ARM bare-metal programming in D (cont) - volatile

[Arjan]

On Thursday, 24 October 2013 at 00:43:11 UTC, Mike wrote:
> Hello again,
>
> I'm interested in ARM bare-metal programming with D, and I'm 
> trying to get my head wrapped around how to approach this.  I'm 
> making progress, but I found something that was surprising to 
> me: deprecation of the volatile keyword.
>
> In the bare-metal/hardware/driver world, this keyword is 
> important to ensure the optimizer doesn't cache reads to 
> memory-mapped IO, as some hardware peripheral may modify the 
> value without involving the processor.
>
> I've read a few discussions on the D forums about the volatile 
> keyword debate, but noone seemed to reconcile the need for 
> volatile in memory-mapped IO.  Was this an oversight?
>
> What's D's answer to this?  If one were to use D to read from 
> memory-mapped IO, how would one ensure the compiler doesn't 
> cache the value?

This article might also give some insight in the problems with 
volatile:
http://blog.regehr.org/archives/28