My opinion: If you can't use Haskell, you should definitely use a null-free language for safety in this day and age, which means Rust and definitely not C/C++.
As always, pragmatism is good. If you are good at C/C++, use it and be happy and productive. I presumed the context of this discussion, however, was wanting to use Haskell for its particular benefits, and in my opinion the null-free nature is a key benefit, which would not be achieved by using C/C++.
I want to eventually use it, but not at the price of my productivity.