cuda: set cuda compiler path (#13527)

[lizhenneng]

We can set CMAKE_CUDA_COMPILER to /usr/local/cuda/bin/nvcc, but it's is not compatible with other system, so we use cmake's variable CUDAToolkit_NVCC_EXECUTABLE.

[CISC]

According to the docs:

CUDAToolkit_NVCC_EXECUTABLE
Note that this path may not be the same as CMAKE_CUDA_COMPILER

Which means you probably should not unconditionally override CMAKE_CUDA_COMPILER.

[lizhenneng]

According to the docs:

CUDAToolkit_NVCC_EXECUTABLE
Note that this path may not be the same as CMAKE_CUDA_COMPILER

Which means you probably should not unconditionally override CMAKE_CUDA_COMPILER.

I will revise my patch later。

[lizhenneng]

According to the docs:

CUDAToolkit_NVCC_EXECUTABLE
Note that this path may not be the same as CMAKE_CUDA_COMPILER

Which means you probably should not unconditionally override CMAKE_CUDA_COMPILER.

[lizhenneng]

Will you merge this patch?

[slaren]

I don't think there is enough justification to merge this. You can set manually CMAKE_CUDA_COMPILER if you have an unusual system configuration with multiple nvcc compilers.

[CISC]

I don't think there is enough justification to merge this. You can set manually CMAKE_CUDA_COMPILER if you have an unusual system configuration with multiple nvcc compilers.

And certainly not as-is, it still unconditionally overrides the variable.