Make ghc-6.10 use a non-executable stack (by bumping libffi)

[kolmodin]

Attached patch:

Mon Mar 23 08:08:32 CET 2009  Lennart Kolmodin <kolmodin@gentoo.org>
  * Replace libffi 3.0.4 with libffi 3.0.8
  Use the latest version of libffi, which compiles with a non-executable
  stack. libffi 3.0.4 was the single piece of ghc using the executable stack,
  forcing the whole toolchain to use executable stacks (including all
  executables it compiled).

[kolmodin]

Due to attachment size limitations, I've put the patch here:  http://haskell.org/~kolmodin/replace-libffi-3_0_4-with-libffi-3_0_8.dpatch

[duncan]

Just to note that several distros (including Gentoo) consider executable stacks an important QA issue.

[simonmar]

I pushed this to the 6.10 branch (it wouldn't apply to HEAD for me, made darcs crash). Ian, could you merge to HEAD please?

[igloo]

Worked fine for me; perhaps your 6.10 repo is partial.

But HEAD had already updated to 3.0.6, so this conflicted. Also, HEAD has patches that get applied to libffi, which will need updating. Let's just do this update in the new build system.

[igloo]

The HEAD now has 3.0.8 too.