title: GPRbuild: File specific compiler switches
body: <p>Does <code>GPRbuild</code> support a configuration option or any other way to apply special compiler switches only to special files?</p>
  
  <p>That could be useful if <code>-gnatyXYZ</code> switches for strict syntax checks are used for most files in a project but some external / not project specific Ada files are not compliant with the enforced syntax checks.</p>