// RUN: %target-swift-frontend -emit-ir %s // https://github.com/apple/swift/issues/55588 public protocol Book { associatedtype Name } public protocol BookDecorator: Book where Name == DecoratedBook.Name { associatedtype DecoratedBook: Book associatedtype Name = DecoratedBook.Name } public class ConcreteBookDecorator: BookDecorator { public typealias DecoratedBook = T }