---
id: pr-cccl-cub-8236
repo: NVIDIA/cccl
pr: 8236
title: Prevent ADL from finding user-namespace functions in `kernel_scan_warp`
author: viclafargue
date: '2026-04-01'
url: https://github.com/NVIDIA/cccl/pull/8236
source_category: upstream-code
architectures:
- sm100
tags:
- scan
- warp
techniques:
- warp-specialization
hardware_features: []
kernel_types:
- scan
languages:
- cuda-cpp
captured_at: '2026-05-16'
status: merged
merge_sha: 6e14d0499d34711e04eb01afbebeb8c0df4049cc
inclusion_reason: Search-matched CUDA kernel optimization PR; materialize diff/source before synthesis.
changed_paths:
- cub/cub/device/dispatch/kernels/kernel_scan_warpspeed.cuh
artifact_dir: evidence/pull-bundles/cccl-cub/gh-8236
head_ref_oid: c37e7cf8bc7c18a51873f20aaec42c2c6156ed9f
---
# Prevent ADL from finding user-namespace functions in `kernel_scan_warp`

- Repository: `NVIDIA/cccl`
- PR: [8236](https://github.com/NVIDIA/cccl/pull/8236)
- Decision: `Search-matched CUDA kernel optimization PR; materialize diff/source before synthesis.`
- Reason: Search-matched CUDA kernel optimization PR; materialize diff/source before synthesis.

## Changed Paths

- `cub/cub/device/dispatch/kernels/kernel_scan_warpspeed.cuh`

## Evidence Bundle

`evidence/pull-bundles/cccl-cub/gh-8236`
