RCArray is unsafe

[Walter Bright via Digitalmars-d]

On 3/1/2015 12:51 PM, Michel Fortin wrote:
> That's actually not enough. You'll have to block access to global variables too:
>
>      S s;
>
>      void main() {
>          s.array = RCArray!T([T()]);   // s.array's refcount is now 1
>          foo(s.array[0]);           // pass by ref
>      }
>      void foo(ref T t) {
>          s.array = RCArray!T([]);      // drop the old s.array
>          t.doSomething();              // oops, t is gone
>      }

Thinking about it, there are many other ways this can happen. At the moment, I'm 
stuck thinking of a solution other than requiring foo() to be pure. Anyone have 
ideas?