什么是“分歧隐含扩展”的scalac消息是什么意思？

val o1: Ordered[Int] = 1
val o2: Ordered[Int] = 2
println(o1 < o2)

当我喂这个scala我得到：

Ordered.scala:3: error: diverging implicit expansion for type scala.math.Ordering[Ordered[Int]]
starting with method ordered in trait LowPriorityOrderingImplicits
println(o1 < o2)
        ^
one error found

使用“-explaintypes”没有任何进一步的.但是,“-Xlog-implicits”给出了以下内容：

math.this.Ordering.comparatorToOrdering is not a valid implicit value for scala.math.Ordering[Ordered[Int]] because:
could not find implicit value for parameter cmp: java.util.Comparator[Ordered[Int]]
scala.this.Predef.conforms is not a valid implicit value for Ordered[Int] => java.lang.Comparable[Ordered[Int]] because:
type mismatch;
 found   : <:<[Ordered[Int],Ordered[Int]]
 required: Ordered[Int] => java.lang.Comparable[Ordered[Int]]
/Users/steshaw/Projects/playground/scala/programming-in-scala/Ordered.scala:3: error: diverging implicit expansion for type scala.math.Ordering[Ordered[Int]]
starting with method ordered in trait LowPriorityOrderingImplicits
println(o1 < o2)
        ^
math.this.Ordering.comparatorToOrdering is not a valid implicit value for scala.math.Ordering[Ordered[Int]] because:
could not find implicit value for parameter cmp: java.util.Comparator[Ordered[Int]]
scala.this.Predef.conforms is not a valid implicit value for Ordered[Int] => java.lang.Comparable[Ordered[Int]] because:
type mismatch;
 found   : <:<[Ordered[Int],Ordered[Int]]
 required: Ordered[Int] => java.lang.Comparable[Ordered[Int]]
one error found

但这不是帮助我.想知道这个消息的意思和解决方法？

[更新]今天与Scala 2.11.0相同的代码除了第一个关于“发散隐式扩展”之外还会生成第二个错误消息.这第二个消息是非常有帮助的.

$scala Ordered.scala
Ordered.scala:3: error: diverging implicit expansion for type scala.math.Ordering[Ordered[Int]]
starting with method comparatorToOrdering in trait LowPriorityOrderingImplicits
println(o1 < o2)
        ^
/Users/steshaw/Projects/playground/scala/scalac-errors/Ordered.scala:3: error: type mismatch;
 found   : Ordered[Int]
 required: Int
println(o1 < o2)
             ^
two errors found