[LLVMdev] C as used/implemented in practice: analysis of responses

[David Keaton]

On 07/02/2015 03:17 AM, Kuperstein, Michael M wrote:
> You want to redefine ["won't break the program"], by specifying a new abstract machine, which is
> more conservative than standard C/C++. The proper way to do that would,
> I believe, be to work towards setting up a working group within the
> relevant committees, and come up with a uniformly accepted definition
> for this abstract machine, which could then be implemented (assuming
> there is, indeed, wide enough agreement in the implementer community –
> something that does not look at all likely) by next-generation compilers.

      This work has already been done in Annex L of the C standard, 
which provides an optional stricter abstract machine.  As far as I know, 
no implementations have attempted to support Annex L yet.

> Point is – I think you’re barking up the wrong tree.
>
> This isn’t an llvm-dev issue, it’s a standards committee issue.

      Because the standards work has been done, the ball is back in the 
implementations' court.  That doesn't mean Annex L should be the default 
behavior.  It would be nice to have it as an option, though.

					David