[BUG]: thrust::pair is not trivially copyable in CCCL branch/2.3.x

[bdice]

Is this a duplicate?

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Type of Bug

Compile-time Error

Component

Thrust

Describe the bug

The thrust::pair class was trivially copyable in CCCL 2.2.0 but is not trivially copyable in branch/2.3.x. I suspect #262 is the PR that introduced this change (bug?).

This leads to compilation failures in RAPIDS cuDF because RMM requires rmm::device_uvector to use trivially copyable types. For example: https://github.com/rapidsai/cudf/actions/runs/7403019153/job/20142041800?pr=14704#step:8:1714

/home/coder/.conda/envs/rapids/include/rmm/device_uvector.hpp(78): error: static assertion failed with "device_uvector only supports types that are trivially copyable."
          detected during instantiation of class "rmm::device_uvector<T> [with T=cuda::std::__4::pair<std::size_t, std::size_t>]" 
/home/coder/cudf/cpp/src/copying/contiguous_split.cu(1412): here

How to Reproduce

Switch between CCCL 2.2.0 and trunk. 2.2.0 passes, but trunk fails.
https://godbolt.org/z/oeEKa5577

Also see rapidsai/cudf#14704

Expected behavior

thrust::pair behavior should not change (it should be trivially copyable in CCCL trunk).

Reproduction link

https://godbolt.org/z/oeEKa5577

Operating System

No response

nvidia-smi output

No response

NVCC version

No response