Is it possible to provide a LLVM independent build?

[Neutron3529]

I tried to publish another cuda crate without llvm or specific rust compiler support:

https://github.com/Neutron3529/cuda_min

Such crate works very well, and thus I have some doubt: why a specific llvm version and rust version is needed?

It seems that

1. llvm-bitcode-linker could compile rust code into PTX
2. nvidia driver could load PTX code directly. (no need to install cudart, nvidia's driver provides interfaces such as cuInit.)

I just wonder why a specific llvm version even a specific rustc version is required. We should have the ability to compile a cuda program easier.