That, along with your HSrts.o later, ties in with the files that change file size except that /usr/lib/ghc-6.0/package.conf gains a "pthread" in the rts extra libraries.
Ah yes, I overlooked that, because it doesn't happen on Mac OS X :-).
It looks like I want to make a package-threaded.conf that thinks the rts package is 'hs_libraries = ["HSrts-threaded"],' which I install into the same directory [...]
Something like that, I guess.
As for the .hi files... no idea why they should be different, the configure flag absolutely positively doesn't affect how the libraries are built - do the hi files perhaps contain a timestamp or something else that might change on its own?
Could be - looking at one of the .a files at random (libHSposix.a) it looks like it is the timestamps of the files inside it that has changed.
FWIW the .hi differences on /usr/lib/ghc-6.0/imports/GHC/Int.hi are: (again chosen at random) (note that these are not contiguous)
I don't see anything here.
One more thing - is there an easy way to check to see if it has worked? I assume a Haskell program can't tell whether or not it is being run in a threaded-rts? I have access to a dual-CPU machine so I can time things with and without if that makes sense.
Dual-CPU doesn't help, as the threaded RTS still only runs one Haskell thread at a time (SMP is a lot harder). However, import Foreign foreign import ccall sleep :: Int -> IO () -- slightly wrong signature, but still works :-) main = do forkIO $ sequence_ $ repeat $ putStrLn "Hello, world." sleep 10 If the above program prints "Hello, world." like mad for 10 seconds, it's the threaded RTS; if it prints it at most a few times and then stops for 10 seconds, it's the non-threaded RTS. Hope that helps, Cheers, Wolfgang