False positive warning when returning a tuple of wildcard type

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Welcome to Scala 2.12.1 (Java HotSpot(TM) 64-Bit Server VM, Java 1.8.0_102).
Type in expressions for evaluation. Or try :help.

scala> val (a, b) = (getClass, getClass)
<console>:11: warning: inferred existential type (Class[?0], Class[?0]) forSome { type ?0 <: type; type ?0 <: type }, which cannot be expressed by wildcards,  should be enabled
by making the implicit value scala.language.existentials visible.
This can be achieved by adding the import clause 'import scala.language.existentials'
or by setting the compiler option -language:existentials.
See the Scaladoc for value scala.language.existentials for a discussion
why the feature should be explicitly enabled.
       val (a, b) = (getClass, getClass)
           ^
a: Class[_ <: type] = class 
b: Class[_ <: type] = class 

[scabug]

Imported From: https://issues.scala-lang.org/browse/SI-10142?orig=1
Reporter: @Atry
Affected Versions: 2.12.1