Always enable the external interpreter

You can always just not use or even build `iserv`. I don't think the
maintenance cost of the CPP is worth...I can't even tell what the
benefit is.

3 files changed, 15 insertions, 50 deletions

diff --git a/compiler/main/DynFlags.hs b/compiler/main/DynFlags.hs
index 9e9e70ad28..465dd2737b 100644
--- a/compiler/main/DynFlags.hs
+++ b/compiler/main/DynFlags.hs
@@ -4360,26 +4360,25 @@ supportedLanguages = map (flagSpecName . snd) languageFlagsDeps
 supportedLanguageOverlays :: [String]
 supportedLanguageOverlays = map (flagSpecName . snd) safeHaskellFlagsDeps
 
-supportedExtensions :: [String]
-supportedExtensions = concatMap toFlagSpecNamePair xFlags
+supportedExtensions :: PlatformMini -> [String]
+supportedExtensions targetPlatformMini = concatMap toFlagSpecNamePair xFlags
   where
     toFlagSpecNamePair flg
-#if !defined(HAVE_INTERPRETER)
       -- IMPORTANT! Make sure that `ghc --supported-extensions` omits
       -- "TemplateHaskell"/"QuasiQuotes" when it's known not to work out of the
       -- box. See also GHC #11102 and #16331 for more details about
       -- the rationale
-      | flagSpecFlag flg == LangExt.TemplateHaskell  = [noName]
-      | flagSpecFlag flg == LangExt.QuasiQuotes      = [noName]
-#endif
+      | isAIX, flagSpecFlag flg == LangExt.TemplateHaskell  = [noName]
+      | isAIX, flagSpecFlag flg == LangExt.QuasiQuotes      = [noName]
       | otherwise = [name, noName]
       where
+        isAIX = platformMini_os targetPlatformMini == OSAIX
         noName = "No" ++ name
         name = flagSpecName flg
 
-supportedLanguagesAndExtensions :: [String]
-supportedLanguagesAndExtensions =
-    supportedLanguages ++ supportedLanguageOverlays ++ supportedExtensions
+supportedLanguagesAndExtensions :: PlatformMini -> [String]
+supportedLanguagesAndExtensions targetPlatformMini =
+    supportedLanguages ++ supportedLanguageOverlays ++ supportedExtensions targetPlatformMini
 
 -- | These -X<blah> flags cannot be reversed with -XNo<blah>
 languageFlagsDeps :: [(Deprecation, FlagSpec Language)]
diff --git a/compiler/main/DynamicLoading.hs b/compiler/main/DynamicLoading.hs
index 64cc0a1216..ea09a8ceb5 100644
--- a/compiler/main/DynamicLoading.hs
+++ b/compiler/main/DynamicLoading.hs
@@ -3,7 +3,6 @@
 -- | Dynamically lookup up values from modules and loading them.
 module DynamicLoading (
         initializePlugins,
-#if defined(HAVE_INTERPRETER)
         -- * Loading plugins
         loadFrontendPlugin,
 
@@ -19,15 +18,11 @@ module DynamicLoading (
         getValueSafely,
         getHValueSafely,
         lessUnsafeCoerce
-#else
-        pluginError
-#endif
     ) where
 
 import GhcPrelude
 import DynFlags
 
-#if defined(HAVE_INTERPRETER)
 import Linker           ( linkModule, getHValue )
 import GHCi             ( wormhole )
 import SrcLoc           ( noSrcSpan )
@@ -60,28 +55,11 @@ import Control.Monad     ( when, unless )
 import Data.Maybe        ( mapMaybe )
 import GHC.Exts          ( unsafeCoerce# )
 
-#else
-
-import HscTypes         ( HscEnv )
-import Module           ( ModuleName, moduleNameString )
-import Panic
-
-import Data.List        ( intercalate )
-import Control.Monad    ( unless )
-
-#endif
-
 -- | Loads the plugins specified in the pluginModNames field of the dynamic
 -- flags. Should be called after command line arguments are parsed, but before
 -- actual compilation starts. Idempotent operation. Should be re-called if
 -- pluginModNames or pluginModNameOpts changes.
 initializePlugins :: HscEnv -> DynFlags -> IO DynFlags
-#if !defined(HAVE_INTERPRETER)
-initializePlugins _ df
-  = do let pluginMods = pluginModNames df
-       unless (null pluginMods) (pluginError pluginMods)
-       return df
-#else
 initializePlugins hsc_env df
   | map lpModuleName (cachedPlugins df)
          == pluginModNames df -- plugins not changed
@@ -93,10 +71,6 @@ initializePlugins hsc_env df
   = do loadedPlugins <- loadPlugins (hsc_env { hsc_dflags = df })
        return $ df { cachedPlugins = loadedPlugins }
   where argumentsForPlugin p = map snd . filter ((== lpModuleName p) . fst)
-#endif
-
-
-#if defined(HAVE_INTERPRETER)
 
 loadPlugins :: HscEnv -> IO [LoadedPlugin]
 loadPlugins hsc_env
@@ -302,15 +276,3 @@ throwCmdLineErrorS dflags = throwCmdLineError . showSDoc dflags
 
 throwCmdLineError :: String -> IO a
 throwCmdLineError = throwGhcExceptionIO . CmdLineError
-
-#else
-
-pluginError :: [ModuleName] -> a
-pluginError modnames = throwGhcException (CmdLineError msg)
-  where
-    msg = "not built for interactive use - can't load plugins ("
-            -- module names are not z-encoded
-          ++ intercalate ", " (map moduleNameString modnames)
-          ++ ")"
-
-#endif
diff --git a/compiler/main/HeaderInfo.hs b/compiler/main/HeaderInfo.hs
index d534fab1d5..bd984618a4 100644
--- a/compiler/main/HeaderInfo.hs
+++ b/compiler/main/HeaderInfo.hs
@@ -22,6 +22,7 @@ module HeaderInfo ( getImports
 
 import GhcPrelude
 
+import GHC.Platform
 import HscTypes
 import Parser           ( parseHeader )
 import Lexer
@@ -306,10 +307,12 @@ checkExtension :: DynFlags -> Located FastString -> Located String
 checkExtension dflags (dL->L l ext)
 -- Checks if a given extension is valid, and if so returns
 -- its corresponding flag. Otherwise it throws an exception.
- =  let ext' = unpackFS ext in
-    if ext' `elem` supportedLanguagesAndExtensions
+  = if ext' `elem` supported
     then cL l ("-X"++ext')
     else unsupportedExtnError dflags l ext'
+  where
+    ext' = unpackFS ext
+    supported = supportedLanguagesAndExtensions $ platformMini $ targetPlatform dflags
 
 languagePragParseError :: DynFlags -> SrcSpan -> a
 languagePragParseError dflags loc =
@@ -325,7 +328,8 @@ unsupportedExtnError dflags loc unsup =
         text "Unsupported extension: " <> text unsup $$
         if null suggestions then Outputable.empty else text "Perhaps you meant" <+> quotedListWithOr (map text suggestions)
   where
-     suggestions = fuzzyMatch unsup supportedLanguagesAndExtensions
+     supported = supportedLanguagesAndExtensions $ platformMini $ targetPlatform dflags
+     suggestions = fuzzyMatch unsup supported
 
 
 optionsErrorMsgs :: DynFlags -> [String] -> [Located String] -> FilePath -> Messages