2ae06a8d46
val c = C("...")
val d = c
if (c.x == null) return
c.x.length // c.x has type String
d.x.length // d.x -> c.x through d -> c
c = C(null) // remove alias d -> c
d.x.length // info from c.x moved to d.x
^KT-54824 Fixed