framework/tests/framework/GenericTest1.java

import org.checkerframework.framework.testchecker.util.*;

// Test case for Issue 131:
// https://github.com/typetools/checker-framework/issues/131
public class GenericTest1 {
  public interface Foo<T> {}

  public interface Bar<T, C, E extends Foo<C>> extends Foo<T> {}

  public <T> void test(Foo<T> foo) {
    Bar<?, ?, ?> bar =
        foo instanceof Bar<?, ?, ?>
            // TODO flow: support instanceof / cast flow.
            // Warning only with -AcheckCastElementType.
            // TODO:: warning: (cast.unsafe)
            ? (Bar<?, ?, ?>) foo
            : null;
  }
}