how to cast away 'volatile'?
Matthew Woehlke
mw_triad@users.sourceforge.net
Tue Mar 13 20:51:00 GMT 2007
Andrew Haley wrote:
> Matthew Woehlke writes:
> > Andrew Haley wrote:
> > > Michael Eager writes:
> > >> It can also be used to share data between threads, but it becomes
> > >> problematic if accesses are not atomic. It's reasonable to use a
> > >> shared volatile sig_atomic_t to communicate between threads, to say
> > >> "I'm done" or "Start processing".
> > >
> > > Is that really safe, though? There's nothing to stop the machine from
> > > reordering memory writes, even if the compiler doesn't.
> >
> > ...my understanding is that is exactly what 'fence' is for.
>
> That's my understanding too. Here, we're really talking about non-x86
> processors which have much weaker ordering guarantees.
On non-x86 processors I actually resort to pthread mutexes :-) (at least
until/unless I have inline assembly implementations for those...)
So far no one has successfully answered my original question; how do I
suppress these dang warnings? :-)
--
Matthew
HIPPOS feel unacknowledged. HIPPOS get angry.
> PRAISE HIPPOS
HIPPOS seem somewhat placated.
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