(Follow-up from Herb posted below.) On 11/30/2012 9:34 PM, Eric Niebler wrote:
So here's the scoop from Herb. There are two separate things: the rolling releases (like the just-released Update 1 which added XP support to VS'12), and the CTP releases (like the one that just that added variadic templates to the compiler). The former are officially supported, go-live products; the latter are not. There is, and should be, *no expectation* that the features delivered in the CTP releases will ever make it into the officially supported updates.
On other words, we should operate under the assumption that there will be no improvements in C++11 compliance of any officially supported Microsoft compiler until the next major release of Visual Studio.
I worded that very carefully. I believe it is 100% accurate. I will be directing Herb's attention to this thread so that he can comment if I got anything wrong.
What that means for Boost is up for us to decide. But given the above, I think it would be wise for us to add support for the CTP releases to Boost.Config using _MSC_FULL_VER so that we don't have to wait until VS.Next to start taking advantage of variadic templates (for example).
And as promised, here is the follow-up from Herb: Herb Sutter wrote:
I think you said it right, the only things I wanted to add were that:
- I'm not recommending either for or against Boost making the CTP a target of interest for Boost. My $0.02 would be you probably wouldn't want to expend that effort since it's just a CTP.
- As I said in my Feb talk, these are "out-of-band (OOB)" CTPs to give people a look at our C++11 progress. Our goal is to try to "go dark" less on customers, and to enable earlier feedback (too often we had an all-too-short time between beta and release to respond to feedback, and this will help).
- The CTP is a separate stream from the new VS Update releases. It's yet TBD whether these will roll into a future VS Update, but since that hasn't been announced you shouldn't count it. DO however count on CTP features being in the next VC++ compiler release -- including betas, and recall our betas sometimes come with a go-live license, as VC++ 2012 beta did this year for example.
- Don't assume "next release of VC++" means the historical "wait two years for the feature to appear in a product." As generally announced, Visual Studio is moving to faster update cycles, which means you should NOT expect to wait the historically-usual two years for these features to appear in a product release. (Though note that we haven't announced any release dates yet for VC++ vNext.)
- As I said in my November talk, we promised to share more conformance news in first half of 2013.
Whether to support the CTP releases in Boost.Config is still an open question. -- Eric Niebler BoostPro Computing http://www.boostpro.com