title: How do I remove 1 char in makefile
body: <p>I want to remove a character of string in makefile, for example</p>
  
  <pre><code>FOO = 123-456-789-
  all:
    # want to display 123-456-789
    echo "$(FOO)"
  </code></pre>
  
  <p>I want to remove the last char in sting "-", which mean
  how to let "123-456-789-" become "123-456-789"</p>
  
  <p>thanks</p>