---
id: pr-cccl-cub-8967
repo: NVIDIA/cccl
pr: 8967
title: Also disable warpspeed scan below NVRTC 13.4
author: bernhardmgruber
date: '2026-05-13'
url: https://github.com/NVIDIA/cccl/pull/8967
source_category: upstream-code
architectures:
- sm100
tags:
- block
- scan
- warp
techniques:
- warp-specialization
hardware_features: []
kernel_types:
- scan
languages: []
captured_at: '2026-05-16'
status: merged
merge_sha: 1e20e1670125f02cf9fed55875c2ecdbc157685c
inclusion_reason: Search-matched CUDA kernel optimization PR; materialize diff/source before synthesis.
changed_paths:
- cub/cub/device/dispatch/tuning/tuning_scan.cuh
artifact_dir: evidence/pull-bundles/cccl-cub/gh-8967
head_ref_oid: 7d7d6dabdabb145d20e538afd60316d4d06c4132
---
# Also disable warpspeed scan below NVRTC 13.4

- Repository: `NVIDIA/cccl`
- PR: [8967](https://github.com/NVIDIA/cccl/pull/8967)
- 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/tuning/tuning_scan.cuh`

## Evidence Bundle

`evidence/pull-bundles/cccl-cub/gh-8967`
