title: Where is the CUDA toolkit located on Ubuntu?
body: <p>I installed Nvidia's 375 driver and CUDA 8.0 on Ubuntu 16.04 from <a href="https://developer.nvidia.com/cuda-80-ga2-download-archive" rel="nofollow noreferrer">Nvidia's .deb package</a>. I want to build TensorFlow with GPU support. This is the output of TensorFlow's <code>configure</code> script:</p>
  
  <pre class="lang-none prettyprint-override"><code>./configure                                                                            
  You have bazel 0.4.5 installed.
  Please specify the location of python. [Default is /usr/bin/python3]:
  Found possible Python library paths:
    /usr/local/lib/python3.5/dist-packages
    /usr/lib/python3/dist-packages
  Please input the desired Python library path to use.  Default is [/usr/local/lib/python3.5/dist-packages]
  
  Using python library path: /usr/local/lib/python3.5/dist-packages
  Do you wish to build TensorFlow with MKL support? [y/N]
  No MKL support will be enabled for TensorFlow
  Please specify optimization flags to use during compilation when bazel option "--config=opt" is specified [Default is -march=native]:
  Do you wish to use jemalloc as the malloc implementation? [Y/n]
  jemalloc enabled
  Do you wish to build TensorFlow with Google Cloud Platform support? [y/N]
  No Google Cloud Platform support will be enabled for TensorFlow
  Do you wish to build TensorFlow with Hadoop File System support? [y/N] y
  Hadoop File System support will be enabled for TensorFlow
  Do you wish to build TensorFlow with the XLA just-in-time compiler (experimental)? [y/N]
  No XLA support will be enabled for TensorFlow
  Do you wish to build TensorFlow with VERBS support? [y/N]
  No VERBS support will be enabled for TensorFlow
  Do you wish to build TensorFlow with OpenCL support? [y/N]
  No OpenCL support will be enabled for TensorFlow
  Do you wish to build TensorFlow with CUDA support? [y/N] y
  CUDA support will be enabled for TensorFlow
  Do you want to use clang as CUDA compiler? [y/N]
  nvcc will be used as CUDA compiler
  Please specify the CUDA SDK version you want to use, e.g. 7.0. [Leave empty to default to CUDA 8.0]:
  Please specify the location where CUDA 8.0 toolkit is installed. Refer to README.md for more details. [Default is /usr/local/cuda]:
  Invalid path to CUDA 8.0 toolkit. /usr/local/cuda/lib64/libcudart.so.8.0 cannot be found
  Please specify the CUDA SDK version you want to use, e.g. 7.0. [Leave empty to default to CUDA 8.0]:
  </code></pre>
  
  <p>The CUDA toolkit directory is not found at the default path, and I can't find it anywhere in <code>/usr</code>:</p>
  
  <pre class="lang-none prettyprint-override"><code>find /usr -type f -name '*cuda*'                                                       
  /usr/src/linux-headers-4.4.0-151/include/linux/cuda.h
  /usr/src/linux-headers-4.4.0-151/include/uapi/linux/cuda.h
  /usr/src/linux-headers-4.4.0-142/include/linux/cuda.h
  /usr/src/linux-headers-4.4.0-142/include/uapi/linux/cuda.h
  /usr/lib/nvidia-384/bin/nvidia-cuda-mps-server
  /usr/lib/nvidia-384/bin/nvidia-cuda-mps-control
  /usr/lib/x86_64-linux-gnu/libicudata.so.55.1
  /usr/share/man/man1/alt-nvidia-384-cuda-mps-control.1.gz
  /usr/share/vim/vim74/syntax/cuda.vim
  /usr/share/vim/vim74/indent/cuda.vim
  /usr/include/linux/cuda.h
  </code></pre>
  
  <p>Did I miss something in the CUDA installation?</p>