@Embeddable
public class ParentEmbeddable<MyType extends MyTypeInterface> {
    private Set<MyType> fields;
    // setters, getters...
}

@Generated(value = "org.hibernate.jpamodelgen.JPAMetaModelEntityProcessor")
@StaticMetamodel(ParentEmbeddable.class)
public abstract class ParentEmbeddable_ {
	public static volatile SetAttribute<ParentEmbeddable, MyTypeInterface> fields;
}

@Embeddable
public class ChildEmbeddable extends ParentEmbeddable<MyTypeImpl> {
}

Execution failed for task ':generateJpaMetaModel'.
> java.lang.ClassCastException: com.sun.tools.javac.code.Symbol$TypeVariableSymbol cannot be cast to javax.lang.model.element.TypeElement