Reference variables in lambdas don't show the values in the watch window while debugging

[Saitama10000]

Reference variables in lambdas don't show the values in the watch window while debugging.

Example code:

#include <iostream>
#include "cooperative_groups.h"
namespace cg = cooperative_groups;

template <typename _value_type, int _size>
class Array
{
public:
    using value_type = _value_type;
    __device__ __host__ constexpr Array(std::initializer_list<_value_type> l) { int i = 0; for (auto x : l) (*this)[i++] = x; }
    __device__ __host__ constexpr auto operator[](int i) const { return data[i]; }
    __device__ __host__ constexpr auto operator[](int i) -> auto& { return data[i]; }
    __device__ __host__ constexpr auto size() const { return _size; }
private:
    value_type data[_size]{};
};

__global__ void kernel()
{
    // not showing values of arr, references don't work?
    auto iota = []<typename T, int size>(Array<T, size>& arr, T start)
    {
        for (int i = 0; i < arr.size(); i++)
            arr[i] = start++;
    };

    // showing values of arr
    auto iota2 = []<typename T, int size>(Array<T, size> arr, T start)
    {
        for (int i = 0; i < arr.size(); i++)
            arr[i] = start++;
        return arr;
    };

    Array<int, 8> arr{};
    iota(arr, 0);
    arr = iota2(arr, 0);
}

int main()
{

    kernel<<<1, 8>>>();
    cudaDeviceSynchronize();
}

I don't know if this is a bug, a known limitation or if I'm doing something wrong on my end.

[sanannavyaa]

What CTK version are you using?

[Saitama10000]

@sanannavyaa 12.0.1

[sanannavyaa]

This is a cuda-gdb bug, thanks for reporting it. We're working on it! I will make sure to update this issue when the bug has been fixed.