FFI - closure, __stginit

[Ondrej Rypacek]

Hi,
I'm just trying the ffi - importing some Haskell function into C. I've got a 
module "HelloWorld" with an exported function "add". And I got this 
"undefined reference" error while linking:

	undefined reference to `HelloWorld_zdfadd_closure'

Can anybody please help me, what's wrong here?

A second problem is the __stginit... function. I've defined 
void __stginit_HelloWorld (void) {}
with an empty body. Is this o.k.? Or should I make ghc to generate it for me 
somehow?

Thanks a lot, Ondra