Problema del vinculador de tiempo de ejecución de GHCi al utilizar declaraciones FFI

Tengo un problema con respecto a FFI en Haskell y el modo interactivo de GHCotra vez.

ConsiderarFFISo.hs:

{-# LANGUAGE OverloadedStrings #-}
module Main where

import qualified Data.ByteString.Char8 as B

import FFIFun.Foo

main :: IO ()
main = do
  B.putStrLn "main"
  callMeFromC
  callMeFromHaskell
  return ()

c.c:

#include <stdio.h>

void callMeFromC(void);

void callMeFromHaskell(void)
{
    printf("callMeFromHaskell\n");
    callMeFromC();
}

FFIFun/Foo.hs:

{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE ForeignFunctionInterface #-}
module FFIFun.Foo where

import qualified Data.ByteString.Char8 as B

foreign import ccall "callMeFromHaskell"
  callMeFromHaskell :: IO ()

foreign export ccall callMeFromC :: IO ()
callMeFromC :: IO ()
callMeFromC = B.putStrLn "callMeFromC"

y unMakefile:

SHELL := bash

GHC_OPT := -Wall -O2 -fno-warn-unused-do-bind


all: ffiso

test: ffiso
    ./$<

ffiso: FFISo.hs c.c
    ghc --make $(GHC_OPT) $^ -o $@

clean:
    rm -rf *{.hi,o,_stub.*} ffiso FFIFun/*{.hi,.o,_stub.*}

ghci: ffiso
    ghci -package bytestring FFIFun/Foo.o c.o FFISo.hs

lo encuentras tambienaquí como una esencia.

Entonces, mi problema ahora:

$ make ghci
[...]
Ok, modules loaded: Main, FFIFun.Foo.
Prelude Main> -- fine, it's loading.
Prelude Main> :t callMeFromC

<interactive>:1:1: Not in scope: `callMeFromC'
Prelude Main> -- uhm, why?
Prelude Main> :t main
main :: IO ()
Prelude Main> main


GHCi runtime linker: fatal error: I found a duplicate definition for symbol
   FFIFunziFoo_callMeFromC_info
whilst processing object file
   ./FFIFun/Foo.o
This could be caused by:
   * Loading two different object files which export the same symbol
   * Specifying the same object file twice on the GHCi command line
   * An incorrect `package.conf' entry, causing some object to be
     loaded twice.
GHCi cannot safely continue in this situation.  Exiting now.  Sorry.

Hrmpf, ¿qué está mal aquí? Curiosamente me sale un error diferente eni686 (arriba, es unx86_64 sistema, pero ambos GHC 7.4.1):

GHCi runtime linker: fatal error: I found a duplicate definition for symbol
   __stginit_FFIFunziFoo
whilst processing object file
   ./FFIFun/Foo.o
This could be caused by:
   * Loading two different object files which export the same symbol
   * Specifying the same object file twice on the GHCi command line
   * An incorrect `package.conf' entry, causing some object to be
     loaded twice.
GHCi cannot safely continue in this situation.  Exiting now.  Sorry.

Además, ¿hay alguna documentación al respecto? Siento que soy el único que tiene dificultades con FFI y GHCi.

editar: nota, quemake test funciona bien:

$ ghc --make -Wall -O2 -fno-warn-unused-do-bind FFISo.hs c.c -o ffiso
[1 of 2] Compiling FFIFun.Foo       ( FFIFun/Foo.hs, FFIFun/Foo.o )
[2 of 2] Compiling Main             ( FFISo.hs, FFISo.o )
Linking ffiso ...
./ffiso
main
callMeFromC
callMeFromHaskell
callMeFromC