Adapt to work with GHC 6.12

- Adapted the package to work with GHC 6.12
- Plugins that depend on the old base3 are currently
  not correctly loaded as the plugin loaded misses
  the dependence on syb (leading to unresolved symbols)
- Cleaned up most of the testsuite (there are still
  some outstanding failures, of which only one
  demonstrates a bug in the plugins library as far
  as I can see — see previous bullet point)
- Cleaned out a little cruft (but more could be done)

src/System/Eval/Haskell.hs

@@ -51,11 +51,11 @@ import System.Plugins.Load
 import Data.Dynamic             ( Dynamic )
 import Data.Typeable            ( Typeable )
 
-import Data.Either
+import Data.Either              ( )
 import Data.Map as Map
 import Data.Char
 
-import System.IO
+import System.IO                ( )
 import System.Directory
 import System.Random
 import System.IO.Unsafe
@@ -122,7 +122,7 @@ eval_ src mods args ldflags incs = do
     pwd                <- getCurrentDirectory
     (cmdline,loadpath) <- getPaths      -- find path to altdata
     tmpf               <- mkUniqueWith dynwrap src mods
-    status             <- make tmpf $ ["-Onot"] ++ cmdline ++ args
+    status             <- make tmpf $ ["-O0"] ++ cmdline ++ args
     m_rsrc <- case status of
         MakeSuccess _ obj -> do
            m_v <- dynload obj (pwd:incs) (loadpath++ldflags) symbol

src/System/Eval/Utils.hs

@@ -71,7 +71,7 @@ escape s = concatMap (\c -> showLitChar c $ "") s
 --
 getPaths :: IO ([String],[String])
 getPaths = do
-        let make_line = ["-Onot","-fglasgow-exts","-package","plugins"]
+        let make_line = ["-O0","-fglasgow-exts","-package","plugins"]
         return (make_line,[])
 
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