Stack implemented with enum causes Abort trap: 6

Originator:GriotSpeak
Number:rdar://22103992 Date Originated:01-Aug-2015 04:22 PM
Status:Open Resolved:
Product:Developer Tools Product Version:Xcode-beta (7A165t)
Classification:Enhancement Reproducible:Always
 
Summary:
The source included below causes the swift compiler to trap.

Steps to Reproduce:
    enum Stack<T> {
        typealias Element = T
        case Empty
        indirect case Cons(Element, Stack)
    }

    extension Stack {
        var isEmpty: Bool {
            switch self {
            case .Empty:
                return true
            case .Cons:
                return false
            }
        }

        var head:Element? {
            if case let .Cons(theHead, _) = self {
                return theHead
            } else {
                return nil
            }
        }

        var tail:Stack? {
            if case let .Cons(_, theTail) = self {
                return theTail
            } else {
                return nil
            }
        }
    }

Expected Results:
Either successful compilation or errors indicating the problem

Actual Results:
Command failed due to signal: Abort trap: 6

Comments


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