title: gcc : permission denied after new installion
body: <p>It's a new installation on <strong>Deepin OS</strong>. I wanted to install <strong>gcc-8.3.0</strong> on my computer.</p>
  
  <p>I've done this manually cause it only propose me gcc-6 with apt. So I've installed all the depedency (GMP, MPFR, MPC, isl...) then I've proceeded to gcc. I've followed this tutorial : <a href="https://archerfmy.github.io/2017/04/12/How-to-switch-your-gcc-g-version-in-ubuntu/" rel="nofollow noreferrer">https://archerfmy.github.io/2017/04/12/How-to-switch-your-gcc-g-version-in-ubuntu/</a> to add the new installation. But now the problem is that I can't use gcc anymore.</p>
  
  <hr>
  
  <pre><code>gcc 
  zsh: permission denied: gcc
  </code></pre>
  
  <hr>
  
  <pre><code>which -a gcc
  gcc not found
  </code></pre>