[zepolen]

Real time programming requires you to be able to make hard guarantees about how long a certain piece of code can run and what resources it uses.

This is literally impossible with a GC because you can only bound one resource (time or memory) at a time.

The best RTS languages are a pain in the ass to use because the compiler will complain about every single thing - cases that could go wrong with your code

They are used in mission critical (in all sense of the word) systems like spaceships - where a tiny bit of lag will send it thousands of miles in the wrong direction.

Those links you provided, one is a draft for a spec, it's not even implemented yet - and the other has nothing to do with real time languages.