Concurrency errors from GeneratedAssetSymbols?

I'm getting concurrency warnings from code I didn't write, but rather was generated for me. The code is in GeneratedAssetSymbols in my Xcode project. All I did was drag in an image named "fencerGrid" into the asset catalogue and then try to reference the image in my code:

Image(uiImage: UIImage(imageLiteralResourceName: "fencerGrid")).resizable().scaleEffect(0.25)

When I build, I see a warning coming from this code, which I assume is auto-generated on my behalf:

@available(iOS 17.0, macOS 14.0, tvOS 17.0, watchOS 10.0, *)
extension DeveloperToolsSupport.ImageResource {

    /// The "fencerGrid" asset catalog image resource.
    static let fencerGrid = DeveloperToolsSupport.ImageResource(name: "fencerGrid", bundle: resourceBundle)


The above generates the warning:
Static property 'fencerGrid' is not concurrency-safe because it is not either conforming to 'Sendable' or isolated to a global actor; this is an error in Swift 6

How do I deal with this since I'm not writing the code?

Since those types are out of your control there's not much you can do and it's really the responsibility of Apple to fix the warning. You can either live with it for now, or you can do something that is not really recommended as a stop-gap:

extension DeveloperToolsSupport.ImageResource: @unchecked Sendable {}

But I would recommend hiding that in a #if swift(<6.0) check because hopefully Xcode 16 fixes the real issue.

According to the release notes, this is resolved in Xcode 15.4.

  • Fixed an issue where generated asset symbols emitted warnings with Swift strict concurrency checking enabled. (124156187)

Ah, I'm on 15.3. Didn't realize 15.4 was out.