Fix for #4188.

It seems to arise from the changes to inner objects which make them look
like lazy vals. I am not sure this is the right change but at least
it's only about a six character diff to review. Closes #4188, review by
odersky.

1 files changed, 6 insertions, 0 deletions

diff --git a/test/files/pos/bug4188.scala b/test/files/pos/bug4188.scala
new file mode 100644
index 0000000000..40e7d4924e
--- /dev/null
+++ b/test/files/pos/bug4188.scala
@@ -0,0 +1,6 @@
+class A {
+  object Ding
+  class B {
+    (null: Any) match { case _: Ding.type => () }
+  }
+}