public static void foo(List<? extends Foo> foos) {
  final Comparator<Foo> comparator = createComparator();
  Collections.sort(foos, comparator);
}

private static Comparator<Foo> createComparator() {
  return ...;
}

public interface Foo {
}

IDEA 4188 highlights the method call Collections.sort() in red, where as the compiler does not show an error. Who is right?

Issue was resolved