Subj : Re: A question about atomic_ptr
To   : comp.programming.threads
From : Peter Dimov
Date : Tue Apr 12 2005 02:45 am

Joe Seigh wrote:
>
> You could, though you've in effect merged atomic_ptr and local_ptr
> together. As a practical matter, I'd think you'd want some mechanism
> to distinguish between shared global pointers and non-shared local
> pointers.

I'm not sure.

I can see how "thread safety is part of the type" can be useful.

But on the other hand "int" offers "basic" thread safety by default and 
"strong" thread safety if I only touch it with atomic_load_acq and 
atomic_store_rel.

Of course in Java "int" is basic and "volatile int" is strong.

For some reason I think that the "non-Java int" (and raw pointer) semantics 
make more sense for shared_ptr; it seems sufficiently primitive to me. I may 
be wrong, of course.

This is also why I'm not particularly fond of Alexander's atomic<> dedicated 
wrapper type. Providing atomic access via ordinary functions seems more 
natural.

.