{-# LANGUAGE CPP #-} {-# LANGUAGE TupleSections, RecordWildCards #-} {-# LANGUAGE BangPatterns #-} {-# LANGUAGE LambdaCase #-} -- -- (c) The University of Glasgow 2002-2006 -- | The loader -- -- This module deals with the top-level issues of dynamic linking (loading), -- calling the object-code linker and the byte-code linker where necessary. module GHC.Linker.Loader ( Loader (..) , LoaderState (..) , initLoaderState , uninitializedLoader , showLoaderState , getLoaderState -- * Load & Unload , loadExpr , loadDecls , loadPackages , loadModule , loadCmdLineLibs , loadName , unload -- * LoadedEnv , withExtendedLoadedEnv , extendLoadedEnv , deleteFromLoadedEnv ) where import GHC.Prelude import GHC.Settings import GHC.Platform import GHC.Platform.Ways import GHC.Driver.Phases import GHC.Driver.Env import GHC.Driver.Session import GHC.Driver.Ppr import GHC.Driver.Config import GHC.Driver.Config.Diagnostic import GHC.Driver.Config.Finder import GHC.Tc.Utils.Monad import GHC.Runtime.Interpreter import GHCi.RemoteTypes import GHC.ByteCode.Linker import GHC.ByteCode.Asm import GHC.ByteCode.Types import GHC.SysTools import GHC.Types.Basic import GHC.Types.Name import GHC.Types.Name.Env import GHC.Types.SrcLoc import GHC.Types.Unique.DSet import GHC.Types.Unique.DFM import GHC.Utils.Outputable import GHC.Utils.Panic import GHC.Utils.Panic.Plain import GHC.Utils.Error import GHC.Utils.Logger import GHC.Utils.TmpFs import GHC.Unit.Env import GHC.Unit.Finder import GHC.Unit.Module import GHC.Unit.Module.ModIface import GHC.Unit.Module.Deps import GHC.Unit.Home.ModInfo import GHC.Unit.State as Packages import qualified GHC.Data.ShortText as ST import qualified GHC.Data.Maybe as Maybes import GHC.Data.FastString import GHC.Linker.MacOS import GHC.Linker.Dynamic import GHC.Linker.Types -- Standard libraries import Control.Monad import qualified Data.Set as Set import qualified Data.Map as M import Data.Char (isSpace) import Data.IORef import Data.List (intercalate, isPrefixOf, isSuffixOf, nub, partition) import Data.Maybe import Control.Concurrent.MVar import qualified Control.Monad.Catch as MC import System.FilePath import System.Directory import System.IO.Unsafe import System.Environment (lookupEnv) #if defined(mingw32_HOST_OS) import System.Win32.Info (getSystemDirectory) #endif import GHC.Utils.Exception import GHC.Unit.Module.Graph import GHC.Types.SourceFile import GHC.Utils.Misc import GHC.Iface.Load import GHC.Unit.Home import Data.Either import Control.Applicative uninitialised :: a uninitialised = panic "Loader not initialised" modifyLoaderState_ :: Interp -> (LoaderState -> IO LoaderState) -> IO () modifyLoaderState_ interp f = modifyMVar_ (loader_state (interpLoader interp)) (fmap pure . f . fromMaybe uninitialised) modifyLoaderState :: Interp -> (LoaderState -> IO (LoaderState, a)) -> IO a modifyLoaderState interp f = modifyMVar (loader_state (interpLoader interp)) (fmapFst pure . f . fromMaybe uninitialised) where fmapFst f = fmap (\(x, y) -> (f x, y)) getLoaderState :: Interp -> IO (Maybe LoaderState) getLoaderState interp = readMVar (loader_state (interpLoader interp)) emptyLoaderState :: LoaderState emptyLoaderState = LoaderState { closure_env = emptyNameEnv , itbl_env = emptyNameEnv , pkgs_loaded = init_pkgs , bcos_loaded = emptyModuleEnv , objs_loaded = emptyModuleEnv , temp_sos = [] } -- Packages that don't need loading, because the compiler -- shares them with the interpreted program. -- -- The linker's symbol table is populated with RTS symbols using an -- explicit list. See rts/Linker.c for details. where init_pkgs = unitUDFM rtsUnitId (LoadedPkgInfo rtsUnitId [] [] emptyUniqDSet) extendLoadedEnv :: Interp -> [(Name,ForeignHValue)] -> IO () extendLoadedEnv interp new_bindings = modifyLoaderState_ interp $ \pls@LoaderState{..} -> do let new_ce = extendClosureEnv closure_env new_bindings return $! pls{ closure_env = new_ce } -- strictness is important for not retaining old copies of the pls deleteFromLoadedEnv :: Interp -> [Name] -> IO () deleteFromLoadedEnv interp to_remove = modifyLoaderState_ interp $ \pls -> do let ce = closure_env pls let new_ce = delListFromNameEnv ce to_remove return pls{ closure_env = new_ce } -- | Load the module containing the given Name and get its associated 'HValue'. -- -- Throws a 'ProgramError' if loading fails or the name cannot be found. loadName :: Interp -> HscEnv -> Name -> IO (ForeignHValue, [Linkable], PkgsLoaded) loadName interp hsc_env name = do initLoaderState interp hsc_env modifyLoaderState interp $ \pls0 -> do (pls, links, pkgs) <- if not (isExternalName name) then return (pls0, [], emptyUDFM) else do (pls', ok, links, pkgs) <- loadDependencies interp hsc_env pls0 noSrcSpan [nameModule name] if failed ok then throwGhcExceptionIO (ProgramError "") else return (pls', links, pkgs) case lookupNameEnv (closure_env pls) name of Just (_,aa) -> return (pls,(aa, links, pkgs)) Nothing -> assertPpr (isExternalName name) (ppr name) $ do let sym_to_find = nameToCLabel name "closure" m <- lookupClosure interp (unpackFS sym_to_find) r <- case m of Just hvref -> mkFinalizedHValue interp hvref Nothing -> linkFail "GHC.Linker.Loader.loadName" (unpackFS sym_to_find) return (pls,(r, links, pkgs)) loadDependencies :: Interp -> HscEnv -> LoaderState -> SrcSpan -> [Module] -> IO (LoaderState, SuccessFlag, [Linkable], PkgsLoaded) -- ^ returns the set of linkables required loadDependencies interp hsc_env pls span needed_mods = do -- initLoaderState (hsc_dflags hsc_env) dl let dflags = hsc_dflags hsc_env -- The interpreter and dynamic linker can only handle object code built -- the "normal" way, i.e. no non-std ways like profiling or ticky-ticky. -- So here we check the build tag: if we're building a non-standard way -- then we need to find & link object files built the "normal" way. maybe_normal_osuf <- checkNonStdWay dflags interp span -- Find what packages and linkables are required (lnks, all_lnks, pkgs, this_pkgs_needed) <- getLinkDeps hsc_env pls maybe_normal_osuf span needed_mods -- Link the packages and modules required pls1 <- loadPackages' interp hsc_env pkgs pls (pls2, succ) <- loadModuleLinkables interp hsc_env pls1 lnks let this_pkgs_loaded = udfmRestrictKeys all_pkgs_loaded $ getUniqDSet trans_pkgs_needed all_pkgs_loaded = pkgs_loaded pls2 trans_pkgs_needed = unionManyUniqDSets (this_pkgs_needed : [ loaded_pkg_trans_deps pkg | pkg_id <- uniqDSetToList this_pkgs_needed , Just pkg <- [lookupUDFM all_pkgs_loaded pkg_id] ]) return (pls2, succ, all_lnks, this_pkgs_loaded) -- | Temporarily extend the loaded env. withExtendedLoadedEnv :: (ExceptionMonad m) => Interp -> [(Name,ForeignHValue)] -> m a -> m a withExtendedLoadedEnv interp new_env action = MC.bracket (liftIO $ extendLoadedEnv interp new_env) (\_ -> reset_old_env) (\_ -> action) where -- Remember that the linker state might be side-effected -- during the execution of the IO action, and we don't want to -- lose those changes (we might have linked a new module or -- package), so the reset action only removes the names we -- added earlier. reset_old_env = liftIO $ modifyLoaderState_ interp $ \pls -> let cur = closure_env pls new = delListFromNameEnv cur (map fst new_env) in return pls{ closure_env = new } -- | Display the loader state. showLoaderState :: Interp -> IO SDoc showLoaderState interp = do ls <- readMVar (loader_state (interpLoader interp)) let docs = case ls of Nothing -> [ text "Loader not initialised"] Just pls -> [ text "Pkgs:" <+> ppr (map loaded_pkg_uid $ eltsUDFM $ pkgs_loaded pls) , text "Objs:" <+> ppr (moduleEnvElts $ objs_loaded pls) , text "BCOs:" <+> ppr (moduleEnvElts $ bcos_loaded pls) ] return $ withPprStyle defaultDumpStyle $ vcat (text "----- Loader state -----":docs) {- ********************************************************************** Initialisation ********************************************************************* -} -- | Initialise the dynamic linker. This entails -- -- a) Calling the C initialisation procedure, -- -- b) Loading any packages specified on the command line, -- -- c) Loading any packages specified on the command line, now held in the -- @-l@ options in @v_Opt_l@, -- -- d) Loading any @.o\/.dll@ files specified on the command line, now held -- in @ldInputs@, -- -- e) Loading any MacOS frameworks. -- -- NOTE: This function is idempotent; if called more than once, it does -- nothing. This is useful in Template Haskell, where we call it before -- trying to link. -- initLoaderState :: Interp -> HscEnv -> IO () initLoaderState interp hsc_env = do modifyMVar_ (loader_state (interpLoader interp)) $ \pls -> do case pls of Just _ -> return pls Nothing -> Just <$> reallyInitLoaderState interp hsc_env reallyInitLoaderState :: Interp -> HscEnv -> IO LoaderState reallyInitLoaderState interp hsc_env = do -- Initialise the linker state let pls0 = emptyLoaderState -- (a) initialise the C dynamic linker initObjLinker interp -- (b) Load packages from the command-line (Note [preload packages]) pls <- unitEnv_foldWithKey (\k u env -> k >>= \pls' -> loadPackages' interp (hscSetActiveUnitId u hsc_env) (preloadUnits (homeUnitEnv_units env)) pls') (return pls0) (hsc_HUG hsc_env) -- steps (c), (d) and (e) loadCmdLineLibs' interp hsc_env pls loadCmdLineLibs :: Interp -> HscEnv -> IO () loadCmdLineLibs interp hsc_env = do initLoaderState interp hsc_env modifyLoaderState_ interp $ \pls -> loadCmdLineLibs' interp hsc_env pls loadCmdLineLibs' :: Interp -> HscEnv -> LoaderState -> IO LoaderState loadCmdLineLibs' interp hsc_env pls = snd <$> foldM (\(done', pls') cur_uid -> load done' cur_uid pls') (Set.empty, pls) (hsc_all_home_unit_ids hsc_env) where load :: Set.Set UnitId -> UnitId -> LoaderState -> IO (Set.Set UnitId, LoaderState) load done uid pls | uid `Set.member` done = return (done, pls) load done uid pls = do let hsc' = hscSetActiveUnitId uid hsc_env -- Load potential dependencies first (done', pls') <- foldM (\(done', pls') uid -> load done' uid pls') (done, pls) (homeUnitDepends (hsc_units hsc')) pls'' <- loadCmdLineLibs'' interp hsc' pls' return $ (Set.insert uid done', pls'') loadCmdLineLibs'' :: Interp -> HscEnv -> LoaderState -> IO LoaderState loadCmdLineLibs'' interp hsc_env pls = do let dflags@(DynFlags { ldInputs = cmdline_ld_inputs , libraryPaths = lib_paths_base}) = hsc_dflags hsc_env let logger = hsc_logger hsc_env -- (c) Link libraries from the command-line let minus_ls_1 = [ lib | Option ('-':'l':lib) <- cmdline_ld_inputs ] -- On Windows we want to add libpthread by default just as GCC would. -- However because we don't know the actual name of pthread's dll we -- need to defer this to the locateLib call so we can't initialize it -- inside of the rts. Instead we do it here to be able to find the -- import library for pthreads. See #13210. let platform = targetPlatform dflags os = platformOS platform minus_ls = case os of OSMinGW32 -> "pthread" : minus_ls_1 _ -> minus_ls_1 -- See Note [Fork/Exec Windows] gcc_paths <- getGCCPaths logger dflags os lib_paths_env <- addEnvPaths "LIBRARY_PATH" lib_paths_base maybePutStrLn logger "Search directories (user):" maybePutStr logger (unlines $ map (" "++) lib_paths_env) maybePutStrLn logger "Search directories (gcc):" maybePutStr logger (unlines $ map (" "++) gcc_paths) libspecs <- mapM (locateLib interp hsc_env False lib_paths_env gcc_paths) minus_ls -- (d) Link .o files from the command-line classified_ld_inputs <- mapM (classifyLdInput logger platform) [ f | FileOption _ f <- cmdline_ld_inputs ] -- (e) Link any MacOS frameworks let platform = targetPlatform dflags let (framework_paths, frameworks) = if platformUsesFrameworks platform then (frameworkPaths dflags, cmdlineFrameworks dflags) else ([],[]) -- Finally do (c),(d),(e) let cmdline_lib_specs = catMaybes classified_ld_inputs ++ libspecs ++ map Framework frameworks if null cmdline_lib_specs then return pls else do -- Add directories to library search paths, this only has an effect -- on Windows. On Unix OSes this function is a NOP. let all_paths = let paths = takeDirectory (pgm_c dflags) : framework_paths ++ lib_paths_base ++ [ takeDirectory dll | DLLPath dll <- libspecs ] in nub $ map normalise paths let lib_paths = nub $ lib_paths_base ++ gcc_paths all_paths_env <- addEnvPaths "LD_LIBRARY_PATH" all_paths pathCache <- mapM (addLibrarySearchPath interp) all_paths_env let merged_specs = mergeStaticObjects cmdline_lib_specs pls1 <- foldM (preloadLib interp hsc_env lib_paths framework_paths) pls merged_specs maybePutStr logger "final link ... " ok <- resolveObjs interp -- DLLs are loaded, reset the search paths mapM_ (removeLibrarySearchPath interp) $ reverse pathCache if succeeded ok then maybePutStrLn logger "done" else throwGhcExceptionIO (ProgramError "linking extra libraries/objects failed") return pls1 -- | Merge runs of consecutive of 'Objects'. This allows for resolution of -- cyclic symbol references when dynamically linking. Specifically, we link -- together all of the static objects into a single shared object, avoiding -- the issue we saw in #13786. mergeStaticObjects :: [LibrarySpec] -> [LibrarySpec] mergeStaticObjects specs = go [] specs where go :: [FilePath] -> [LibrarySpec] -> [LibrarySpec] go accum (Objects objs : rest) = go (objs ++ accum) rest go accum@(_:_) rest = Objects (reverse accum) : go [] rest go [] (spec:rest) = spec : go [] rest go [] [] = [] {- Note [preload packages] ~~~~~~~~~~~~~~~~~~~~~~~ Why do we need to preload packages from the command line? This is an explanation copied from #2437: I tried to implement the suggestion from #3560, thinking it would be easy, but there are two reasons we link in packages eagerly when they are mentioned on the command line: * So that you can link in extra object files or libraries that depend on the packages. e.g. ghc -package foo -lbar where bar is a C library that depends on something in foo. So we could link in foo eagerly if and only if there are extra C libs or objects to link in, but.... * Haskell code can depend on a C function exported by a package, and the normal dependency tracking that TH uses can't know about these dependencies. The test ghcilink004 relies on this, for example. I conclude that we need two -package flags: one that says "this is a package I want to make available", and one that says "this is a package I want to link in eagerly". Would that be too complicated for users? -} classifyLdInput :: Logger -> Platform -> FilePath -> IO (Maybe LibrarySpec) classifyLdInput logger platform f | isObjectFilename platform f = return (Just (Objects [f])) | isDynLibFilename platform f = return (Just (DLLPath f)) | otherwise = do logMsg logger MCInfo noSrcSpan $ withPprStyle defaultUserStyle (text ("Warning: ignoring unrecognised input `" ++ f ++ "'")) return Nothing preloadLib :: Interp -> HscEnv -> [String] -> [String] -> LoaderState -> LibrarySpec -> IO LoaderState preloadLib interp hsc_env lib_paths framework_paths pls lib_spec = do maybePutStr logger ("Loading object " ++ showLS lib_spec ++ " ... ") case lib_spec of Objects static_ishs -> do (b, pls1) <- preload_statics lib_paths static_ishs maybePutStrLn logger (if b then "done" else "not found") return pls1 Archive static_ish -> do b <- preload_static_archive lib_paths static_ish maybePutStrLn logger (if b then "done" else "not found") return pls DLL dll_unadorned -> do maybe_errstr <- loadDLL interp (platformSOName platform dll_unadorned) case maybe_errstr of Nothing -> maybePutStrLn logger "done" Just mm | platformOS platform /= OSDarwin -> preloadFailed mm lib_paths lib_spec Just mm | otherwise -> do -- As a backup, on Darwin, try to also load a .so file -- since (apparently) some things install that way - see -- ticket #8770. let libfile = ("lib" ++ dll_unadorned) <.> "so" err2 <- loadDLL interp libfile case err2 of Nothing -> maybePutStrLn logger "done" Just _ -> preloadFailed mm lib_paths lib_spec return pls DLLPath dll_path -> do do maybe_errstr <- loadDLL interp dll_path case maybe_errstr of Nothing -> maybePutStrLn logger "done" Just mm -> preloadFailed mm lib_paths lib_spec return pls Framework framework -> if platformUsesFrameworks (targetPlatform dflags) then do maybe_errstr <- loadFramework interp framework_paths framework case maybe_errstr of Nothing -> maybePutStrLn logger "done" Just mm -> preloadFailed mm framework_paths lib_spec return pls else throwGhcExceptionIO (ProgramError "preloadLib Framework") where dflags = hsc_dflags hsc_env logger = hsc_logger hsc_env platform = targetPlatform dflags preloadFailed :: String -> [String] -> LibrarySpec -> IO () preloadFailed sys_errmsg paths spec = do maybePutStr logger "failed.\n" throwGhcExceptionIO $ CmdLineError ( "user specified .o/.so/.DLL could not be loaded (" ++ sys_errmsg ++ ")\nWhilst trying to load: " ++ showLS spec ++ "\nAdditional directories searched:" ++ (if null paths then " (none)" else intercalate "\n" (map (" "++) paths))) -- Not interested in the paths in the static case. preload_statics _paths names = do b <- or <$> mapM doesFileExist names if not b then return (False, pls) else if hostIsDynamic then do pls1 <- dynLoadObjs interp hsc_env pls names return (True, pls1) else do mapM_ (loadObj interp) names return (True, pls) preload_static_archive _paths name = do b <- doesFileExist name if not b then return False else do if hostIsDynamic then throwGhcExceptionIO $ CmdLineError dynamic_msg else loadArchive interp name return True where dynamic_msg = unlines [ "User-specified static library could not be loaded (" ++ name ++ ")" , "Loading static libraries is not supported in this configuration." , "Try using a dynamic library instead." ] {- ********************************************************************** Link a byte-code expression ********************************************************************* -} -- | Load a single expression, /including/ first loading packages and -- modules that this expression depends on. -- -- Raises an IO exception ('ProgramError') if it can't find a compiled -- version of the dependents to load. -- loadExpr :: Interp -> HscEnv -> SrcSpan -> UnlinkedBCO -> IO ForeignHValue loadExpr interp hsc_env span root_ul_bco = do -- Initialise the linker (if it's not been done already) initLoaderState interp hsc_env -- Take lock for the actual work. modifyLoaderState interp $ \pls0 -> do -- Load the packages and modules required (pls, ok, _, _) <- loadDependencies interp hsc_env pls0 span needed_mods if failed ok then throwGhcExceptionIO (ProgramError "") else do -- Load the expression itself let ie = itbl_env pls ce = closure_env pls -- Load the necessary packages and linkables let nobreakarray = error "no break array" bco_ix = mkNameEnv [(unlinkedBCOName root_ul_bco, 0)] resolved <- linkBCO interp ie ce bco_ix nobreakarray root_ul_bco bco_opts <- initBCOOpts (hsc_dflags hsc_env) [root_hvref] <- createBCOs interp bco_opts [resolved] fhv <- mkFinalizedHValue interp root_hvref return (pls, fhv) where free_names = uniqDSetToList (bcoFreeNames root_ul_bco) needed_mods :: [Module] needed_mods = [ nameModule n | n <- free_names, isExternalName n, -- Names from other modules not (isWiredInName n) -- Exclude wired-in names ] -- (see note below) -- Exclude wired-in names because we may not have read -- their interface files, so getLinkDeps will fail -- All wired-in names are in the base package, which we link -- by default, so we can safely ignore them here. dieWith :: DynFlags -> SrcSpan -> SDoc -> IO a dieWith dflags span msg = throwGhcExceptionIO (ProgramError (showSDoc dflags (mkLocMessage MCFatal span msg))) checkNonStdWay :: DynFlags -> Interp -> SrcSpan -> IO (Maybe FilePath) checkNonStdWay _dflags interp _srcspan | ExternalInterp {} <- interpInstance interp = return Nothing -- with -fexternal-interpreter we load the .o files, whatever way -- they were built. If they were built for a non-std way, then -- we will use the appropriate variant of the iserv binary to load them. -- #if-guard the following equations otherwise the pattern match checker will -- complain that they are redundant. #if defined(HAVE_INTERNAL_INTERPRETER) checkNonStdWay dflags _interp srcspan | hostFullWays == targetFullWays = return Nothing -- Only if we are compiling with the same ways as GHC is built -- with, can we dynamically load those object files. (see #3604) | objectSuf_ dflags == normalObjectSuffix && not (null targetFullWays) = failNonStd dflags srcspan | otherwise = return (Just (hostWayTag ++ "o")) where targetFullWays = fullWays (ways dflags) hostWayTag = case waysTag hostFullWays of "" -> "" tag -> tag ++ "_" normalObjectSuffix :: String normalObjectSuffix = phaseInputExt StopLn data Way' = Normal | Prof | Dyn failNonStd :: DynFlags -> SrcSpan -> IO (Maybe FilePath) failNonStd dflags srcspan = dieWith dflags srcspan $ text "Cannot load" <+> pprWay' compWay <+> text "objects when GHC is built" <+> pprWay' ghciWay $$ text "To fix this, either:" $$ text " (1) Use -fexternal-interpreter, or" $$ buildTwiceMsg where compWay | ways dflags `hasWay` WayDyn = Dyn | ways dflags `hasWay` WayProf = Prof | otherwise = Normal ghciWay | hostIsDynamic = Dyn | hostIsProfiled = Prof | otherwise = Normal buildTwiceMsg = case (ghciWay, compWay) of (Normal, Dyn) -> dynamicTooMsg (Dyn, Normal) -> dynamicTooMsg _ -> text " (2) Build the program twice: once" <+> pprWay' ghciWay <> text ", and then" $$ text " " <> pprWay' compWay <+> text "using -osuf to set a different object file suffix." dynamicTooMsg = text " (2) Use -dynamic-too," <+> text "and use -osuf and -dynosuf to set object file suffixes as needed." pprWay' :: Way' -> SDoc pprWay' way = text $ case way of Normal -> "the normal way" Prof -> "with -prof" Dyn -> "with -dynamic" #endif getLinkDeps :: HscEnv -> LoaderState -> Maybe FilePath -- replace object suffixes? -> SrcSpan -- for error messages -> [Module] -- If you need these -> IO ([Linkable], [Linkable], [UnitId], UniqDSet UnitId) -- ... then link these first -- The module and package dependencies for the needed modules are returned. -- See Note [Object File Dependencies] -- Fails with an IO exception if it can't find enough files getLinkDeps hsc_env pls replace_osuf span mods -- Find all the packages and linkables that a set of modules depends on = do { -- 1. Find the dependent home-pkg-modules/packages from each iface -- (omitting modules from the interactive package, which is already linked) ; (mods_s, pkgs_s) <- -- Why two code paths here? There is a significant amount of repeated work -- performed calculating transitive dependencies -- if --make uses the oneShot code path (see MultiLayerModulesTH_* tests) if isOneShot (ghcMode dflags) then follow_deps (filterOut isInteractiveModule mods) emptyUniqDSet emptyUniqDSet; else do (pkgs, mmods) <- unzip <$> mapM get_mod_info all_home_mods return (catMaybes mmods, unionManyUniqDSets (init_pkg_set : pkgs)) ; let -- 2. Exclude ones already linked -- Main reason: avoid findModule calls in get_linkable (mods_needed, links_got) = partitionEithers (map split_mods mods_s) pkgs_needed = eltsUDFM $ getUniqDSet pkgs_s `minusUDFM` pkgs_loaded pls split_mods mod = let is_linked = findModuleLinkable_maybe (objs_loaded pls) mod <|> findModuleLinkable_maybe (bcos_loaded pls) mod in case is_linked of Just linkable -> Right linkable Nothing -> Left mod -- 3. For each dependent module, find its linkable -- This will either be in the HPT or (in the case of one-shot -- compilation) we may need to use maybe_getFileLinkable ; let { osuf = objectSuf dflags } ; lnks_needed <- mapM (get_linkable osuf) mods_needed ; return (lnks_needed, links_got ++ lnks_needed, pkgs_needed, pkgs_s) } where dflags = hsc_dflags hsc_env mod_graph = hsc_mod_graph hsc_env -- This code is used in `--make` mode to calculate the home package and unit dependencies -- for a set of modules. -- -- It is significantly more efficient to use the shared transitive dependency -- calculation than to compute the transitive dependency set in the same manner as oneShot mode. -- It is also a matter of correctness to use the module graph so that dependencies between home units -- is resolved correctly. make_deps_loop :: (UniqDSet UnitId, Set.Set NodeKey) -> [ModNodeKeyWithUid] -> (UniqDSet UnitId, Set.Set NodeKey) make_deps_loop found [] = found make_deps_loop found@(found_units, found_mods) (nk:nexts) | NodeKey_Module nk `Set.member` found_mods = make_deps_loop found nexts | otherwise = case M.lookup (NodeKey_Module nk) (mgTransDeps mod_graph) of Just trans_deps -> let deps = Set.insert (NodeKey_Module nk) trans_deps -- See #936 and the ghci.prog007 test for why we have to continue traversing through -- boot modules. todo_boot_mods = [ModNodeKeyWithUid (GWIB mn NotBoot) uid | NodeKey_Module (ModNodeKeyWithUid (GWIB mn IsBoot) uid) <- Set.toList trans_deps] in make_deps_loop (found_units, deps `Set.union` found_mods) (todo_boot_mods ++ nexts) Nothing -> let (ModNodeKeyWithUid _ uid) = nk in make_deps_loop (addOneToUniqDSet found_units uid, found_mods) nexts mkNk m = ModNodeKeyWithUid (GWIB (moduleName m) NotBoot) (moduleUnitId m) (init_pkg_set, all_deps) = make_deps_loop (emptyUniqDSet, Set.empty) $ map mkNk (filterOut isInteractiveModule mods) all_home_mods = [with_uid | NodeKey_Module with_uid <- Set.toList all_deps] get_mod_info (ModNodeKeyWithUid gwib uid) = case lookupHug (hsc_HUG hsc_env) uid (gwib_mod gwib) of Just hmi -> let iface = (hm_iface hmi) mmod = case mi_hsc_src iface of HsBootFile -> link_boot_mod_error (mi_module iface) _ -> return $ Just (mi_module iface) in (mkUniqDSet $ Set.toList $ dep_direct_pkgs (mi_deps iface),) <$> mmod Nothing -> let err = text "getLinkDeps: Home module not loaded" <+> ppr (gwib_mod gwib) <+> ppr uid in throwGhcExceptionIO (ProgramError (showSDoc dflags err)) -- This code is used in one-shot mode to traverse downwards through the HPT -- to find all link dependencies. -- The ModIface contains the transitive closure of the module dependencies -- within the current package, *except* for boot modules: if we encounter -- a boot module, we have to find its real interface and discover the -- dependencies of that. Hence we need to traverse the dependency -- tree recursively. See bug #936, testcase ghci/prog007. follow_deps :: [Module] -- modules to follow -> UniqDSet Module -- accum. module dependencies -> UniqDSet UnitId -- accum. package dependencies -> IO ([Module], UniqDSet UnitId) -- result follow_deps [] acc_mods acc_pkgs = return (uniqDSetToList acc_mods, acc_pkgs) follow_deps (mod:mods) acc_mods acc_pkgs = do mb_iface <- initIfaceCheck (text "getLinkDeps") hsc_env $ loadInterface msg mod (ImportByUser NotBoot) iface <- case mb_iface of Maybes.Failed err -> throwGhcExceptionIO (ProgramError (showSDoc dflags err)) Maybes.Succeeded iface -> return iface when (mi_boot iface == IsBoot) $ link_boot_mod_error mod let pkg = moduleUnit mod deps = mi_deps iface pkg_deps = dep_direct_pkgs deps (boot_deps, mod_deps) = flip partitionWith (Set.toList (dep_direct_mods deps)) $ \case (_, GWIB m IsBoot) -> Left m (_, GWIB m NotBoot) -> Right m mod_deps' = case hsc_home_unit_maybe hsc_env of Nothing -> [] Just home_unit -> filter (not . (`elementOfUniqDSet` acc_mods)) (map (mkHomeModule home_unit) $ (boot_deps ++ mod_deps)) acc_mods' = case hsc_home_unit_maybe hsc_env of Nothing -> acc_mods Just home_unit -> addListToUniqDSet acc_mods (mod : map (mkHomeModule home_unit) mod_deps) acc_pkgs' = addListToUniqDSet acc_pkgs (Set.toList pkg_deps) case hsc_home_unit_maybe hsc_env of Just home_unit | isHomeUnit home_unit pkg -> follow_deps (mod_deps' ++ mods) acc_mods' acc_pkgs' _ -> follow_deps mods acc_mods (addOneToUniqDSet acc_pkgs' (toUnitId pkg)) where msg = text "need to link module" <+> ppr mod <+> text "due to use of Template Haskell" link_boot_mod_error :: Module -> IO a link_boot_mod_error mod = throwGhcExceptionIO (ProgramError (showSDoc dflags ( text "module" <+> ppr mod <+> text "cannot be linked; it is only available as a boot module"))) no_obj :: Outputable a => a -> IO b no_obj mod = dieWith dflags span $ text "cannot find object file for module " <> quotes (ppr mod) $$ while_linking_expr while_linking_expr = text "while linking an interpreted expression" -- This one is a build-system bug get_linkable osuf mod -- A home-package module | Just mod_info <- lookupHugByModule mod (hsc_HUG hsc_env) = adjust_linkable (Maybes.expectJust "getLinkDeps" (hm_linkable mod_info)) | otherwise = do -- It's not in the HPT because we are in one shot mode, -- so use the Finder to get a ModLocation... case hsc_home_unit_maybe hsc_env of Nothing -> no_obj mod Just home_unit -> do let fc = hsc_FC hsc_env let dflags = hsc_dflags hsc_env let fopts = initFinderOpts dflags mb_stuff <- findHomeModule fc fopts home_unit (moduleName mod) case mb_stuff of Found loc mod -> found loc mod _ -> no_obj (moduleName mod) where found loc mod = do { -- ...and then find the linkable for it mb_lnk <- findObjectLinkableMaybe mod loc ; case mb_lnk of { Nothing -> no_obj mod ; Just lnk -> adjust_linkable lnk }} adjust_linkable lnk | Just new_osuf <- replace_osuf = do new_uls <- mapM (adjust_ul new_osuf) (linkableUnlinked lnk) return lnk{ linkableUnlinked=new_uls } | otherwise = return lnk adjust_ul new_osuf (DotO file) = do massert (osuf `isSuffixOf` file) let file_base = fromJust (stripExtension osuf file) new_file = file_base <.> new_osuf ok <- doesFileExist new_file if (not ok) then dieWith dflags span $ text "cannot find object file " <> quotes (text new_file) $$ while_linking_expr else return (DotO new_file) adjust_ul _ (DotA fp) = panic ("adjust_ul DotA " ++ show fp) adjust_ul _ (DotDLL fp) = panic ("adjust_ul DotDLL " ++ show fp) adjust_ul _ l@(BCOs {}) = return l {- ********************************************************************** Loading a Decls statement ********************************************************************* -} loadDecls :: Interp -> HscEnv -> SrcSpan -> CompiledByteCode -> IO ([(Name, ForeignHValue)], [Linkable], PkgsLoaded) loadDecls interp hsc_env span cbc@CompiledByteCode{..} = do -- Initialise the linker (if it's not been done already) initLoaderState interp hsc_env -- Take lock for the actual work. modifyLoaderState interp $ \pls0 -> do -- Link the packages and modules required (pls, ok, links_needed, units_needed) <- loadDependencies interp hsc_env pls0 span needed_mods if failed ok then throwGhcExceptionIO (ProgramError "") else do -- Link the expression itself let ie = plusNameEnv (itbl_env pls) bc_itbls ce = closure_env pls -- Link the necessary packages and linkables bco_opts <- initBCOOpts (hsc_dflags hsc_env) new_bindings <- linkSomeBCOs bco_opts interp ie ce [cbc] nms_fhvs <- makeForeignNamedHValueRefs interp new_bindings let pls2 = pls { closure_env = extendClosureEnv ce nms_fhvs , itbl_env = ie } return (pls2, (nms_fhvs, links_needed, units_needed)) where free_names = uniqDSetToList $ foldr (unionUniqDSets . bcoFreeNames) emptyUniqDSet bc_bcos needed_mods :: [Module] needed_mods = [ nameModule n | n <- free_names, isExternalName n, -- Names from other modules not (isWiredInName n) -- Exclude wired-in names ] -- (see note below) -- Exclude wired-in names because we may not have read -- their interface files, so getLinkDeps will fail -- All wired-in names are in the base package, which we link -- by default, so we can safely ignore them here. {- ********************************************************************** Loading a single module ********************************************************************* -} loadModule :: Interp -> HscEnv -> Module -> IO () loadModule interp hsc_env mod = do initLoaderState interp hsc_env modifyLoaderState_ interp $ \pls -> do (pls', ok, _, _) <- loadDependencies interp hsc_env pls noSrcSpan [mod] if failed ok then throwGhcExceptionIO (ProgramError "could not load module") else return pls' {- ********************************************************************** Link some linkables The linkables may consist of a mixture of byte-code modules and object modules ********************************************************************* -} loadModuleLinkables :: Interp -> HscEnv -> LoaderState -> [Linkable] -> IO (LoaderState, SuccessFlag) loadModuleLinkables interp hsc_env pls linkables = mask_ $ do -- don't want to be interrupted by ^C in here let (objs, bcos) = partition isObjectLinkable (concatMap partitionLinkable linkables) bco_opts <- initBCOOpts (hsc_dflags hsc_env) -- Load objects first; they can't depend on BCOs (pls1, ok_flag) <- loadObjects interp hsc_env pls objs if failed ok_flag then return (pls1, Failed) else do pls2 <- dynLinkBCOs bco_opts interp pls1 bcos return (pls2, Succeeded) -- HACK to support f-x-dynamic in the interpreter; no other purpose partitionLinkable :: Linkable -> [Linkable] partitionLinkable li = let li_uls = linkableUnlinked li li_uls_obj = filter isObject li_uls li_uls_bco = filter isInterpretable li_uls in case (li_uls_obj, li_uls_bco) of (_:_, _:_) -> [li {linkableUnlinked=li_uls_obj}, li {linkableUnlinked=li_uls_bco}] _ -> [li] findModuleLinkable_maybe :: LinkableSet -> Module -> Maybe Linkable findModuleLinkable_maybe = lookupModuleEnv linkableInSet :: Linkable -> LinkableSet -> Bool linkableInSet l objs_loaded = case findModuleLinkable_maybe objs_loaded (linkableModule l) of Nothing -> False Just m -> linkableTime l == linkableTime m {- ********************************************************************** The object-code linker ********************************************************************* -} -- | Load the object files and link them -- -- If the interpreter uses dynamic-linking, build a shared library and load it. -- Otherwise, use the RTS linker. loadObjects :: Interp -> HscEnv -> LoaderState -> [Linkable] -> IO (LoaderState, SuccessFlag) loadObjects interp hsc_env pls objs = do let (objs_loaded', new_objs) = rmDupLinkables (objs_loaded pls) objs pls1 = pls { objs_loaded = objs_loaded' } unlinkeds = concatMap linkableUnlinked new_objs wanted_objs = map nameOfObject unlinkeds if interpreterDynamic interp then do pls2 <- dynLoadObjs interp hsc_env pls1 wanted_objs return (pls2, Succeeded) else do mapM_ (loadObj interp) wanted_objs -- Link them all together ok <- resolveObjs interp -- If resolving failed, unload all our -- object modules and carry on if succeeded ok then return (pls1, Succeeded) else do pls2 <- unload_wkr interp [] pls1 return (pls2, Failed) -- | Create a shared library containing the given object files and load it. dynLoadObjs :: Interp -> HscEnv -> LoaderState -> [FilePath] -> IO LoaderState dynLoadObjs _ _ pls [] = return pls dynLoadObjs interp hsc_env pls@LoaderState{..} objs = do let unit_env = hsc_unit_env hsc_env let dflags = hsc_dflags hsc_env let logger = hsc_logger hsc_env let tmpfs = hsc_tmpfs hsc_env let platform = ue_platform unit_env let minus_ls = [ lib | Option ('-':'l':lib) <- ldInputs dflags ] let minus_big_ls = [ lib | Option ('-':'L':lib) <- ldInputs dflags ] (soFile, libPath , libName) <- newTempLibName logger tmpfs (tmpDir dflags) TFL_CurrentModule (platformSOExt platform) let dflags2 = dflags { -- We don't want the original ldInputs in -- (they're already linked in), but we do want -- to link against previous dynLoadObjs -- libraries if there were any, so that the linker -- can resolve dependencies when it loads this -- library. ldInputs = concatMap (\l -> [ Option ("-l" ++ l) ]) (nub $ snd <$> temp_sos) ++ concatMap (\lp -> Option ("-L" ++ lp) : if useXLinkerRPath dflags (platformOS platform) then [ Option "-Xlinker" , Option "-rpath" , Option "-Xlinker" , Option lp ] else []) (nub $ fst <$> temp_sos) ++ concatMap (\lp -> Option ("-L" ++ lp) : if useXLinkerRPath dflags (platformOS platform) then [ Option "-Xlinker" , Option "-rpath" , Option "-Xlinker" , Option lp ] else []) minus_big_ls -- See Note [-Xlinker -rpath vs -Wl,-rpath] ++ map (\l -> Option ("-l" ++ l)) minus_ls, -- Add -l options and -L options from dflags. -- -- When running TH for a non-dynamic way, we still -- need to make -l flags to link against the dynamic -- libraries, so we need to add WayDyn to ways. -- -- Even if we're e.g. profiling, we still want -- the vanilla dynamic libraries, so we set the -- ways / build tag to be just WayDyn. targetWays_ = Set.singleton WayDyn, outputFile_ = Just soFile } -- link all "loaded packages" so symbols in those can be resolved -- Note: We are loading packages with local scope, so to see the -- symbols in this link we must link all loaded packages again. linkDynLib logger tmpfs dflags2 unit_env objs (loaded_pkg_uid <$> eltsUDFM pkgs_loaded) -- if we got this far, extend the lifetime of the library file changeTempFilesLifetime tmpfs TFL_GhcSession [soFile] m <- loadDLL interp soFile case m of Nothing -> return $! pls { temp_sos = (libPath, libName) : temp_sos } Just err -> linkFail msg err where msg = "GHC.Linker.Loader.dynLoadObjs: Loading temp shared object failed" rmDupLinkables :: LinkableSet -- Already loaded -> [Linkable] -- New linkables -> (LinkableSet, -- New loaded set (including new ones) [Linkable]) -- New linkables (excluding dups) rmDupLinkables already ls = go already [] ls where go already extras [] = (already, extras) go already extras (l:ls) | linkableInSet l already = go already extras ls | otherwise = go (extendModuleEnv already (linkableModule l) l) (l:extras) ls {- ********************************************************************** The byte-code linker ********************************************************************* -} dynLinkBCOs :: BCOOpts -> Interp -> LoaderState -> [Linkable] -> IO LoaderState dynLinkBCOs bco_opts interp pls bcos = do let (bcos_loaded', new_bcos) = rmDupLinkables (bcos_loaded pls) bcos pls1 = pls { bcos_loaded = bcos_loaded' } unlinkeds :: [Unlinked] unlinkeds = concatMap linkableUnlinked new_bcos cbcs :: [CompiledByteCode] cbcs = map byteCodeOfObject unlinkeds ies = map bc_itbls cbcs gce = closure_env pls final_ie = foldr plusNameEnv (itbl_env pls) ies names_and_refs <- linkSomeBCOs bco_opts interp final_ie gce cbcs -- We only want to add the external ones to the ClosureEnv let (to_add, to_drop) = partition (isExternalName.fst) names_and_refs -- Immediately release any HValueRefs we're not going to add freeHValueRefs interp (map snd to_drop) -- Wrap finalizers on the ones we want to keep new_binds <- makeForeignNamedHValueRefs interp to_add return pls1 { closure_env = extendClosureEnv gce new_binds, itbl_env = final_ie } -- Link a bunch of BCOs and return references to their values linkSomeBCOs :: BCOOpts -> Interp -> ItblEnv -> ClosureEnv -> [CompiledByteCode] -> IO [(Name,HValueRef)] -- The returned HValueRefs are associated 1-1 with -- the incoming unlinked BCOs. Each gives the -- value of the corresponding unlinked BCO linkSomeBCOs bco_opts interp ie ce mods = foldr fun do_link mods [] where fun CompiledByteCode{..} inner accum = case bc_breaks of Nothing -> inner ((panic "linkSomeBCOs: no break array", bc_bcos) : accum) Just mb -> withForeignRef (modBreaks_flags mb) $ \breakarray -> inner ((breakarray, bc_bcos) : accum) do_link [] = return [] do_link mods = do let flat = [ (breakarray, bco) | (breakarray, bcos) <- mods, bco <- bcos ] names = map (unlinkedBCOName . snd) flat bco_ix = mkNameEnv (zip names [0..]) resolved <- sequence [ linkBCO interp ie ce bco_ix breakarray bco | (breakarray, bco) <- flat ] hvrefs <- createBCOs interp bco_opts resolved return (zip names hvrefs) -- | Useful to apply to the result of 'linkSomeBCOs' makeForeignNamedHValueRefs :: Interp -> [(Name,HValueRef)] -> IO [(Name,ForeignHValue)] makeForeignNamedHValueRefs interp bindings = mapM (\(n, hvref) -> (n,) <$> mkFinalizedHValue interp hvref) bindings {- ********************************************************************** Unload some object modules ********************************************************************* -} -- --------------------------------------------------------------------------- -- | Unloading old objects ready for a new compilation sweep. -- -- The compilation manager provides us with a list of linkables that it -- considers \"stable\", i.e. won't be recompiled this time around. For -- each of the modules current linked in memory, -- -- * if the linkable is stable (and it's the same one -- the user may have -- recompiled the module on the side), we keep it, -- -- * otherwise, we unload it. -- -- * we also implicitly unload all temporary bindings at this point. -- unload :: Interp -> HscEnv -> [Linkable] -- ^ The linkables to *keep*. -> IO () unload interp hsc_env linkables = mask_ $ do -- mask, so we're safe from Ctrl-C in here -- Initialise the linker (if it's not been done already) initLoaderState interp hsc_env new_pls <- modifyLoaderState interp $ \pls -> do pls1 <- unload_wkr interp linkables pls return (pls1, pls1) let logger = hsc_logger hsc_env debugTraceMsg logger 3 $ text "unload: retaining objs" <+> ppr (moduleEnvElts $ objs_loaded new_pls) debugTraceMsg logger 3 $ text "unload: retaining bcos" <+> ppr (moduleEnvElts $ bcos_loaded new_pls) return () unload_wkr :: Interp -> [Linkable] -- stable linkables -> LoaderState -> IO LoaderState -- Does the core unload business -- (the wrapper blocks exceptions and deals with the LS get and put) unload_wkr interp keep_linkables pls@LoaderState{..} = do -- NB. careful strictness here to avoid keeping the old LS when -- we're unloading some code. -fghci-leak-check with the tests in -- testsuite/ghci can detect space leaks here. let (objs_to_keep', bcos_to_keep') = partition isObjectLinkable keep_linkables objs_to_keep = mkLinkableSet objs_to_keep' bcos_to_keep = mkLinkableSet bcos_to_keep' discard keep l = not (linkableInSet l keep) (objs_to_unload, remaining_objs_loaded) = partitionModuleEnv (discard objs_to_keep) objs_loaded (bcos_to_unload, remaining_bcos_loaded) = partitionModuleEnv (discard bcos_to_keep) bcos_loaded linkables_to_unload = moduleEnvElts objs_to_unload ++ moduleEnvElts bcos_to_unload mapM_ unloadObjs linkables_to_unload -- If we unloaded any object files at all, we need to purge the cache -- of lookupSymbol results. when (not (null (filter (not . null . linkableObjs) linkables_to_unload))) $ purgeLookupSymbolCache interp let -- Note that we want to remove all *local* -- (i.e. non-isExternal) names too (these are the -- temporary bindings from the command line). keep_name :: (Name, a) -> Bool keep_name (n,_) = isExternalName n && nameModule n `elemModuleEnv` remaining_bcos_loaded itbl_env' = filterNameEnv keep_name itbl_env closure_env' = filterNameEnv keep_name closure_env !new_pls = pls { itbl_env = itbl_env', closure_env = closure_env', bcos_loaded = remaining_bcos_loaded, objs_loaded = remaining_objs_loaded } return new_pls where unloadObjs :: Linkable -> IO () unloadObjs lnk | interpreterDynamic interp = return () -- We don't do any cleanup when linking objects with the -- dynamic linker. Doing so introduces extra complexity for -- not much benefit. | otherwise = mapM_ (unloadObj interp) [f | DotO f <- linkableUnlinked lnk] -- The components of a BCO linkable may contain -- dot-o files. Which is very confusing. -- -- But the BCO parts can be unlinked just by -- letting go of them (plus of course depopulating -- the symbol table which is done in the main body) showLS :: LibrarySpec -> String showLS (Objects nms) = "(static) [" ++ intercalate ", " nms ++ "]" showLS (Archive nm) = "(static archive) " ++ nm showLS (DLL nm) = "(dynamic) " ++ nm showLS (DLLPath nm) = "(dynamic) " ++ nm showLS (Framework nm) = "(framework) " ++ nm -- | Load exactly the specified packages, and their dependents (unless of -- course they are already loaded). The dependents are loaded -- automatically, and it doesn't matter what order you specify the input -- packages. -- loadPackages :: Interp -> HscEnv -> [UnitId] -> IO () -- NOTE: in fact, since each module tracks all the packages it depends on, -- we don't really need to use the package-config dependencies. -- -- However we do need the package-config stuff (to find aux libs etc), -- and following them lets us load libraries in the right order, which -- perhaps makes the error message a bit more localised if we get a link -- failure. So the dependency walking code is still here. loadPackages interp hsc_env new_pkgs = do -- It's probably not safe to try to load packages concurrently, so we take -- a lock. initLoaderState interp hsc_env modifyLoaderState_ interp $ \pls -> loadPackages' interp hsc_env new_pkgs pls loadPackages' :: Interp -> HscEnv -> [UnitId] -> LoaderState -> IO LoaderState loadPackages' interp hsc_env new_pks pls = do pkgs' <- link (pkgs_loaded pls) new_pks return $! pls { pkgs_loaded = pkgs' } where link :: PkgsLoaded -> [UnitId] -> IO PkgsLoaded link pkgs new_pkgs = foldM link_one pkgs new_pkgs link_one pkgs new_pkg | new_pkg `elemUDFM` pkgs -- Already linked = return pkgs | Just pkg_cfg <- lookupUnitId (hsc_units hsc_env) new_pkg = do { let deps = unitDepends pkg_cfg -- Link dependents first ; pkgs' <- link pkgs deps -- Now link the package itself ; (hs_cls, extra_cls) <- loadPackage interp hsc_env pkg_cfg ; let trans_deps = unionManyUniqDSets [ addOneToUniqDSet (loaded_pkg_trans_deps loaded_pkg_info) dep_pkg | dep_pkg <- deps , Just loaded_pkg_info <- pure (lookupUDFM pkgs' dep_pkg) ] ; return (addToUDFM pkgs' new_pkg (LoadedPkgInfo new_pkg hs_cls extra_cls trans_deps)) } | otherwise = throwGhcExceptionIO (CmdLineError ("unknown package: " ++ unpackFS (unitIdFS new_pkg))) loadPackage :: Interp -> HscEnv -> UnitInfo -> IO ([LibrarySpec], [LibrarySpec]) loadPackage interp hsc_env pkg = do let dflags = hsc_dflags hsc_env let logger = hsc_logger hsc_env platform = targetPlatform dflags is_dyn = interpreterDynamic interp dirs | is_dyn = map ST.unpack $ Packages.unitLibraryDynDirs pkg | otherwise = map ST.unpack $ Packages.unitLibraryDirs pkg let hs_libs = map ST.unpack $ Packages.unitLibraries pkg -- The FFI GHCi import lib isn't needed as -- GHC.Linker.Loader + rts/Linker.c link the -- interpreted references to FFI to the compiled FFI. -- We therefore filter it out so that we don't get -- duplicate symbol errors. hs_libs' = filter ("HSffi" /=) hs_libs -- Because of slight differences between the GHC dynamic linker and -- the native system linker some packages have to link with a -- different list of libraries when using GHCi. Examples include: libs -- that are actually gnu ld scripts, and the possibility that the .a -- libs do not exactly match the .so/.dll equivalents. So if the -- package file provides an "extra-ghci-libraries" field then we use -- that instead of the "extra-libraries" field. extdeplibs = map ST.unpack (if null (Packages.unitExtDepLibsGhc pkg) then Packages.unitExtDepLibsSys pkg else Packages.unitExtDepLibsGhc pkg) linkerlibs = [ lib | '-':'l':lib <- (map ST.unpack $ Packages.unitLinkerOptions pkg) ] extra_libs = extdeplibs ++ linkerlibs -- See Note [Fork/Exec Windows] gcc_paths <- getGCCPaths logger dflags (platformOS platform) dirs_env <- addEnvPaths "LIBRARY_PATH" dirs hs_classifieds <- mapM (locateLib interp hsc_env True dirs_env gcc_paths) hs_libs' extra_classifieds <- mapM (locateLib interp hsc_env False dirs_env gcc_paths) extra_libs let classifieds = hs_classifieds ++ extra_classifieds -- Complication: all the .so's must be loaded before any of the .o's. let known_dlls = [ dll | DLLPath dll <- classifieds ] #if defined(CAN_LOAD_DLL) dlls = [ dll | DLL dll <- classifieds ] #endif objs = [ obj | Objects objs <- classifieds , obj <- objs ] archs = [ arch | Archive arch <- classifieds ] -- Add directories to library search paths let dll_paths = map takeDirectory known_dlls all_paths = nub $ map normalise $ dll_paths ++ dirs all_paths_env <- addEnvPaths "LD_LIBRARY_PATH" all_paths pathCache <- mapM (addLibrarySearchPath interp) all_paths_env maybePutSDoc logger (text "Loading unit " <> pprUnitInfoForUser pkg <> text " ... ") #if defined(CAN_LOAD_DLL) loadFrameworks interp platform pkg -- See Note [Crash early load_dyn and locateLib] -- Crash early if can't load any of `known_dlls` mapM_ (load_dyn interp hsc_env True) known_dlls -- For remaining `dlls` crash early only when there is surely -- no package's DLL around ... (not is_dyn) mapM_ (load_dyn interp hsc_env (not is_dyn) . platformSOName platform) dlls #endif -- After loading all the DLLs, we can load the static objects. -- Ordering isn't important here, because we do one final link -- step to resolve everything. mapM_ (loadObj interp) objs mapM_ (loadArchive interp) archs maybePutStr logger "linking ... " ok <- resolveObjs interp -- DLLs are loaded, reset the search paths -- Import libraries will be loaded via loadArchive so only -- reset the DLL search path after all archives are loaded -- as well. mapM_ (removeLibrarySearchPath interp) $ reverse pathCache if succeeded ok then do maybePutStrLn logger "done." return (hs_classifieds, extra_classifieds) else let errmsg = text "unable to load unit `" <> pprUnitInfoForUser pkg <> text "'" in throwGhcExceptionIO (InstallationError (showSDoc dflags errmsg)) {- Note [Crash early load_dyn and locateLib] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ If a package is "normal" (exposes it's code from more than zero Haskell modules, unlike e.g. that in ghcilink004) and is built "dyn" way, then it has it's code compiled and linked into the DLL, which GHCi linker picks when loading the package's code (see the big comment in the beginning of `locateLib`). When loading DLLs, GHCi linker simply calls the system's `dlopen` or `LoadLibrary` APIs. This is quite different from the case when GHCi linker loads an object file or static library. When loading an object file or static library GHCi linker parses them and resolves all symbols "manually". These object file or static library may reference some external symbols defined in some external DLLs. And GHCi should know which these external DLLs are. But when GHCi loads a DLL, it's the *system* linker who manages all the necessary dependencies, and it is able to load this DLL not having any extra info. Thus we don't *have to* crash in this case even if we are unable to load any supposed dependencies explicitly. Suppose during GHCi session a client of the package wants to `foreign import` a symbol which isn't exposed by the package DLL, but is exposed by such an external (dependency) DLL. If the DLL isn't *explicitly* loaded because `load_dyn` failed to do this, then the client code eventually crashes because the GHCi linker isn't able to locate this symbol (GHCi linker maintains a list of explicitly loaded DLLs it looks into when trying to find a symbol). This is why we still should try to load all the dependency DLLs even though we know that the system linker loads them implicitly when loading the package DLL. Why we still keep the `crash_early` opportunity then not allowing such a permissive behaviour for any DLLs? Well, we, perhaps, improve a user experience in some cases slightly. But if it happens there exist other corner cases where our current usage of `crash_early` flag is overly restrictive, we may lift the restriction very easily. -} #if defined(CAN_LOAD_DLL) -- we have already searched the filesystem; the strings passed to load_dyn -- can be passed directly to loadDLL. They are either fully-qualified -- ("/usr/lib/libfoo.so"), or unqualified ("libfoo.so"). In the latter case, -- loadDLL is going to search the system paths to find the library. load_dyn :: Interp -> HscEnv -> Bool -> FilePath -> IO () load_dyn interp hsc_env crash_early dll = do r <- loadDLL interp dll case r of Nothing -> return () Just err -> if crash_early then cmdLineErrorIO err else when (diag_wopt Opt_WarnMissedExtraSharedLib diag_opts) $ logMsg logger (mkMCDiagnostic diag_opts $ WarningWithFlag Opt_WarnMissedExtraSharedLib) noSrcSpan $ withPprStyle defaultUserStyle (note err) where diag_opts = initDiagOpts (hsc_dflags hsc_env) logger = hsc_logger hsc_env note err = vcat $ map text [ err , "It's OK if you don't want to use symbols from it directly." , "(the package DLL is loaded by the system linker" , " which manages dependencies by itself)." ] loadFrameworks :: Interp -> Platform -> UnitInfo -> IO () loadFrameworks interp platform pkg = when (platformUsesFrameworks platform) $ mapM_ load frameworks where fw_dirs = map ST.unpack $ Packages.unitExtDepFrameworkDirs pkg frameworks = map ST.unpack $ Packages.unitExtDepFrameworks pkg load fw = do r <- loadFramework interp fw_dirs fw case r of Nothing -> return () Just err -> cmdLineErrorIO ("can't load framework: " ++ fw ++ " (" ++ err ++ ")" ) #endif -- Try to find an object file for a given library in the given paths. -- If it isn't present, we assume that addDLL in the RTS can find it, -- which generally means that it should be a dynamic library in the -- standard system search path. -- For GHCi we tend to prefer dynamic libraries over static ones as -- they are easier to load and manage, have less overhead. locateLib :: Interp -> HscEnv -> Bool -> [FilePath] -> [FilePath] -> String -> IO LibrarySpec locateLib interp hsc_env is_hs lib_dirs gcc_dirs lib0 | not is_hs -- For non-Haskell libraries (e.g. gmp, iconv): -- first look in library-dirs for a dynamic library (on User paths only) -- (libfoo.so) -- then try looking for import libraries on Windows (on User paths only) -- (.dll.a, .lib) -- first look in library-dirs for a dynamic library (on GCC paths only) -- (libfoo.so) -- then check for system dynamic libraries (e.g. kernel32.dll on windows) -- then try looking for import libraries on Windows (on GCC paths only) -- (.dll.a, .lib) -- then look in library-dirs for a static library (libfoo.a) -- then look in library-dirs and inplace GCC for a dynamic library (libfoo.so) -- then try looking for import libraries on Windows (.dll.a, .lib) -- then look in library-dirs and inplace GCC for a static library (libfoo.a) -- then try "gcc --print-file-name" to search gcc's search path -- for a dynamic library (#5289) -- otherwise, assume loadDLL can find it -- -- The logic is a bit complicated, but the rationale behind it is that -- loading a shared library for us is O(1) while loading an archive is -- O(n). Loading an import library is also O(n) so in general we prefer -- shared libraries because they are simpler and faster. -- = #if defined(CAN_LOAD_DLL) findDll user `orElse` #endif tryImpLib user `orElse` #if defined(CAN_LOAD_DLL) findDll gcc `orElse` findSysDll `orElse` #endif tryImpLib gcc `orElse` findArchive `orElse` tryGcc `orElse` assumeDll | loading_dynamic_hs_libs -- search for .so libraries first. = findHSDll `orElse` findDynObject `orElse` assumeDll | otherwise -- use HSfoo.{o,p_o} if it exists, otherwise fallback to libHSfoo{,_p}.a = findObject `orElse` findArchive `orElse` assumeDll where dflags = hsc_dflags hsc_env logger = hsc_logger hsc_env diag_opts = initDiagOpts dflags dirs = lib_dirs ++ gcc_dirs gcc = False user = True -- Emulate ld's behavior of treating $LIB in `-l:$LIB` as a literal file -- name (lib, verbatim) = case lib0 of ':' : rest -> (rest, True) other -> (other, False) obj_file | is_hs && loading_profiled_hs_libs = lib <.> "p_o" | otherwise = lib <.> "o" dyn_obj_file = lib <.> "dyn_o" arch_files | verbatim = [lib] | otherwise = [ "lib" ++ lib ++ lib_tag <.> "a" , lib <.> "a" -- native code has no lib_tag , "lib" ++ lib , lib ] lib_tag = if is_hs && loading_profiled_hs_libs then "_p" else "" loading_profiled_hs_libs = interpreterProfiled interp loading_dynamic_hs_libs = interpreterDynamic interp import_libs | verbatim = [lib] | otherwise = [ lib <.> "lib" , "lib" ++ lib <.> "lib" , "lib" ++ lib <.> "dll.a" , lib <.> "dll.a" ] hs_dyn_lib_name = lib ++ dynLibSuffix (ghcNameVersion dflags) hs_dyn_lib_file = platformHsSOName platform hs_dyn_lib_name #if defined(CAN_LOAD_DLL) so_name = platformSOName platform lib lib_so_name = "lib" ++ so_name dyn_lib_file | verbatim && any (`isExtensionOf` lib) [".so", ".dylib", ".dll"] = lib | ArchX86_64 <- arch , OSSolaris2 <- os = "64" so_name | otherwise = so_name #endif findObject = liftM (fmap $ Objects . (:[])) $ findFile dirs obj_file findDynObject = liftM (fmap $ Objects . (:[])) $ findFile dirs dyn_obj_file findArchive = let local name = liftM (fmap Archive) $ findFile dirs name in apply (map local arch_files) findHSDll = liftM (fmap DLLPath) $ findFile dirs hs_dyn_lib_file #if defined(CAN_LOAD_DLL) findDll re = let dirs' = if re == user then lib_dirs else gcc_dirs in liftM (fmap DLLPath) $ findFile dirs' dyn_lib_file findSysDll = fmap (fmap $ DLL . dropExtension . takeFileName) $ findSystemLibrary interp so_name #endif tryGcc = let search = searchForLibUsingGcc logger dflags #if defined(CAN_LOAD_DLL) dllpath = liftM (fmap DLLPath) short = dllpath $ search so_name lib_dirs full = dllpath $ search lib_so_name lib_dirs dlls = [short, full] #endif gcc name = liftM (fmap Archive) $ search name lib_dirs files = import_libs ++ arch_files archives = map gcc files in apply $ #if defined(CAN_LOAD_DLL) dlls ++ #endif archives tryImpLib re = case os of OSMinGW32 -> let dirs' = if re == user then lib_dirs else gcc_dirs implib name = liftM (fmap Archive) $ findFile dirs' name in apply (map implib import_libs) _ -> return Nothing -- TH Makes use of the interpreter so this failure is not obvious. -- So we are nice and warn/inform users why we fail before we do. -- But only for haskell libraries, as C libraries don't have a -- profiling/non-profiling distinction to begin with. assumeDll | is_hs , not loading_dynamic_hs_libs , interpreterProfiled interp = do let diag = mkMCDiagnostic diag_opts WarningWithoutFlag logMsg logger diag noSrcSpan $ withPprStyle defaultErrStyle $ text "Interpreter failed to load profiled static library" <+> text lib <> char '.' $$ text " \tTrying dynamic library instead. If this fails try to rebuild" <+> text "libraries with profiling support." return (DLL lib) | otherwise = return (DLL lib) infixr `orElse` f `orElse` g = f >>= maybe g return apply :: [IO (Maybe a)] -> IO (Maybe a) apply [] = return Nothing apply (x:xs) = do x' <- x if isJust x' then return x' else apply xs platform = targetPlatform dflags #if defined(CAN_LOAD_DLL) arch = platformArch platform #endif os = platformOS platform searchForLibUsingGcc :: Logger -> DynFlags -> String -> [FilePath] -> IO (Maybe FilePath) searchForLibUsingGcc logger dflags so dirs = do -- GCC does not seem to extend the library search path (using -L) when using -- --print-file-name. So instead pass it a new base location. str <- askLd logger dflags (map (FileOption "-B") dirs ++ [Option "--print-file-name", Option so]) let file = case lines str of [] -> "" l:_ -> l if (file == so) then return Nothing else do b <- doesFileExist file -- file could be a folder (see #16063) return (if b then Just file else Nothing) -- | Retrieve the list of search directory GCC and the System use to find -- libraries and components. See Note [Fork/Exec Windows]. getGCCPaths :: Logger -> DynFlags -> OS -> IO [FilePath] getGCCPaths logger dflags os = case os of OSMinGW32 -> do gcc_dirs <- getGccSearchDirectory logger dflags "libraries" sys_dirs <- getSystemDirectories return $ nub $ gcc_dirs ++ sys_dirs _ -> return [] -- | Cache for the GCC search directories as this can't easily change -- during an invocation of GHC. (Maybe with some env. variable but we'll) -- deal with that highly unlikely scenario then. {-# NOINLINE gccSearchDirCache #-} gccSearchDirCache :: IORef [(String, [String])] gccSearchDirCache = unsafePerformIO $ newIORef [] -- Note [Fork/Exec Windows] -- ~~~~~~~~~~~~~~~~~~~~~~~~ -- fork/exec is expensive on Windows, for each time we ask GCC for a library we -- have to eat the cost of af least 3 of these: gcc -> real_gcc -> cc1. -- So instead get a list of location that GCC would search and use findDirs -- which hopefully is written in an optimized mannor to take advantage of -- caching. At the very least we remove the overhead of the fork/exec and waits -- which dominate a large percentage of startup time on Windows. getGccSearchDirectory :: Logger -> DynFlags -> String -> IO [FilePath] getGccSearchDirectory logger dflags key = do cache <- readIORef gccSearchDirCache case lookup key cache of Just x -> return x Nothing -> do str <- askLd logger dflags [Option "--print-search-dirs"] let line = dropWhile isSpace str name = key ++ ": =" if null line then return [] else do let val = split $ find name line dirs <- filterM doesDirectoryExist val modifyIORef' gccSearchDirCache ((key, dirs):) return val where split :: FilePath -> [FilePath] split r = case break (==';') r of (s, [] ) -> [s] (s, (_:xs)) -> s : split xs find :: String -> String -> String find r x = let lst = lines x val = filter (r `isPrefixOf`) lst in if null val then [] else case break (=='=') (head val) of (_ , []) -> [] (_, (_:xs)) -> xs -- | Get a list of system search directories, this to alleviate pressure on -- the findSysDll function. getSystemDirectories :: IO [FilePath] #if defined(mingw32_HOST_OS) getSystemDirectories = fmap (:[]) getSystemDirectory #else getSystemDirectories = return [] #endif -- | Merge the given list of paths with those in the environment variable -- given. If the variable does not exist then just return the identity. addEnvPaths :: String -> [String] -> IO [String] addEnvPaths name list = do -- According to POSIX (chapter 8.3) a zero-length prefix means current -- working directory. Replace empty strings in the env variable with -- `working_dir` (see also #14695). working_dir <- getCurrentDirectory values <- lookupEnv name case values of Nothing -> return list Just arr -> return $ list ++ splitEnv working_dir arr where splitEnv :: FilePath -> String -> [String] splitEnv working_dir value = case break (== envListSep) value of (x, [] ) -> [if null x then working_dir else x] (x, (_:xs)) -> (if null x then working_dir else x) : splitEnv working_dir xs #if defined(mingw32_HOST_OS) envListSep = ';' #else envListSep = ':' #endif -- ---------------------------------------------------------------------------- -- Loading a dynamic library (dlopen()-ish on Unix, LoadLibrary-ish on Win32) {- ********************************************************************** Helper functions ********************************************************************* -} maybePutSDoc :: Logger -> SDoc -> IO () maybePutSDoc logger s = when (logVerbAtLeast logger 2) $ logMsg logger MCInteractive noSrcSpan $ withPprStyle defaultUserStyle s maybePutStr :: Logger -> String -> IO () maybePutStr logger s = maybePutSDoc logger (text s) maybePutStrLn :: Logger -> String -> IO () maybePutStrLn logger s = maybePutSDoc logger (text s <> text "\n")