Inherent code performance advantages of D over C?

[Francesco Cattoglio]

On Monday, 16 December 2013 at 17:32:11 UTC, deadalnix wrote:
> On Monday, 16 December 2013 at 00:53:21 UTC, Walter Bright
>> Good idea. I suggest writing a pull request against the 
>> documentation for this.
>
> That is a bad idea as it preclude any GC optimization based on 
> immutability.

What do you mean by this? How can a change in the documentation 
preclude GC optimization? Does our GC read docs to understand 
what can be collected? Now I get it: it's a stop the world, then 
RTFM, then collect GC implementation :)