title: Switching GCC version to use on macbook M1
body: <p>I received this error when I tried to compile by gcc 11.x and run some code on my Macbook Pro M1</p>
  <p><code>E  ImportError: dlopen(/Users/giangpham/VSCode/rpxdock/rpxdock/bvh/bvh.cpython-37m-darwin.so, 0x0006): tried: ‘/Users/giangpham/VSCode/rpxdock/rpxdock/bvh/bvh.cpython-37m-darwin.so’ (mach-o file, but is an incompatible architecture (have ‘arm64’, need ‘x86_64’))</code></p>
  <p>I tried to install another homebrew for x86_64 architecture and install the old gcc ver 9 (which is the version recorded to have worked with the code before) following <a href="https://medium.com/mkdir-awesome/how-to-install-x86-64-homebrew-packages-on-apple-m1-macbook-54ba295230f" rel="nofollow noreferrer">this article</a></p>
  <p>I have done <code>axbrew info gcc</code> and it would still give out information of the 11.x gcc (<code>axbrew info gcc@9</code> works and gives me info of the package. But I tried <code>switch`` as the article suggested and it saids </code>unknown command```). How do I switch gcc to use the older version I just installed?</p>
  <p>Thank you!</p>