25069914 repro

    protocol Testable{}
    class MyObj : Testable{}
    
    class Test {
        var arr:[Testable] = []
        
        func run() {
            arr = [MyObj()] as [MyObj]
            println("arr has \(arr.count) elements")
            for e in arr {  // following access causes EXC_BAD_ACCESS
                println(e)
            }
        }
    }
    
    let t = Test()
    t.run()