C++ traps that D2 doesn't avoid yet?

[Walter Bright]

Steven Schveighoffer wrote:
> Even experienced developers fall into some of these traps.  I know I 
> occasionally fell into this trap:
> 
> if(x);
>   x->doSomething();
> 
> But no more with D, because it's not allowed.  Those kinds of things can be 
> easily prevented, and are common mistakes by all programmers.

Here's another fun one:

     printf("%d\n", 8l);

What does that print?