diff --git a/tests/neg/i1650.scala b/tests/neg/i1650.scala
new file mode 100644
index 000000000000..26b8a489ac40
--- /dev/null
+++ b/tests/neg/i1650.scala
@@ -0,0 +1,5 @@
+object Test {
+  test4(test4$default$1) // error
+  def test4[T[P]](x: T[T[List[T[X forSome { type X }]]]]) = ??? // error // error
+  def test4$default$1[T[P]]: T[Int] = ???
+}