behaviour with @warn_unqualified_access and Swift 6

Originator:jcparis
Number:rdar://FB16272848 Date Originated:2025-01-09
Status:Open Resolved:
Product:Swift Product Version:6
Classification:Incorrect/Unexpected Behavior Reproducible:Yes
 
Given a function `foo` defined in an extension of `View`, when marking it with `@warn_unqualified_access` like this:
```
struct ContentView: View {
    var body: some View {
        Text("Hello, world!")
            .foo()
    }
}

extension View {
    @warn_unqualified_access
    func foo() -> some View {
        self.padding()
    }
}
```

When compiling with Swift 6, the following warning triggers: 
```
warning: use of 'foo' treated as a reference to instance method in protocol 'View'
        .foo()
         ^
```

It doesn't trigger (as expected) on Swift 5.
It is also trigger on Swift 5 with StrictConcurrency upcoming feature flag enabled (unexpected).

Comments


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