title: How to choose a compiler version in Automake?
body: <p>I have several compilers with the same name but of different versions or location.
  The <code>./configure</code> script seems to stop at the first it finds in <code>PATH</code>. How can I tell Automake to choose one of them according to a custom rule ? I already have a macro which can check the compiler version.</p>
  
  <p>I would like to avoid setting the path by hand (with the <code>FC</code> variable) as it can be cumbersome to type each time the whole path.</p>
  
  <p>In my case, several MPI wrapper compilers are located in different directories with the same name (and added to the <code>PATH</code> by the user). </p>
  
  <p>The idea would be to use something like <code>./configure --with-intel</code> to find and select the IntelMPI compiler. </p>