When modules use other modules those modules used by other modules should be translated first, but that doesn't happen unless the main program did so first.

[Tricky1975]

Program prog
use 
    mod1
end

module mod1
 use
      mod2
  end

This should cause mod2 to be translated first, but it is in fact translated after mod1 which can lead to very funny situations (parse errors most notably or spooked up translations which can (depending on the target language) be lethal).