library;
import self as self;
import "dart:core" as core;

class A extends core::Object {
  synthetic constructor •() → self::A*
    : super core::Object::•()
    ;
}
class B extends self::A {
  synthetic constructor •() → self::B*
    : super self::A::•()
    ;
}
class C extends core::Object {
  synthetic constructor •() → self::C*
    : super core::Object::•()
    ;
  method f1(self::A* x) → void {}
  method f2([self::A* x = #C1]) → void {}
  method f3({self::A* x = #C1}) → void {}
  method f4() → self::A* {}
}
class D extends self::C {
  synthetic constructor •() → self::D*
    : super self::C::•()
    ;
  method f1(core::Object* x) → void {}
  method f2([core::Object* x = #C1]) → void {}
  method f3({core::Object* x = #C1}) → void {}
  method f4() → self::B* {}
}
class E extends self::C {
  synthetic constructor •() → self::E*
    : super self::C::•()
    ;
  method f1(self::B* x) → void {}
  method f2([self::B* x = #C1]) → void {}
  method f3({self::B* x = #C1}) → void {}
  method f4() → core::Object* {}
}
static method main() → dynamic {}

constants  {
  #C1 = null
}