Provide C++ Library Fundamentals TS v2
MSVC++ 2017 doesn't provide the library fundamentals v2 header files as part of CRT. It would be super awesome if MSVC++ 2019 shipped with this implemented and would be a nice stepping stone on the road towards C++20.
As you can see, there's not much there, most of it should be straightforward and simple enough to implement. However, one feature, the std::experimental::source_location class, requires compiler support in the form of a new intrinsic or builtin to populate an instance of this class with the correct metadata at the point of construction. Having a working source_location class as a part of MSVC++ would be beneficial for anyone working on C++ error handling and/or logging code where we currently have to use lots of preprocessor macros to capture and propagate __LINE__, __FILE__ and/or __FUNC__. source_location would also be very useful for the std::error/status_code proposal tentatively slated for C++23, or to be used by existing libraries such as Boost.Outcome.
You can see the rationale in one of the earlier proposals here: wg21.link/n4417