title: /usr/lib/x86_64-linux-gnu/libstdc++.so.6: version `GLIBCXX_3.4.21' not found required by TensorFlow
body: <p>I'm trying to deploy a <strong>flask</strong> app on a <strong>debian</strong> server using Machine Learning libs, i managed that so far with most ML libraries but i got this error thanks to <strong>TensorFlow</strong> which i researched a lot about it with no working solution for me.</p>
  
  <p>PS : I'm using a 3.7 python venv for my app</p>
  
  <blockquote>
    <p>ImportError: /usr/lib/x86_64-linux-gnu/libstdc++.so.6: version `GLIBCXX_3.4.21' not found (required by /flask/wstest/lib/python3.7/site-packages/tensorflow/python/_pywrap_tensorflow_internal.so)
    Mar 01 15:32:11 django gunicorn[8803]: Failed to load the native TensorFlow runtime. </p>
  </blockquote>
  
  <p>I'm clearly missing the GLIBCXX <strong>3.4.21</strong> because <code>strings /usr/lib/x86_64-linux-gnu/libstdc++.so.6 | grep GLIBCXX</code>shows <strong>3.4.20</strong> as the latest version.</p>
  
  <p>Tried this fix <code>add-apt-repository ppa:ubuntu-toolchain-r/test</code>
  Gives this : 
  <a href="https://i.stack.imgur.com/tZR1u.png" rel="noreferrer">result of the toolchain add attempt</a></p>
  
  <p>Tried apt-get update, Got this </p>
  
  <blockquote>
    <p>W: Failed to fetch <a href="http://ppa.launchpad.net/ubuntu-toolchain-r/test/ubuntu/dists/jessie/main/binary-amd64/Packages" rel="noreferrer">http://ppa.launchpad.net/ubuntu-toolchain-r/test/ubuntu/dists/jessie/main/binary-amd64/Packages</a>  404  Not Found </p>
  </blockquote>
  
  <p>Also tried to update libgcc and libstdc++6, says i have the latest version.</p>
  
  <p>EDIT : I'm suspecting that Debian 8 Jessie doesn't support a higher glibcxx version than the 3.4.20.</p>