title: Issues including Eigen for simple C++ TensorFlow Lite test program
body: <p>I compiled the library for the C++ API for TensorFlow Lite (r1.97) using the script <code>${TENSORFLOW_ROOT}/tensorflow/lite/tools/make/build_rpi_lib.sh</code> following the steps suggested at this official <a href="https://www.tensorflow.org/lite/rpi" rel="nofollow noreferrer">page</a> (Native Compiling, downloading the necessary libraries), where <code>${TENSORFLOW_ROOT}</code> is the root folder where I cloned the repository.</p>
  
  <p>I am trying to compile this simple <code>test.cpp</code> program:</p>
  
  <pre class="lang-cpp prettyprint-override"><code>#include &lt;memory&gt;
  
  #include "tensorflow/lite/interpreter.h"
  
  int main(void)
  {
      std::unique_ptr&lt;tflite::Interpreter&gt; interpreter(new tflite::Interpreter);
  }
  </code></pre>
  
  <p>using the command:</p>
  
  <pre><code>gcc-6 test.cpp -I${TENSORFLOW_ROOT} -I${TENSORFLOW_ROOT}/tensorflow/contrib/makefile/downloads/eigen -I${TENSORFLOW_ROOT}/tensorflow/contrib/makefile/downloads/protobuf/src -I${TENSORFLOW_ROOT}/tensorflow/contrib/makefile/downloads -L${TENSORFLOW_ROOT}/tensorflow/lite/tools/make/gen/rpi_armv7l/lib -lstdc++ -ldl -ltensorflow-lite
  </code></pre>
  
  <p>The list of includes was suggested in the <a href="https://www.tensorflow.org/lite/tfmobile/linking_libs" rel="nofollow noreferrer">Integrating TensorFlow libraries</a> page (specifically from the section iOS). Compilation fails with the following error related to the inclusion of Eigen:</p>
  
  <pre><code>${TENSORFLOW_ROOT}/third_party/eigen3/unsupported/Eigen/CXX11/Tensor:1:42: fatal error: unsupported/Eigen/CXX11/Tensor: No such file or directory
   #include "unsupported/Eigen/CXX11/Tensor"
  </code></pre>
  
  <p>I found several links where an apparently similar problem is discussed (such as this <a href="https://stackoverflow.com/questions/46731174/unsupported-eigen-cxx11-tensor-no-such-file-or-directory-while-working-with-t?rq=1">one</a>), but the proposed solutions involve using references to the TensorFlow python package which is something that is not possible in my case (and it feels quite patchy - I am not considering using python for this project).</p>
  
  <p>I also tried using a different include path to Eigen (e.g. <code>${TENSORFLOW_ROOT}/third_party/eigen3</code>):</p>
  
  <pre><code>gcc-6 test.cpp -I${TENSORFLOW_ROOT} -I${TENSORFLOW_ROOT}/third_party/eigen3 -I${TENSORFLOW_ROOT}/tensorflow/contrib/makefile/downloads/protobuf/src -I${TENSORFLOW_ROOT}/tensorflow/contrib/makefile/downloads -L${TENSORFLOW_ROOT}/tensorflow/lite/tools/make/gen/rpi_armv7l/lib -lstdc++ -ldl -ltensorflow-lite
  </code></pre>
  
  <p>and also this causes Eigen related compilation errors of this sort:</p>
  
  <pre><code>...
  ${TENSORFLOW_ROOT}/third_party/eigen3/unsupported/Eigen/CXX11/Tensor:1:42: error: #include nested too deeply
   #include "unsupported/Eigen/CXX11/Tensor"
  ...
  ${TENSORFLOW_ROOT}/third_party/eigen3/Eigen/Core:1:22: error: #include nested too deeply
   #include "Eigen/Core"
  ...
  </code></pre>
  
  <p>Any suggestions on how to solve this issue? What is the right set of include paths?</p>