LLVM 4.0.0
LLVM Coroutines - This is the most exciting thing for me. Gor Nishanov in his videos explains how coroutines are implemented and how are optimized by LLVM. Asynchronous IO code will be so easy to write and so efficient. 
Context switch in cost of function call, you can have billions of those coroutines, heap allocation elision (in certain cases). Can&#x27;t wait for coroutines to land in Clang.<p>I am a big fan of Go gorutines so Networking TS and Coroutines TS made me very happy, connecting both and having it in standard will be great. Just a shame that for Networking TS integration we will need to wait for C++20.