Fix failing fuzzy test

Author: odersky

compiler/src/dotty/tools/dotc/typer/Namer.scala

@@ -505,7 +505,7 @@ class Namer { typer: Typer =>
    *  @pre `child` must have a position.
    */
   final def addChild(cls: Symbol, child: Symbol)(implicit ctx: Context): Unit = {
-    val childStart = child.pos.start
+    val childStart = if (child.pos.exists) child.pos.start else -1
     def insertInto(annots: List[Annotation]): List[Annotation] =
       annots.find(_.symbol == defn.ChildAnnot) match {
         case Some(Annotation.Child(other)) if other.pos.exists && childStart <= other.pos.start =>

library/src-bootstrapped/scala/Tuple.scala

@@ -473,7 +473,7 @@ object NonEmptyTuple {
 }
 
 @showAsInfix
-sealed class *:[+H, +T <: Tuple] extends Object with  NonEmptyTuple
+sealed class *:[+H, +T <: Tuple] extends NonEmptyTuple
 
 object *: {
   inline def unapply[H, T <: Tuple](x: H *: T) = (x.head, x.tail)