EXC_BAD_INSTRUCTION awating Task.sleep

Trying to use the following ObservableObject backed by an actor and getting an error when awaiting Task.sleep

EXC_BAD_INSTRUCTION (code=EXC_I386_INVOP, subcode=0x0)

Any ideas?

class Reader: ObservableObject {
    static let shared = Reader(actor: .init())

    let actor: TestActor
    @Published var val = 0

    @MainActor func read() async {
        val = await actor.val
    }

    func increment() async -> Bool {
        await actor.increment()
        await read()
        return true
    }

    init(actor: TestActor) {
        self.actor = actor
    }
}

actor TestActor {

    var val = 0

    func increment() async {
        let oldval = val
        await Task.sleep(2000000000) // Error here!
        val += 1
    }

}```