[Haskell] Tracking custom dependencies with Cabal

[kyra]

My project contains some template-haskell generated C code.

I maintain both make- and cabal-based build systems for this project.

While tracking such a dependency in a make-based setting is pretty much 
trivial, I'm not aware of any "natural" Cabal facilities to accomplish 
this and now I'm using an ugly hack with compile time updated 
"extra-library". Am I missing something? How would you solve this problem?

Cheers,
Kyra