Unexpected warning when comparing with `java.lang.Object`

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When I compare a java.lang.Object with a Scala type, the Scala compiler report the following warning:

Object and com.thoughtworks.binding.Binding.BindingSeq[String] are unrelated: they will most likely never compare equal

The warning is incorrect. The comparison does return true for my case.

• Source: https://github.com/ThoughtWorksInc/Binding.scala/blob/32702da/Binding/src/test/scala/com/thoughtworks/binding/BindingTest.scala#L271
• Build log: https://travis-ci.org/ThoughtWorksInc/Binding.scala/builds/165740647

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Imported From: https://issues.scala-lang.org/browse/SI-9953?orig=1
Reporter: @Atry
Affected Versions: 2.11.8
See #8965

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@SethTisue said:
Is it possible to reproduce the problem in a small, self-contained project or code snippet?

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@som-snytt said:

$ scala
Welcome to Scala 2.11.8 (Java HotSpot(TM) 64-Bit Server VM, Java 1.8.0_92).
Type in expressions for evaluation. Or try :help.

scala> val e = new java.util.EventObject("hi")
e: java.util.EventObject = java.util.EventObject[source=hi]

scala> e.getSource
res0: Object = hi

scala> e.getSource == "hi"
res1: Boolean = true

scala> trait X extends Any
defined trait X

scala> val x = null.asInstanceOf[X]
x: X = null

scala> e.getSource == x
<console>:15: warning: Object and X are unrelated: they will most likely never compare equal
       e.getSource == x
                   ^
res2: Boolean = false

scala> val o = new Object
o: Object = java.lang.Object@6aaa5eb0

scala> o == x
<console>:15: warning: Object and X are unrelated: they will most likely never compare equal
       o == x
         ^
res3: Boolean = false

scala> 

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@Atry said:

Welcome to Scala 2.11.8 (Java HotSpot(TM) 64-Bit Server VM, Java 1.8.0_77).
Type in expressions for evaluation. Or try :help.

scala> trait X extends Any 
defined trait X

scala> object O extends X 
defined object O

scala> (O: Object) == (O: X) 
<console>:14: warning: Object and X are unrelated: they will most likely never compare equal
       (O: Object) == (O: X)
                   ^
res0: Boolean = true

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@som-snytt said:
Any Hall. Isn't she lubly?

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@som-snytt said:
scala/scala#5449