checker/tests/nullness/SuperConstructorInit.java

import org.checkerframework.checker.nullness.qual.*;

public class SuperConstructorInit {

  String a;

  public SuperConstructorInit() {
    a = "";
  }

  public static class B extends SuperConstructorInit {
    String b;
    // :: error: (initialization.fields.uninitialized)
    public B() {
      super();
      a.toString();
    }
  }
}