from ross

  buildGHC: reset search path before adding hs-source-dirs, so that these
  are the only directories GHC searches.

Distribution/Simple/Build.hs

@@ -281,6 +281,7 @@ constructGHCCmdLine comp srcLocs bi deps =
             then ["-hide-all-packages"]
             else [])
      ++ ["--make"]
+     ++ ["-i"]
      ++ ["-i" ++ l | l <- nub (hsSourceDirs bi ++ srcLocs)]
      ++ [ "-#include \"" ++ inc ++ "\"" | inc <- includes bi ]
      ++ nub (flags ++ hcOptions GHC (options bi))

package.conf.in

@@ -43,7 +43,7 @@ library-dirs:	LIB_DIR
 hs-libraries:   "HSCabal"
 extra-libraries:
 #if defined(mingw32_HOST_OS) || defined(__MINGW32__) || defined(_MSC_VER)
-	     "shell32"
+	     "shfolder"
 #endif
 
 include-dirs: