Put PlatformConstants into Platform

2 files changed, 15 insertions, 7 deletions

diff --git a/utils/deriveConstants/Main.hs b/utils/deriveConstants/Main.hs
index 1867d824b6..0b6247cf97 100644
--- a/utils/deriveConstants/Main.hs
+++ b/utils/deriveConstants/Main.hs
@@ -873,8 +873,10 @@ getWanted verbose os tmpdir gccProgram gccFlags nmProgram mobjdumpProgram
 writeHaskellType :: FilePath -> [What Fst] -> IO ()
 writeHaskellType fn ws = writeFile fn xs
     where xs = unlines [header, body, footer]
-          header = "data PlatformConstants = PlatformConstants {"
-          footer = "  } deriving Read"
+          header = "module GHC.Platform.Constants where\n\n\
+                   \import Prelude\n\n\
+                   \data PlatformConstants = PlatformConstants {"
+          footer = "  } deriving (Show,Read,Eq)"
           body = intercalate ",\n" (concatMap doWhat ws)
 
           doWhat (GetClosureSize name _) = ["      pc_" ++ name ++ " :: Int"]
@@ -909,16 +911,17 @@ writeHaskellWrappers :: FilePath -> [What Fst] -> IO ()
 writeHaskellWrappers fn ws = writeFile fn xs
     where xs = unlines body
           body = concatMap doWhat ws
+          constants = " (platformConstants (targetPlatform dflags))"
           doWhat (GetFieldType {}) = []
           doWhat (GetClosureSize {}) = []
           doWhat (GetWord name _) = [haskellise name ++ " :: DynFlags -> Int",
-                                    haskellise name ++ " dflags = pc_" ++ name ++ " (platformConstants dflags)"]
+                                    haskellise name ++ " dflags = pc_" ++ name ++ constants]
           doWhat (GetInt name _) = [haskellise name ++ " :: DynFlags -> Int",
-                                   haskellise name ++ " dflags = pc_" ++ name ++ " (platformConstants dflags)"]
+                                   haskellise name ++ " dflags = pc_" ++ name ++ constants]
           doWhat (GetNatural name _) = [haskellise name ++ " :: DynFlags -> Integer",
-                                        haskellise name ++ " dflags = pc_" ++ name ++ " (platformConstants dflags)"]
+                                        haskellise name ++ " dflags = pc_" ++ name ++ constants]
           doWhat (GetBool name _) = [haskellise name ++ " :: DynFlags -> Bool",
-                                     haskellise name ++ " dflags = pc_" ++ name ++ " (platformConstants dflags)"]
+                                     haskellise name ++ " dflags = pc_" ++ name ++ constants]
           doWhat (StructFieldMacro {}) = []
           doWhat (ClosureFieldMacro {}) = []
           doWhat (ClosurePayloadMacro {}) = []
diff --git a/utils/ghc-pkg/Main.hs b/utils/ghc-pkg/Main.hs
index 37fd5ba566..91637f5fab 100644
--- a/utils/ghc-pkg/Main.hs
+++ b/utils/ghc-pkg/Main.hs
@@ -643,6 +643,7 @@ getPkgDatabases verbosity mode use_user use_cache expand_vars my_flags = do
         Right appdir -> do
           -- See Note [Settings File] about this file, and why we need GHC to share it with us.
           let settingsFile = top_dir </> "settings"
+          let constantsFile = top_dir </> "platformConstants"
           exists_settings_file <- doesFileExist settingsFile
           targetPlatformMini <- case exists_settings_file of
             False -> do
@@ -656,7 +657,11 @@ getPkgDatabases verbosity mode use_user use_cache expand_vars my_flags = do
                 -- It's excusable to not have a settings file (for now at
                 -- least) but completely inexcusable to have a malformed one.
                 Nothing -> die $ "Can't parse settings file " ++ show settingsFile
-              case getTargetPlatform settingsFile mySettings of
+              constantsStr <- readFile constantsFile
+              constants <- case maybeReadFuzzy constantsStr of
+                Just s  -> pure s
+                Nothing -> die $ "Can't parse platform constants file " ++ show constantsFile
+              case getTargetPlatform settingsFile mySettings constants of
                 Right platform -> pure $ platformMini platform
                 Left e -> die e
           let subdir = uniqueSubdir targetPlatformMini