Will older compute capabilities miss certain CUDA Driver API's ?


I’ve been wondering what happens on older graphics cards in regards to the CUDA Driver API.

Some functions have a conditional in front of them, I am not sure what it means:

#if __CUDA_API_VERSION >= 4000

What happens on older graphics cards ? Will these functions fail ? Will these functions not be present ?

What if users install new drivers, will these functions be available again ?

For example cuStreamDestroy has such a conditional…