Binding for struct that has pointer

[DoHoonKim8]

Hello, I am using this great library for my work and really appreciate to the author in advance.

I have encountered a problem recently when initializing the struct(that is generated by bindgen) that has pointer as fields in Rust side. For clarity, let's assume the following C structs(that are both binding types).

struct Bar {};

struct Foo {
   struct Bar* bar
};

bindgen would generate the following Rust structs.

#[repr(C)]
pub struct Bar {}

#[repr(C)]
pub struct Foo {
    pub bar: *mut Bar,
}

So now I tried to create Foo struct from Rust side and then pass to CUDA.
So I did the following step,

1. malloc bar field and obtained CudaSlice<Bar>
2. and tried to initialize Foo with *mut Bar but I realized the pointer value field is private in CudaSlice

I was thinking about how to overcome this issue, and just tried to add one additional method that interprets pointer value to raw pointer *T in Rust like below.

impl<T> CudaSlice<T> {
    ...

    pub fn cast_to_ptr(&self) -> *const T {
        self.cu_device_ptr as *const T
    }
}

This code seems a bit awkward, because the returned raw pointer actually does not point to T in host memory(it points to the device memory). So, I'm not sure whether this approach makes sense. Is there any other way to overcome this? @coreylowman