Re: [PATCH 4/11] use ether_addr_equal_64bits

Johannes Berg
2014-01-06T10:18:12Z

On Mon, 2014-01-06 at 10:09 +0100, Julia Lawall wrote:

> > BUILD_BUG_ON(sizeof(struct foo) - offsetof(struct foo, addr) < 8);
> >
> > with the user(s?) and that should catch the scenario I was worrying
> > about?
>
> OK, thanks. That is what I had in mind. But I was hoping to be able to
> put it with the structure.

Right - you might be able to do that with BUILD_BUG_ON_ZERO() as you
pointed out, I haven't looked at these macros in a while.

> Perhaps there is a way to make a macro that
> expands to a dummy function that contains the BUILD_BUG_ON? But I guess
> that would waste space?
>
> I think that 8 should be 16?

No, that should be ETH_ALEN+2 really, I guess - it's not taking into
account the size of the address member itself at all.

johannes