incremental.c

void example()
{
    A *a;
    B *b;
 
    a = a_new();
    if (!a){
        puts("bye");
        return;
    }
    b = b_new(a);
    if (!b){
        a_delete(a);
        puts("bye");
        return;
    }

    use_b(b);
    b_delete(b);
    a_delete(a);
    puts("bye");
}