Profiling makes FFI Marshalling of Doubles and Int64s fail

[Bayley, Alistair]

I've built a small test case. When I compile with:
  ghc Main.hs test.c -o Main.exe

... the (correct) output from Main.exe is:
123.0
5678901234567890

And when I compile with:
  ghc -prof Main.hs test.c -o Main.exe

... the (incorrect) output from Main.exe is:
1.0
986516178



------ Main.hs:
{-# OPTIONS -ffi #-}
module Main where
import Foreign.C
foreign import ccall "myDouble" myDouble :: IO CDouble
foreign import ccall "myInt64" myInt64 :: IO CLLong
main = do
  d <- myDouble
  putStrLn $ show d
  l <- myInt64
  putStrLn $ show l


------ test.c:
double myDouble() {
	double d = 123.0;
	return d;
}
long long myInt64() {
	long long x = 5678901234567890;
	return x;
}

-----------------------------------------
*****************************************************************
Confidentiality Note: The information contained in this 
message, and any attachments, may contain confidential 
and/or privileged material. It is intended solely for the 
person(s) or entity to which it is addressed. Any review, 
retransmission, dissemination, or taking of any action in 
reliance upon this information by persons or entities other 
than the intended recipient(s) is prohibited. If you received
this in error, please contact the sender and delete the 
material from any computer.
*****************************************************************