| // This source file is part of the Swift.org open source project |
| // |
| // Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors |
| // Licensed under Apache License v2.0 with Runtime Library Exception |
| // |
| // See https://swift.org/LICENSE.txt for license information |
| // See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors |
| |
| // RUN: not %target-swift-frontend %s -typecheck |
| |
| // Issue found by https://github.com/zneak (zneak) |
| |
| protocol A { typealias B } |
| class C : A { typealias B = Int } |
| |
| func crash<D: C>() -> Bool { |
| let a: D.B? = nil |
| } |