title: Rstudio gfortran flag -m64 doesn't work, but it does work on the than command line
body: <p>I am trying to run <a href="https://github.com/LAPKB/Pmetrics" rel="nofollow noreferrer">https://github.com/LAPKB/Pmetrics</a> on an M1 chip mac. One of the functions makes use of gfortran. When I run this function in Rstudio, I get the error</p>
  <pre><code>gfortran: error: unrecognized command-line option '-m64'
  </code></pre>
  <p>When I run the function from the command line with Rscript it runs correctly.</p>
  <p>How can I get Rstudio to work with gfortran option -m64?</p>