@safe leak fix?

[Brad Roberts]

On Wed, 11 Nov 2009, Walter Bright wrote:

> So it occurred to me that the same solution for closures can be used here. If
> the address is taken of a stack variable in a safe function, that variable is
> instead allocated on the heap. If a more advanced compiler could prove that
> the address does not escape, it could be put back on the stack.
> 
> The code will be a little slower, but it will be memory safe. This change
> wouldn't be done in trusted or unsafe functions.

I think safe vs unsafe causing a behavior change is a really bad idea.  
They're contracts / constraints, not modifiers.

- Brad