`AntiAliasing` complains that `b` is aliased when calling `inner`: ```scala object InnerFnsAliasing { case class Box(var value: Int) def outer(b: Box): Unit = { def inner(v: Int): Unit = { require(b.value == v) } inner(b.value) // Illegal passing of aliased local variable: b } } ``` Here, we are passing a value of an immutable type to `inner`, as such, `b` is not aliased.