Subject: Re: [boost] Status of Visual Studio 2017 support
From: Stephan T. Lavavej (stl_at_[hidden])
Date: 2017-02-14 18:07:54
> the final release may be significantly different from the pre-released versions.
> It is not unheard of entire features being removed or modified in the final release.
Our process is that between Previews and RC, we enter "ask mode" (ask for permission to make changes), and between RC and RTM we enter "escrow mode", which is a very strict lockdown. The only bugs that are fixed in escrow mode are of the form "it's melting users' hard drives and the metal fumes are making people dizzy".
VS 2017 is a little different than before (in that we've intentionally had 4 release candidates so far, although not prominently branded as such), but we're definitely locked down now. A useful heuristic is that when we've publicly announced the release date for RTM, as we recently did (March 7), the time for major changes is long past.
The toolset (compiler/linker/libraries), which is what Boost is interested in, also locks down before the rest of the product, because we're at a low level in the stack. Throughout 10 years in Visual C++, I've taken several fixes through ask mode, but never through escrow mode that I can recall. We're focused on the next toolset update at the moment.
For Boost, the policy I would recommend is: treat Previews as unsupported (major feature changes in them), but attempt to support RC builds when they appear. This will lead to better synchronization between Boost and VS releases.