Bridge methods in AnyVals

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I assume this is a new incarnation of #6260. Affects 2.11.5

trait XX[+This] extends Any {
  def repr: This
}

class Id[+T](val t: T) extends AnyVal with XX[Id[T]] {
  def repr = this
}

/*
[error] /Users/dlwh/src/breeze/math/src/main/scala/breeze/newindex/xx.scala:31: bridge generated for member method repr: ()breeze.newindex.Id[T] in class Id
[error] which overrides method repr: ()This in trait XX
[error] clashes with definition of the member itself;
[error] both have erased type ()Object
[error]   def repr = new Id(t)
*/

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Imported From: https://issues.scala-lang.org/browse/SI-9166?orig=1
Reporter: @dlwh
Affected Versions: 2.11.5

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@dlwh said:
actually possibly this is just impossible?

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@retronym said:
Yep, this is simply not possible to support. The fix for #6260 avoids the need for a bridge method in an anoynmous subclass of FunctionN by exactly implementing the interface method. But if you have a named type this isn't possible, as a client of Id#repr will expect repr to return an unboxed Id.

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@retronym said:
Well, it is not quite impossible: an alternative encoding for value classes in which the unboxed versions of methods had mangled names, in the same spirit as specialization would allow this.

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@dlwh said:
Thanks! sorry for the noise.