Plan for Exceptions and @nogc?

[Chris Williams via Digitalmars-d]

On Tuesday, 17 February 2015 at 15:54:17 UTC, Andrei Alexandrescu 
wrote:
> On 2/16/15 3:17 PM, Jonathan Marler wrote:
>> Is there a proposal for how D will support throwing Exceptions 
>> in @nogc
>> code in the future?
>
> Nothing definite. We will get on to that right after 2.067. 
> This is a good time to start discussions. -- Andrei

Could someone give a description of the minutiae of why Exception 
throwing uses memory allocation as it is and why (for example) 
passing it back on the stack isn't an option?