diff --git a/compiler/GHC/Driver/Session.hs b/compiler/GHC/Driver/Session.hs
index 1d77a19e7f67..5d15c8102532 100644
--- a/compiler/GHC/Driver/Session.hs
+++ b/compiler/GHC/Driver/Session.hs
@@ -278,7 +278,7 @@ import GHC.Core.Opt.CallerCC
 import GHC.Parser (parseIdentifier)
 import GHC.Parser.Lexer (mkParserOpts, initParserState, P(..), ParseResult(..))
 
-import GHC.SysTools.BaseDir ( expandToolDir, expandTopDir )
+import GHC.SysTools.BaseDir ( expandTopDir )
 
 import Data.IORef
 import Control.Arrow ((&&&))
@@ -3465,7 +3465,7 @@ compilerInfo dflags
       -- Next come the settings, so anything else can be overridden
       -- in the settings file (as "lookup" uses the first match for the
       -- key)
-    : map (fmap $ expandDirectories (topDir dflags) (toolDir dflags))
+    : map (fmap $ expandTopDir (topDir dflags))
           (rawSettings dflags)
    ++ [("Project version",             projectVersion dflags),
        ("Edition",                     "Stable Haskell"),
@@ -3525,9 +3525,6 @@ compilerInfo dflags
     showBool False = "NO"
     platform  = targetPlatform dflags
     isWindows = platformOS platform == OSMinGW32
-    useInplaceMinGW = toolSettings_useInplaceMinGW $ toolSettings dflags
-    expandDirectories :: FilePath -> Maybe FilePath -> String -> String
-    expandDirectories topd mtoold = expandToolDir useInplaceMinGW mtoold . expandTopDir topd
 
 -- Note [Special unit-ids]
 -- ~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/compiler/GHC/Settings/IO.hs b/compiler/GHC/Settings/IO.hs
index 63964ff02ff8..b5e949ff18aa 100644
--- a/compiler/GHC/Settings/IO.hs
+++ b/compiler/GHC/Settings/IO.hs
@@ -69,28 +69,23 @@ initSettings top_dir = do
   -- see Note [topdir: How GHC finds its files]
   -- NB: top_dir is assumed to be in standard Unix
   -- format, '/' separated
-  mtool_dir <- liftIO $ findToolDir useInplaceMinGW top_dir
-        -- see Note [tooldir: How GHC finds mingw on Windows]
 
-    -- Escape 'top_dir' and 'mtool_dir', to make sure we don't accidentally
+    -- Escape 'top_dir' to make sure we don't accidentally
     -- introduce unescaped spaces. See #24265 and #25204.
   let escaped_top_dir = escapeArg top_dir
-      escaped_mtool_dir = fmap escapeArg mtool_dir
 
       getSetting_raw key = either pgmError pure $
         getRawSetting settingsFile mySettings key
       getSetting_topDir top key = either pgmError pure $
         getRawFilePathSetting top settingsFile mySettings key
-      getSetting_toolDir top tool key =
-        expandToolDir useInplaceMinGW tool <$> getSetting_topDir top key
 
       getSetting :: String -> ExceptT SettingsError m String
       getSetting key = getSetting_topDir top_dir key
       getToolSetting :: String -> ExceptT SettingsError m String
-      getToolSetting key = getSetting_toolDir top_dir mtool_dir key
+      getToolSetting key = getSetting_topDir top_dir key
       getFlagsSetting :: String -> ExceptT SettingsError m [String]
-      getFlagsSetting key = unescapeArgs <$> getSetting_toolDir escaped_top_dir escaped_mtool_dir key
-        -- Make sure to unescape, as we have escaped top_dir and tool_dir.
+      getFlagsSetting key = unescapeArgs <$> getSetting_topDir escaped_top_dir key
+        -- Make sure to unescape, as we have escaped top_dir.
 
   -- See Note [Settings file] for a little more about this file. We're
   -- just partially applying those functions and throwing 'Left's; they're
@@ -196,7 +191,7 @@ initSettings top_dir = do
     , sFileSettings = FileSettings
       { fileSettings_ghcUsagePath   = ghc_usage_msg_path
       , fileSettings_ghciUsagePath  = ghci_usage_msg_path
-      , fileSettings_toolDir        = mtool_dir
+      , fileSettings_toolDir        = Nothing
       , fileSettings_topDir         = top_dir
       , fileSettings_globalPackageDatabase = globalpkgdb_path
       }
diff --git a/compiler/GHC/SysTools/BaseDir.hs b/compiler/GHC/SysTools/BaseDir.hs
index bbbe0913e438..e3c8628cb027 100644
--- a/compiler/GHC/SysTools/BaseDir.hs
+++ b/compiler/GHC/SysTools/BaseDir.hs
@@ -12,8 +12,8 @@
 -}
 
 module GHC.SysTools.BaseDir
-  ( expandTopDir, expandToolDir
-  , findTopDir, findToolDir
+  ( expandTopDir
+  , findTopDir
   , tryFindTopDir
   ) where
 
@@ -27,11 +27,6 @@ import GHC.Utils.Panic
 import System.Environment (lookupEnv)
 import System.FilePath
 
--- Windows
-#if defined(mingw32_HOST_OS)
-import System.Directory (doesDirectoryExist)
-#endif
-
 {-
 Note [topdir: How GHC finds its files]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -119,14 +114,6 @@ provide the override which allows GHC to instead of using an inplace compiler to
 play nice with the system compiler instead.
 -}
 
--- | Expand occurrences of the @$tooldir@ interpolation in a string
--- on Windows, leave the string untouched otherwise.
-expandToolDir
-  :: Bool -- ^ whether we use the ambient mingw toolchain
-  -> Maybe FilePath -- ^ tooldir
-  -> String -> String
-expandToolDir _ _ s = s
-
 -- | Returns a Unix-format path pointing to TopDir.
 findTopDir :: Maybe String -- Maybe TopDir path (without the '-B' prefix).
            -> IO String    -- TopDir (in Unix format '/' separated)
@@ -152,15 +139,3 @@ tryFindTopDir Nothing
              Just env_top_dir -> return $ Just env_top_dir
              -- Try directory of executable
              Nothing -> getBaseDir
-
-
--- See Note [tooldir: How GHC finds mingw on Windows]
--- 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@.
--- If the distro toolchain is being used we treat Windows the same as Linux
-findToolDir
-  :: Bool -- ^ whether we use the ambient mingw toolchain
-  -> FilePath -- ^ topdir
-  -> IO (Maybe FilePath)
-findToolDir _ _ = return Nothing
diff --git a/testsuite/tests/codeGen/should_run/T25374/all.T b/testsuite/tests/codeGen/should_run/T25374/all.T
index 3676ebc33da6..0e02dc0d263d 100644
--- a/testsuite/tests/codeGen/should_run/T25374/all.T
+++ b/testsuite/tests/codeGen/should_run/T25374/all.T
@@ -1,3 +1,3 @@
 # This shouldn't crash the disassembler
-test('T25374', [fragile(0), extra_hc_opts('+RTS -Di -RTS'), ignore_stderr, req_target_debug_rts], ghci_script, [''])
+test('T25374', [extra_hc_opts('+RTS -Di -RTS'), ignore_stderr, req_target_debug_rts], ghci_script, [''])
 
diff --git a/testsuite/tests/ghci/linking/T25240/all.T b/testsuite/tests/ghci/linking/T25240/all.T
index 0083c227772b..d5cf63c3597f 100644
--- a/testsuite/tests/ghci/linking/T25240/all.T
+++ b/testsuite/tests/ghci/linking/T25240/all.T
@@ -1,3 +1,3 @@
 # skip on darwin because the leading underscores will make the test fail
-test('T25240', [when(leading_underscore(),skip), fragile(0), req_interp, extra_files(['T25240a.hs'])],
+test('T25240', [when(leading_underscore(),skip), req_interp, extra_files(['T25240a.hs'])],
     makefile_test, ['T25240'])
diff --git a/testsuite/tests/rts/T23142.hs b/testsuite/tests/rts/T23142.hs
index 0e667470c26d..75e255c68fb2 100644
--- a/testsuite/tests/rts/T23142.hs
+++ b/testsuite/tests/rts/T23142.hs
@@ -1,5 +1,5 @@
 {-# LANGUAGE UnboxedTuples, MagicHash #-}
-module Main where
+module T23142 where
 
 import GHC.IO
 import GHC.Exts
diff --git a/testsuite/tests/rts/linker/T20494-obj.c b/testsuite/tests/rts/linker/T20494-obj.c
index a792993aa154..ed073d6cfaf0 100644
--- a/testsuite/tests/rts/linker/T20494-obj.c
+++ b/testsuite/tests/rts/linker/T20494-obj.c
@@ -1,15 +1,8 @@
 #include <stdio.h>
-#include <unistd.h>
 
 #define CONSTRUCTOR(prio) __attribute__((constructor(prio)))
 #define DESTRUCTOR(prio)  __attribute__((destructor(prio)))
-#if defined(_WIN32)
 #define PRINT(str) printf(str); fflush(stdout)
-#else
-// don't use "stdout" variable here as it is not properly defined when loading
-// this object in a statically linked GHC.
-#define PRINT(str) dprintf(1,str); fsync(1)
-#endif
 
 CONSTRUCTOR(1000) void constr_a(void) { PRINT("constr a\n"); }
 CONSTRUCTOR(2000) void constr_b(void) { PRINT("constr b\n"); }