On Mon, 20 Jun 2011, Alexander Holler wrote:

Am 20.06.2011 20:39, schrieb Alan Stern:

quoted

On Mon, 20 Jun 2011, Alexander Holler wrote:

quoted

I see it that way: packed is needed to be sure that at least for struct
ehci_regs there are no padding bytes inbetween the members.

But is it _really_ needed?

quoted

It might
work without, but that depends on the compiler (-version, architecture,
whatever).

Have there _ever_ been _any_ combinations of compiler, version,
architecture, whatever, that had unwanted padding bytes in this
structure?

I don't know. But if there would be no doubts, this discussion would not 
happen and I assume there never would have been an attribute packed there.

Don't be so sure.  That is very old code; the attribute could easily 
have been present for no good reason.

Alan Stern