Merge pull request #6118 from dotty-staging/fix-#4376

Fix #4376: Add regression test

Author: odersky

tests/neg/4376.scala

@@ -0,0 +1,6 @@
+object App {
+  type Id[A] >: A <: A
+
+  val a: Array[_ >: Id[_ <: Int]] =
+    (Array.ofDim[String](1) : Array[_ >: Id[Nothing]]) // error
+}