shared - i need it to be useful

[Manu]

On Mon, Oct 22, 2018 at 7:35 AM Timon Gehr via Digitalmars-d
<digitalmars-d at puremagic.com> wrote:
>
> On 22.10.18 16:09, Simen Kjærås wrote:
> > On Monday, 22 October 2018 at 13:40:39 UTC, Timon Gehr wrote:
> >> module reborked;
> >> import atomic;
> >>
> >> void main()@safe{
> >>     auto a=new Atomic!int;
> >>     import std.concurrency;
> >>     spawn((shared(Atomic!int)* a){ ++*a; }, a);
> >>     ++a.tupleof[0];
> >> }
> >
> > Finally! Proof that MP is impossible. On the other hand, why the hell is
> > that @safe? It breaks all sorts of guarantees about @safety. At a
> > minimum, that should be un- at safe.
> >
> > Filed in bugzilla: https://issues.dlang.org/show_bug.cgi?id=19326
> >
> > --
> >    Simen
>
> Even if this is changed (and it probably should be), it does not fix the
> case where the @safe function is in the same module. I don't think it is
> desirable to change the definition of @trusted such that you need to
> check the entire module if it contains a single @trusted function.
>
> If I can break safety of some (previously correct) code by editing only
> @safe code, then that's a significant blow to @safe. I think we need a
> general way to protect data from being manipulated in @safe code in any
> way, same module or not.

I'm all ears.