指定CUDAToolkit_INCLUDE_DIR等变量无效，CMake无法找到CUDA组件

问题重现 #

我的CMakeLists.txt内容如下：

cmake_minimum_required(VERSION 3.17)
project(ProjectName)
find_package(CUDAToolkit)

执行cmake ..时出现报错：

$ cmake .. 
-- Unable to find cuda_runtime.h in "/usr/share/cuda/include" for CUDAToolkit_INCLUDE_DIR.
-- Unable to find cudart library.
-- Could NOT find CUDAToolkit (missing: CUDA_CUDART) (found version "12.2.91")
-- Configuring done (0.0s)
-- Generating done (0.0s)
-- Build files have been written to: /home/Geremia/Downloads

手动指定包含cuda_runtime.h的正确目录/usr/share/cuda/targets/x86_64-linux/include后，CMake仍未搜索该目录，报错相同：

$ cmake .. -DCUDAToolkit_INCLUDE_DIR=/usr/share/cuda/targets/x86_64-linux/include
-- Unable to find cuda_runtime.h in "/usr/share/cuda/include" for CUDAToolkit_INCLUDE_DIR.
-- Unable to find cudart library.
-- Could NOT find CUDAToolkit (missing: CUDA_CUDART) (found version "12.2.91")
-- Configuring done (0.0s)
-- Generating done (0.0s)
-- Build files have been written to: /home/Geremia/Downloads

指定CUDAToolkit_ROOT变量也无效果。

解决方案 #

• 创建标准路径软链接：CUDA默认依赖/usr/local/cuda作为标准查找路径，若你的CUDA安装在/usr/share/cuda，手动创建软链接：

  sudo ln -s /usr/share/cuda /usr/local/cuda
  

  之后重新运行CMake即可。

• 同时指定头文件与库文件路径：单独指定CUDAToolkit_INCLUDE_DIR可能无效，需同时指定库目录（假设cudart库在/usr/share/cuda/targets/x86_64-linux/lib）：

  cmake .. -DCUDAToolkit_INCLUDE_DIR=/usr/share/cuda/targets/x86_64-linux/include -DCUDAToolkit_LIBRARY_DIR=/usr/share/cuda/targets/x86_64-linux/lib
  

• 直接指定cudart库路径：跳过目录查找，直接给CMake指定库文件位置：

  cmake .. -DCUDA_CUDART_LIBRARY=/usr/share/cuda/targets/x86_64-linux/lib/libcudart.so
  

• 升级CMake版本：CMake 3.17对CUDA 12.x的支持不完善，升级到3.20及以上版本，新版优化了CUDAToolkit的查找逻辑，适配非标准安装路径。

• 在CMakeLists.txt中硬编码路径：避免每次执行cmake传参，修改配置文件：

  cmake_minimum_required(VERSION 3.17)
  project(ProjectName)
  set(CUDAToolkit_INCLUDE_DIR "/usr/share/cuda/targets/x86_64-linux/include")
  set(CUDAToolkit_LIBRARY_DIR "/usr/share/cuda/targets/x86_64-linux/lib")
  find_package(CUDAToolkit REQUIRED)
  

内容的提问来源于stack exchange，提问作者Geremia