Also folks should check out or comprehensive release notes: https://www.visualstudio.com/en-us/news/releasenotes/vs2017-...
Sadly no mention of any improvements to their C compiler :( The C99 support is still incomplete and it looks like MS has given up on C.
For anyone else that still wants to write straight C, there are other compilers and Microsoft has integrated clang's frontend with VC++ backend.
This has already been communicated in a few places.
Cloudfare's crash just proved once more why the world needs less C.