     }
   }
 
-  Derived().foo() as C1
+  _ = Derived().foo() as C1
   expectEqual("Derived.foo() -> C1", which)
 
-  Derived().foo() as C1?
+  _ = Derived().foo() as C1?
   expectEqual("Derived.foo() -> C1", which)
 }
 

  // Derived().foo() as P1 // error: ambiguous use of 'foo()'
  // expectEqual("Derived.foo() -> P1x", which)

  Derived().foo() as P1x
  expectEqual("Derived.foo() -> P1x", which)
}


    }
  }

  _ = Derived().foo() as C1
  expectEqual("Derived.foo() -> C1x", which)

  _ = Derived().foo() as C1x
  expectEqual("Derived.foo() -> C1x", which)
}

