diff -ru orig/Gtk2HsSetup.hs new/Gtk2HsSetup.hs
--- orig/Gtk2HsSetup.hs	2013-10-28 08:36:50.283581635 +0100
+++ new/Gtk2HsSetup.hs	2013-10-28 08:36:50.000000000 +0100
@@ -1,4 +1,4 @@
-{-# LANGUAGE CPP #-}
+{-# LANGUAGE CPP, ViewPatterns #-}
 
 #ifndef CABAL_VERSION_CHECK
 #error This module has to be compiled via the Setup.hs program which generates the gtk2hs-macros.h file
@@ -29,7 +29,7 @@
                                                emptyBuildInfo, allBuildInfo,
                                                Library(..),
                                                libModules, hasLibs)
-import Distribution.Simple.LocalBuildInfo (LocalBuildInfo(..),
+import Distribution.Simple.LocalBuildInfo (LocalBuildInfo(withPackageDB, buildDir, localPkgDescr, installedPkgs, withPrograms),
                                            InstallDirs(..),
                                            componentPackageDeps,
                                            absoluteInstallDirs)
@@ -56,14 +56,26 @@
 import Distribution.Verbosity
 import Control.Monad (when, unless, filterM, liftM, forM, forM_)
 import Data.Maybe ( isJust, isNothing, fromMaybe, maybeToList )
-import Data.List (isPrefixOf, isSuffixOf, nub, minimumBy)
+import Data.List (isPrefixOf, isSuffixOf, nub, minimumBy, stripPrefix)
 import Data.Ord as Ord (comparing)
-import Data.Char (isAlpha)
+import Data.Char (isAlpha, isNumber)
 import qualified Data.Map as M
 import qualified Data.Set as S
+import qualified Distribution.Simple.LocalBuildInfo as LBI
 
 import Control.Applicative ((<$>))
 
+#if CABAL_VERSION_CHECK(1,17,0)
+import Distribution.Simple.Program.Find ( defaultProgramSearchPath )
+onDefaultSearchPath f a b = f a b defaultProgramSearchPath
+libraryConfig lbi = case [clbi | (LBI.CLibName, clbi, _) <- LBI.componentsConfigs lbi] of
+  [clbi] -> Just clbi
+  _ -> Nothing
+#else
+onDefaultSearchPath = id
+libraryConfig = LBI.libraryConfig
+#endif
+
 -- the name of the c2hs pre-compiled header file
 precompFile = "precompchs.bin"
 
@@ -100,7 +112,7 @@
 
 fixLibs :: [FilePath] -> [String] -> [String]
 fixLibs dlls = concatMap $ \ lib ->
-    case filter (("lib" ++ lib) `isPrefixOf`) dlls of
+    case filter (isLib lib) dlls of
                 dlls@(_:_) -> [dropExtension (pickDll dlls)]
                 _          -> if lib == "z" then [] else [lib]
   where
@@ -111,7 +123,12 @@
     -- Yes this is a hack but the proper solution is hard: we would need to
     -- parse the .a file and see which .dll file(s) it needed to link to.
     pickDll = minimumBy (Ord.comparing length)
-
+    isLib lib dll =
+        case stripPrefix ("lib"++lib) dll of
+            Just ('.':_)                -> True
+            Just ('-':n:_) | isNumber n -> True
+            _                           -> False
+        
 -- The following code is a big copy-and-paste job from the sources of
 -- Cabal 1.8 just to be able to fix a field in the package file. Yuck.
 
@@ -144,8 +161,8 @@
 register :: PackageDescription -> LocalBuildInfo
          -> RegisterFlags -- ^Install in the user's database?; verbose
          -> IO ()
-register pkg@PackageDescription { library       = Just lib  }
-         lbi@LocalBuildInfo     { libraryConfig = Just clbi } regFlags
+register pkg@(library       -> Just lib )
+         lbi@(libraryConfig -> Just clbi) regFlags
   = do
 
     installedPkgInfoRaw <- generateRegistrationInfo
@@ -237,6 +254,7 @@
     = nub $
       ["-I" ++ dir | dir <- PD.includeDirs bi]
    ++ [opt | opt@('-':c:_) <- PD.cppOptions bi ++ PD.ccOptions bi, c `elem` "DIU"]
+   ++ ["-D__GLASGOW_HASKELL__="++show __GLASGOW_HASKELL__]
 
 installCHI :: PackageDescription -- ^information from the .cabal file
         -> LocalBuildInfo -- ^information from the configure step
@@ -426,7 +444,7 @@
 checkGtk2hsBuildtools :: [Program] -> IO ()
 checkGtk2hsBuildtools programs = do
   programInfos <- mapM (\ prog -> do
-                         location <- programFindLocation prog normal
+                         location <- onDefaultSearchPath programFindLocation prog normal
                          return (programName prog, location)
                       ) programs
   let printError name = do
diff -ru orig/SetupWrapper.hs new/SetupWrapper.hs
--- orig/SetupWrapper.hs	2013-10-28 08:36:50.283581635 +0100
+++ new/SetupWrapper.hs	2013-10-28 08:36:50.000000000 +0100
@@ -29,6 +29,24 @@
 import Control.Monad
 
 
+-- moreRecentFile is implemented in Distribution.Simple.Utils, but only in
+-- Cabal >= 1.18. For backwards-compatibility, we implement a copy with a new
+-- name here. Some desirable alternate strategies don't work:
+-- * We can't use CPP to check which version of Cabal we're up against because
+--   this is the file that's generating the macros for doing that.
+-- * We can't use the name moreRecentFiles and use
+--   import D.S.U hiding (moreRecentFiles)
+--   because on old GHC's (and according to the Report) hiding a name that
+--   doesn't exist is an error.
+moreRecentFile' :: FilePath -> FilePath -> IO Bool
+moreRecentFile' a b = do
+  exists <- doesFileExist b
+  if not exists
+    then return True
+    else do tb <- getModificationTime b
+            ta <- getModificationTime a
+            return (ta > tb)
+
 setupWrapper :: FilePath -> IO ()
 setupWrapper setupHsFile = do
   args <- getArgs
@@ -91,8 +109,8 @@
     -- Currently this is GHC only. It should really be generalised.
     --
     compileSetupExecutable = do
-      setupHsNewer      <- setupHsFile      `moreRecentFile` setupProgFile
-      cabalVersionNewer <- setupVersionFile `moreRecentFile` setupProgFile
+      setupHsNewer      <- setupHsFile      `moreRecentFile'` setupProgFile
+      cabalVersionNewer <- setupVersionFile `moreRecentFile'` setupProgFile
       let outOfDate = setupHsNewer || cabalVersionNewer
       when outOfDate $ do
         debug verbosity "Setup script is out of date, compiling..."
@@ -144,12 +162,3 @@
                    Nothing Nothing Nothing
       exitCode <- waitForProcess process
       unless (exitCode == ExitSuccess) $ exitWith exitCode
-
-moreRecentFile :: FilePath -> FilePath -> IO Bool
-moreRecentFile a b = do
-  exists <- doesFileExist b
-  if not exists
-    then return True
-    else do tb <- getModificationTime b
-            ta <- getModificationTime a
-            return (ta > tb)