[BUG]: cuda::std::nullopt is undefined in device code

[trxcllnt]

Is this a duplicate?

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Type of Bug

Compile-time Error

Component

libcu++

Describe the bug

Attempting to construct a cuda::std::pair that contains a cuda::std::nullopt fails to compile.

#include <cuda/std/optional>

#include <thrust/for_each.h>
#include <thrust/execution_policy.h>

using cuda::std::pair;
using cuda::std::nullopt;
using cuda::std::optional;

__global__ void test(int* x, pair<int, optional<int>>* y) {
  thrust::for_each(thrust::seq, x, x+1, [&](auto const& i) {
    y[i] = {i, nullopt};
  });
}

int main(void) {
  test<<<1, 1, 1>>>(nullptr, nullptr);
}

$ nvcc -c /tmp/test_nullopt.cu -o /tmp/test_nullopt.cu.o
/tmp/test_nullopt.cu(11): error: identifier "cuda::std::__4::nullopt" is undefined in device code

How to Reproduce

0. See error in godbolt link.
1. Construct a cuda::std::pair that contains a cuda::std::nullopt in a device lambda

Expected behavior

The code works

Reproduction link

https://godbolt.org/z/K7q3KcaP9

Operating System

No response

nvidia-smi output

No response

NVCC version

No response