Revert complications in asMemberOf

We needed fairly specific code to make the refinement based
hk encoding work without cyclic references. With the new
encoding these complications are no longer needed.

Author: odersky

src/dotty/tools/dotc/core/SymDenotations.scala

@@ -92,11 +92,6 @@ trait SymDenotations { this: Context =>
         explain("denotation is not a SymDenotation")
     }
   }
-
-  /** An anonymous type denotation with an info `>: Nothing <: Any`. Used to
-   *  avoid stackoverflows when computing members of TypeRefs
-   */
-  lazy val anyTypeDenot = new JointRefDenotation(NoSymbol, TypeBounds.empty, Period.allInRun(ctx.runId))
 }
 
 object SymDenotations {

src/dotty/tools/dotc/core/Types.scala

@@ -1594,26 +1594,10 @@ object Types {
       }
     }
 
-    protected def asMemberOf(prefix: Type)(implicit ctx: Context): Denotation = {
-      // we might now get cycles over members that are in a refinement but that lack
-      // a symbol. Without the following precaution i974.scala stackoverflows when compiled
-      // with new hk scheme.
-      // TODO: Do we still need the complications here?
-      val savedDenot = lastDenotation
-      val savedSymbol = lastSymbol
-      if (prefix.isInstanceOf[RecThis] && name.isTypeName) {
-        lastDenotation = ctx.anyTypeDenot
-        lastSymbol = NoSymbol
-      }
-      try
-        if (name.isShadowedName) prefix.nonPrivateMember(name.revertShadowed)
-        else prefix.member(name)
-      finally
-        if (lastDenotation eq ctx.anyTypeDenot) {
-          lastDenotation = savedDenot
-          lastSymbol = savedSymbol
-        }
-    }
+    protected def asMemberOf(prefix: Type)(implicit ctx: Context): Denotation =
+      if (name.isShadowedName) prefix.nonPrivateMember(name.revertShadowed)
+      else prefix.member(name)
+
 
     /** (1) Reduce a type-ref `W # X` or `W { ... } # U`, where `W` is a wildcard type
      *  to an (unbounded) wildcard type.