annotation class A : Annotation {
  constructor(x: String = "", y: Int = 42) /* primary */ 
  val x: String
    field = x
    get

  val y: Int
    field = y
    get

}

@A(x = "abc", y = 123)
fun test1() {
}

@A(x = "def")
fun test2() {
}

@A(x = "ghi")
fun test3() {
}

@A(, y = 456)
fun test4() {
}

@A
fun test5() {
}