I have built an unregistered LLVM cross-compiler for arm-unknown-nto-qnx8.0.0eabi, which I finally got to build using the attached patch. Simple programs no longer crash like they do in registered ARM cross-compilers (as reported on mailing list at http://www.haskell.org/pipermail/ghc-devs/2013-January/000005.html and other places), however the following code does crash:

{-# LANGUAGE ForeignFunctionInterface #-}
module Main (main) where

import Foreign.Ptr

foreign import ccall "wrapper" wrap_refresh :: ( IO ()) -> IO (FunPtr ( IO ()))

main :: IO ()
main = do
	wrap_refresh (return ())
	return ()

It seems, from experiments, that any code using the "wrapper" imports causes this error:

$ ./Main
*** stack smashing detected ***: Main terminated
Abort (core dumped)