synchronized { }

[Lionello Lunesu]

"Walter Bright" <newshound1 at digitalmars.com> wrote in message 
news:g3uqph$2s3n$1 at digitalmars.com...
> Right now, if you use a synchronized statement with no argument, it will 
> sync on a mutex unique to that statement.
>
> Does anyone write threading code that depends on this behavior?

Never understood that one, so: no.

But I do think there's a place for synchronized { }: memory barrier.

IIRC a mutex always implies a memory barrier anyway. synchronized without 
argument could only create a memory barrier. This could then be used to 
achieve what the Interlocked* functions in Win32 do. It's such a basic 
operation that I think it warrants a language construct.

static int b;//some global
int a;//local
// native cross-platform InterlockedIncrement
synchronized
{
   a = b++;
}

I should note however that I'm currently having a hard-time implementing 
some multi-threaded algorithms.. I probably don't know enough about MT to be 
messing with it :S

L.