> (I realise there's always the option of adding a
> dummy reference, but I'm looking for a cleaner solution).

Is it really "unclean" ?

Suppose you'd like to use ocamldoc to output a dot file to understand
the dependencies of your program, if you manage to achieve what you
want to do you'll miss that dependency.

The more info there is in the source (vs. the build procedure) the
easier it is to understand the program.

Best,

Daniel