Also, since you want to clean your build, could you alternatively remove all files defined in .gitignore manually (reference code).

To many files there…
I am sure that I set a CUDA path, but can not find that
$ grep -ri cuda build
build/CMakeCache.txt://Statically link CUDA libraries
build/CMakeCache.txt:CAFFE2_STATIC_LINK_CUDA:BOOL=OFF
build/CMakeCache.txt://Use CUDA
build/CMakeCache.txt:USE_CUDA:BOOL=True
build/CMakeCache.txt://Use NVRTC. Only available if USE_CUDA is on.

Am I looking into the right folder?