showBool False = "NO"

     platform  = targetPlatform dflags

     isWindows = platformOS platform == OSMinGW32

     expandDirectories :: FilePath -> Maybe FilePath -> String -> String

 -- Note [Special unit-ids]

 -- ~~~~~~~~~~~~~~~~~~~~~~~

   , sMergeObjsSupportsResponseFiles

   , sLdIsGnuLd

   , sGccSupportsNoPie

   , sArSupportsDashL

   , sPgm_L

   , sPgm_P

   , toolSettings_mergeObjsSupportsResponseFiles :: Bool

   , toolSettings_ldIsGnuLd               :: Bool

   , toolSettings_ccSupportsNoPie         :: Bool

   , toolSettings_arSupportsDashL         :: Bool

   , toolSettings_cmmCppSupportsG0        :: Bool

 sLdIsGnuLd = toolSettings_ldIsGnuLd . sToolSettings

 sGccSupportsNoPie :: Settings -> Bool

 sGccSupportsNoPie = toolSettings_ccSupportsNoPie . sToolSettings

 sArSupportsDashL :: Settings -> Bool

 sArSupportsDashL = toolSettings_arSupportsDashL . sToolSettings

       getBooleanSetting key = either pgmError pure $

         getRawBooleanSetting settingsFile mySettings key

   -- see Note [topdir: How GHC finds its files]

   -- NB: top_dir is assumed to be in standard Unix

   -- format, '/' separated

         -- see Note [tooldir: How GHC finds mingw on Windows]

   let getSetting_raw key = either pgmError pure $

       getSetting_topDir top key = either pgmError pure $

         getRawFilePathSetting top settingsFile mySettings key

       getSetting_toolDir top tool key =

       getSetting key = getSetting_topDir top_dir key

       getToolSetting key = getSetting_toolDir top_dir mtool_dir key

       getToolPath :: (Target -> Program) -> String

       getToolPath key = expandDirVars top_dir mtool_dir (prgPath . key $ target)

       , toolSettings_mergeObjsSupportsResponseFiles

                                       = maybe False mergeObjsSupportsResponseFiles

                                                          $ tgtMergeObjs target

       , toolSettings_arSupportsDashL  = arSupportsDashL  $ tgtAr target

       , toolSettings_cmmCppSupportsG0 = cmmCppSupportsG0 $ tgtCmmCPreprocessor target

 -- | Expand occurrences of the @$tooldir@ interpolation in a string

 -- on Windows, leave the string untouched otherwise.

 expandToolDir

   -> String -> String

 #if defined(mingw32_HOST_OS)

 #else

 #endif

 -- | Returns a Unix-format path pointing to TopDir.

 -- Returns @Nothing@ when not on Windows.

 -- When called on Windows, it either throws an error when the

 -- tooldir can't be located, or returns @Just tooldirpath@.

 findToolDir

   -> IO (Maybe FilePath)

 #if defined(mingw32_HOST_OS)

   where maxDepth = 3

         go :: Int -> FilePath -> [FilePath] -> IO (Maybe FilePath)

         go k path tried

               if oneLevel

                 then return (Just path)

                 else go (k+1) (path </> "..") tried'

 #else

 #endif

   [FP_CAPITALIZE_YES_NO(["$enableval"], [EnableDistroToolchain])],

   [EnableDistroToolchain=NO]

 )

 if test "$EnableDistroToolchain" = "YES"; then

   TarballsAutodownload=NO

 dnl ** Check to see whether ln -s works

 AC_PROG_LN_S

 dnl ** Find the path to sed

 AC_PATH_PROGS(SedCmd,gsed sed,sed)

   [FP_CAPITALIZE_YES_NO(["$enableval"], [EnableDistroToolchain])],

   [EnableDistroToolchain=@EnableDistroToolchain@]

 )

 if test "$HostOS" = "mingw32" -a "$EnableDistroToolchain" = "NO"; then

   FP_SETUP_WINDOWS_TOOLCHAIN([$hardtop/mingw/], [\$\$topdir/../mingw/])

 AC_SUBST(BaseUnitId)

 # We get caught by

 #     http://savannah.gnu.org/bugs/index.php?1516

 #     $(eval ...) inside conditionals causes errors

 VALIDATE_GHC_TOOLCHAIN([default.target],[default.target.ghc-toolchain])

 rm -Rf acargs acghc-toolchain actmp-ghc-toolchain

 echo "****************************************************"

 	@rm -f $@

 	@echo '[("target os", "$(HaskellTargetOs)")' >> $@

 	@echo ',("target arch", "$(HaskellTargetArch)")' >> $@

 	@echo ',("unlit command", "$$topdir/../bin/$(CrossCompilePrefix)unlit")' >> $@

 	@echo ',("target RTS linker only supports shared libraries", "$(TargetRTSLinkerOnlySupportsSharedLibs)")' >> $@

 	@echo ',("Use interpreter", "$(GhcWithInterpreter)")' >> $@

 	@echo ',("Support SMP", "$(GhcWithSMP)")' >> $@

 	@echo ',("base unit-id", "$(BaseUnitId)")' >> $@

 	@echo "]" >> $@

 # We need to install binaries relative to libraries.

 BINARIES = $(wildcard ./bin/*)

 .PHONY: install_bin_libdir

         installPrefix <- fromMaybe (error prefixErr) <$> cmdPrefix

         installTo NotRelocatable installPrefix

     phony "binary-dist-dir" $ do

         version        <- setting ProjectVersion

         targetPlatform <- setting TargetPlatformFull

         , ("target arch",      queryTarget (show . archOS_arch . tgtArchOs))

         , ("unlit command", ("$topdir/../bin/" <>) <$> expr (programName (ctx { Context.package = unlit })))

         , ("target has libm", expr $  lookupSystemConfig "target-has-libm")

         , ("target RTS linker only supports shared libraries", expr $ yesNo <$> targetRTSLinkerOnlySupportsSharedLibs)

         , ("Use interpreter", expr $ yesNo <$> ghcWithInterpreter (predStage stage))

         , ("Support SMP", expr $ yesNo <$> targetSupportsSMP)

 # $2 the location that the windows toolchain will be installed in relative to the libdir

 AC_DEFUN([FP_SETUP_WINDOWS_TOOLCHAIN],[

     # N.B. The parameters which get plopped in the `settings` file used by the

     # resulting compiler are computed in `FP_SETTINGS`. Specifically, we use

     # $$topdir-relative paths instead of fullpaths to the toolchain, by replacing

 dnl * FP_SETUP_WINDOWS_TOOLCHAIN will set the toolchain variables to paths

 dnl   to the bundled toolchain (e.g. CFLAGS=/full/path/to/mingw/bin/gcc)

 dnl

 dnl   mingw tooldir by $tooldir (see SUBST_TOOLDIR).

 dnl   The reason is the Settings* variants of toolchain variables are used by the bindist configure to

 dnl   create the settings file, which needs the windows bundled toolchain to be relative to $tooldir.

 dnl

 dnl The ghc-toolchain program isn't concerned with any of these complications:

 dnl it is passed either the full paths to the toolchain executables, or the bundled

 dnl mingw path is set first on $PATH before invoking it. And ghc-toolchain

 # SUBST_TOOLDIR

 # ----------------------------------

 #      inplace mingw, and update by substituting said occurrences by

 #      the value of $mingw_install_prefix, where the mingw toolchain will be at

 #      install time

 # See Note [How we configure the bundled windows toolchain]

 AC_DEFUN([SUBST_TOOLDIR],

 [

 ])

                    }

     return t