[v3] system_error, round one

[Paolo Carlini]

Benjamin Kosnik wrote:

> This is a preliminary implementation of <system_error>. The testing is 
> not finished, and I believe there to be some issues with the current 
> specification.
>
> Nevertheless, I thought I'd post this so that others would know that 
> I'm  working on this issue.

Indeed, good idea, thanks!

Benjamin, your additional exports reminded me a very long standing minor 
issue of our library: we have  got __verify_grouping, which isn't a 
template, neither is inline, but isn't exported from the library, 
instead is declared static. That means will be duplicated in each user 
binary, sigh. Can you see anything wrong with simply moving it in locale 
.cc file and export it? Or something else?

Thanks,
Paolo.