Emit trait method bodies in statics

And use this as the target of the default methods or
statically resolved super or $init calls.

The call-site change is predicated on `-Yuse-trait-statics`
as a stepping stone for experimentation / bootstrapping.

I have performed this transformation in the backend,
rather than trying to reflect this in the view from
Scala symbols + ASTs.

We also need to add an restriction related to invokespecial to Java
parents: to support a super call to one of these to implement a
super accessor, the interface must be listed as a direct parent
of the class.

The static method names has a trailing $ added to avoid duplicate
name and signature errors in classfiles.

1 files changed, 21 insertions, 0 deletions

diff --git a/test/files/neg/trait-defaults-super.scala b/test/files/neg/trait-defaults-super.scala
new file mode 100644
index 0000000000..def271e8e7
--- /dev/null
+++ b/test/files/neg/trait-defaults-super.scala
@@ -0,0 +1,21 @@
+trait T extends java.lang.Iterable[String] {
+
+  override def spliterator(): java.util.Spliterator[String] = {
+    super[Iterable].spliterator
+    super.spliterator
+    null
+  }
+  def foo = {
+    super[Iterable].spliterator
+    super.spliterator
+  }
+  def iterator(): java.util.Iterator[String] = java.util.Collections.emptyList().iterator()
+}
+class C extends T
+object Test {
+  def main(args: Array[String]): Unit = {
+    val t: T = new C
+    t.spliterator
+    t.foo
+  }
+}