Fix warnings on non-Windows

compiler/coreSyn/CoreUtils.lhs

@@ -1521,7 +1521,7 @@ rhsIsStatic :: PackageId -> CoreExpr -> Bool
 -- When opt_RuntimeTypes is on, we keep type lambdas and treat
 -- them as making the RHS re-entrant (non-updatable).
 
-rhsIsStatic this_pkg rhs = is_static False rhs
+rhsIsStatic _this_pkg rhs = is_static False rhs
   where
   is_static :: Bool	-- True <=> in a constructor argument; must be atomic
   	  -> CoreExpr -> Bool
@@ -1549,7 +1549,7 @@ rhsIsStatic this_pkg rhs = is_static False rhs
    where
     go (Var f) n_val_args
 #if mingw32_TARGET_OS
-        | not (isDllName this_pkg (idName f))
+        | not (isDllName _this_pkg (idName f))
 #endif
 	=  saturated_data_con f n_val_args
 	|| (in_arg && n_val_args == 0)	

compiler/main/DynFlags.hs

@@ -88,9 +88,6 @@ import {-# SOURCE #-} ErrUtils ( Severity(..), Message, mkLocMessage )
 import Data.IORef	( readIORef )
 import Control.Exception ( throwDyn )
 import Control.Monad	( when )
-#ifndef mingw32_TARGET_OS
-import Util		( split )
-#endif
 
 import Data.Char
 import System.FilePath
@@ -1670,7 +1667,7 @@ setOptHpcDir arg  = upd $ \ d -> d{hpcDir = arg}
 
 machdepCCOpts :: DynFlags -> ([String], -- flags for all C compilations
 			      [String]) -- for registerised HC compilations
-machdepCCOpts dflags
+machdepCCOpts _dflags
 #if alpha_TARGET_ARCH
 	=       ( ["-w", "-mieee"
 #ifdef HAVE_THREADED_RTS_SUPPORT
@@ -1703,7 +1700,7 @@ machdepCCOpts dflags
       --
       -- -fomit-frame-pointer : *must* in .hc files; because we're stealing
       --   the fp (%ebp) for our register maps.
-	=  let n_regs = stolen_x86_regs dflags
+	=  let n_regs = stolen_x86_regs _dflags
 	       sta = opt_Static
 	   in
 	            ( [ if sta then "-DDONT_WANT_WIN32_DLL_SUPPORT" else ""