RefCountedArrays.jl provides a reference-counted array, the RCArray, which
uses malloc-backed memory and supports being freed eagerly with
RefCountedArrays.unsafe_free!, just like CUDA.jl and other GPU array types.
Unlike Julia's venerable Array, which is GC-managed and thus lazily
collected, the RCArray can be freed the moment that the user or library that
allocated it knows that it's no longer used. When used correctly, this feature
can allow for very tight control of memory, which is especially valuable for
library authors who know the "lifetime" of the arrays that their library
allocates.