private void detectAndDisconnectLoops(@NotNull TopDownAnalysisContext c) {
    // Loop detection and disconnection
    List<Runnable> tasks = new ArrayList<Runnable>();
    for (final MutableClassDescriptorLite klass : c.getClassesTopologicalOrder()) {
      for (final JetType supertype : klass.getSupertypes()) {
        ClassifierDescriptor supertypeDescriptor =
            supertype.getConstructor().getDeclarationDescriptor();
        if (supertypeDescriptor instanceof MutableClassDescriptorLite) {
          MutableClassDescriptorLite superclass = (MutableClassDescriptorLite) supertypeDescriptor;
          if (isReachable(superclass, klass, new HashSet<ClassDescriptor>())) {
            tasks.add(
                new Runnable() {
                  @Override
                  public void run() {
                    klass.getSupertypes().remove(supertype);
                  }
                });
            reportCyclicInheritanceHierarchyError(trace, klass, superclass);
          }
        }
      }
    }

    for (Runnable task : tasks) {
      task.run();
    }
  }
  private void createTypeConstructors(@NotNull TopDownAnalysisContext c) {
    for (Map.Entry<JetClassOrObject, ClassDescriptorWithResolutionScopes> entry :
        c.getClasses().entrySet()) {
      JetClassOrObject classOrObject = entry.getKey();
      MutableClassDescriptor descriptor = (MutableClassDescriptor) entry.getValue();
      if (classOrObject instanceof JetClass) {
        descriptorResolver.resolveMutableClassDescriptor(
            (JetClass) classOrObject, descriptor, trace);
      } else if (classOrObject instanceof JetObjectDeclaration) {
        descriptor.setModality(Modality.FINAL);
        descriptor.setVisibility(
            resolveVisibilityFromModifiers(classOrObject, getDefaultClassVisibility(descriptor)));
        descriptor.setTypeParameterDescriptors(Collections.<TypeParameterDescriptor>emptyList());
      }

      descriptor.createTypeConstructor();

      ClassKind kind = descriptor.getKind();
      if (kind == ClassKind.ENUM_ENTRY
          || kind == ClassKind.OBJECT
          || kind == ClassKind.ENUM_CLASS) {
        MutableClassDescriptorLite classObject = descriptor.getClassObjectDescriptor();
        assert classObject != null
            : "Enum entries and named objects should have class objects: "
                + classOrObject.getText();

        JetType supertype;
        if (kind == ClassKind.ENUM_CLASS) {
          supertype = KotlinBuiltIns.getInstance().getAnyType();
        } else {
          // This is a clever hack: each enum entry and object declaration (i.e. singleton) has a
          // synthetic class object.
          // We make this class object inherit from the singleton here, thus allowing to use the
          // singleton's class object where
          // the instance of the singleton is applicable. Effectively all members of the singleton
          // would be present in its class
          // object as fake overrides, so you can access them via standard class object notation:
          // ObjectName.memberName()
          supertype = descriptor.getDefaultType();
        }
        classObject.setSupertypes(Collections.singleton(supertype));
        classObject.createTypeConstructor();
      }
    }
  }
 // Temporary. Duplicates logic from LazyClassTypeConstructor.isReachable
 private static boolean isReachable(
     MutableClassDescriptorLite from,
     MutableClassDescriptorLite to,
     Set<ClassDescriptor> visited) {
   if (!visited.add(from)) return false;
   for (JetType supertype : from.getSupertypes()) {
     TypeConstructor supertypeConstructor = supertype.getConstructor();
     if (supertypeConstructor.getDeclarationDescriptor() == to) {
       return true;
     }
     ClassifierDescriptor superclass = supertypeConstructor.getDeclarationDescriptor();
     if (superclass instanceof MutableClassDescriptorLite
         && isReachable((MutableClassDescriptorLite) superclass, to, visited)) {
       return true;
     }
   }
   return false;
 }