Some polishings

Author: odersky

compiler/src/dotty/tools/dotc/core/CheckRealizable.scala

@@ -21,8 +21,6 @@ object CheckRealizable {
 
   object NotConcrete extends Realizability(" is not a concrete type")
 
-  object NotStable extends Realizability(" is not a stable reference")
-
   class NotFinal(sym: Symbol)(implicit ctx: Context)
   extends Realizability(i" refers to nonfinal $sym")
 

compiler/src/dotty/tools/dotc/core/TypeComparer.scala

@@ -406,10 +406,10 @@ class TypeComparer(initctx: Context) extends ConstraintHandling {
             if (cls2 eq AnyKindClass) return true
             if (tp1.isRef(NothingClass)) return true
             if (tp1.isLambdaSub) return false
-            if (cls2 eq AnyClass) return true
               // Note: We would like to replace this by `if (tp1.hasHigherKind)`
               // but right now we cannot since some parts of the standard library rely on the
               // idiom that e.g. `List <: Any`. We have to bootstrap without scalac first.
+            if (cls2 eq AnyClass) return true
             if (cls2 == defn.SingletonClass && tp1.isStable) return true
             return tryBaseType(cls2)
           }