A new beta version b31 is on its way from John Hansen. Quoting from Lugnet:

“…
The main new features are a safecall keyword and compiler switch which lets you call subroutines from multiple threads without having to manually wrap the call in Acquire & Release. If you mark a function as being a safecall function then the compiler will handle it automatically for you. And if you want all your functions to be called using the safecall convention then you can simply add the -safecall switch to the NBC command line.

Also new in NBC b31 as well as in BricxCC’s built-in version of b31 there is now support for the RICScript programming language which lets you create RIC files via a text-based script. There will be enhancements here that involve importing a sprite from an external file and things like that but for now it is at least fully functional and well integrated with the latest BricxCC test release. “