Accessor仅在Swift 1.2 / 2.0 Release版本中提供了错误的值

import Foundation

enum Level : Int {
    case
    Bad     = 0,Normal  = 1,Good    = 2,Superb  = 3
}

struct Attribute : Printable {
    var x : Level = .Normal
    var y : Level = .Normal
    var z : Level = .Normal
    var w : Level = .Normal

    var description : String {
        return "((x.rawValue),(y.rawValue),(z.rawValue),(w.rawValue))"
    }

    func toString() -> String {
        return description
    }
}


var AccessorBugTestSingleton : AccessorBugTest!

class AccessorBugTest {

    let index       : Int
    var attributes  : [Attribute] = []
    var todaysAttributes : Attribute {
        get {
            let r = attributes[index]
            println("today: (r)")
            return r
        }
    }
    var initialText : String = ""
    // selection for key
    var states  : [String:Int] = ["x": 0,"y": 0,"z": 0,"w": 0]
    var descriptions  : [String:Int] = ["a": 0,"b": 0,"c": 0,"d": 0]


    init() {
        index = 10
        for i in 1...31 {
            var att = Attribute(x: .Superb,y: .Superb,z: .Superb,w: .Superb)
            attributes.append(att)
        }

        let attribs = todaysAttributes
        initialText = "(attribs)"
        println("init: (attribs),(self.attributes[index])")
    }

}

实例化AccessorBugTest时,应该打印

init: (3,3,3),(3,3)

但在Release版本中打印,

init: (3,0),3)

如果我删除未使用的属性状态和描述,那么问题是固定的,不知道为什么.此外,如果我使用x,y,z,w而不是枚举,那么它再次正常工作.

知道发生了什么事吗？

我已将程序上传到：https://github.com/endavid/AccessorBugTest
它包含一个测试用例,如果你在Release配置中运行它将失败(转到Program – > Scheme – > Edit Scheme,并将Test更改为Release而不是Debug).

我还下载了Xcode 7.1 beta,在Swift 2.0中试过,问题仍然存在:(