Re: [avr-libc-dev] Should cli() imply a memory barrier?

[Joerg Wunsch]

As Jan Waclawek wrote:

> > _MemoryBarrier() (can sometimes be useful).

> Is this something already implemented in the compiler, or are you
> just preparing for future?

It's always been there: it's an empty inline asm instruction with a
"memory" clobber.

> Maybe this sounds trivial, but what about an exact definition of
> what the MemoryBarrier() is supposed to mean, first?

http://en.wikipedia.org/wiki/Memory_barrier

(The explanation there is a little CPU-centric, but similar aspects
also apply to the compiler.)
-- 
cheers, J"org               .-.-.   --... ...--   -.. .  DL8DTL

http://www.sax.de/~joerg/                        NIC: JW11-RIPE
Never trust an operating system you don't have sources for. ;-)