1 -- -----------------------------------------------------------------------------
3 -- (c) The University of Glasgow, 2005
7 -- -----------------------------------------------------------------------------
13 defaultCleanupHandler,
17 -- * Flags and settings
18 DynFlags(..), DynFlag(..), GhcMode(..), HscTarget(..), dopt,
26 Target(..), TargetId(..),
33 -- * Loading\/compiling the program
35 load, LoadHowMuch(..), SuccessFlag(..), -- also does depanal
37 workingDirectoryChanged,
38 checkModule, CheckedModule(..),
39 TypecheckedSource, ParsedSource, RenamedSource,
41 -- * Inspecting the module structure of the program
42 ModuleGraph, ModSummary(..),
47 -- * Inspecting modules
52 modInfoPrintUnqualified,
56 -- * Interactive evaluation
57 getBindings, getPrintUnqual,
59 setContext, getContext,
62 getInfo, GetInfoResult,
74 -- * Abstract syntax elements
77 Module, mkModule, pprModule,
84 isImplicitId, isDeadBinder,
85 isSpecPragmaId, isExportedId, isLocalId, isGlobalId,
87 isPrimOpId, isFCallId,
88 isDataConWorkId, idDataCon,
89 isBottomingId, isDictonaryId,
91 -- ** Type constructors
93 isClassTyCon, isSynTyCon, isNewTyCon,
95 -- ** Data constructors
100 classSCTheta, classTvsFds,
102 -- ** Types and Kinds
110 module HsSyn, -- ToDo: remove extraneous bits
113 GhcException(..), showGhcException,
123 * inline bits of HscMain here to simplify layering: hscGetInfo,
125 * we need to expose DynFlags, so should parseDynamicFlags really be
126 part of this interface?
127 * what StaticFlags should we expose, if any?
130 #include "HsVersions.h"
133 import qualified Linker
134 import Linker ( HValue, extendLinkEnv )
135 import NameEnv ( lookupNameEnv )
136 import TcRnDriver ( mkExportEnv, getModuleContents, tcRnLookupRdrName )
137 import RdrName ( plusGlobalRdrEnv )
138 import HscMain ( hscGetInfo, GetInfoResult, hscParseIdentifier,
139 hscStmt, hscTcExpr, hscKcType )
140 import Type ( tidyType )
141 import VarEnv ( emptyTidyEnv )
142 import GHC.Exts ( unsafeCoerce# )
143 import IfaceSyn ( IfaceDecl )
146 import Packages ( initPackages )
147 import NameSet ( NameSet, nameSetToList )
148 import RdrName ( GlobalRdrEnv )
150 import Type ( Kind, Type, dropForAlls )
151 import Id ( Id, idType, isImplicitId, isDeadBinder,
152 isSpecPragmaId, isExportedId, isLocalId, isGlobalId,
154 isPrimOpId, isFCallId,
155 isDataConWorkId, idDataCon,
157 import TyCon ( TyCon, isClassTyCon, isSynTyCon, isNewTyCon )
158 import Class ( Class, classSCTheta, classTvsFds )
159 import DataCon ( DataCon )
160 import InstEnv ( Instance )
161 import Name ( Name, getName, nameModule_maybe )
162 import RdrName ( RdrName, gre_name, globalRdrEnvElts )
163 import NameEnv ( nameEnvElts )
164 import SrcLoc ( Located(..), mkSrcLoc, srcLocSpan )
165 import DriverPipeline
166 import DriverPhases ( Phase(..), isHaskellSrcFilename, startPhase )
167 import GetImports ( getImports )
168 import Packages ( isHomePackage )
170 import HscMain ( newHscEnv, hscFileCheck, HscResult(..) )
174 import SysTools ( initSysTools, cleanTempFiles )
179 import ErrUtils ( showPass, Messages, putMsg, debugTraceMsg )
180 import qualified ErrUtils
182 import StringBuffer ( StringBuffer, hGetStringBuffer )
184 import SysTools ( cleanTempFilesExcept )
185 import BasicTypes ( SuccessFlag(..), succeeded, failed )
186 import Maybes ( orElse, expectJust, mapCatMaybes )
187 import TcType ( tcSplitSigmaTy, isDictTy )
188 import Bag ( unitBag, emptyBag )
189 import FastString ( mkFastString )
191 import Directory ( getModificationTime, doesFileExist )
192 import Maybe ( isJust, isNothing, fromJust, fromMaybe, catMaybes )
193 import Maybes ( expectJust )
194 import List ( partition, nub )
195 import qualified List
196 import Monad ( unless, when, foldM )
197 import System ( exitWith, ExitCode(..) )
198 import Time ( ClockTime )
199 import EXCEPTION as Exception hiding (handle)
202 import Prelude hiding (init)
204 -- -----------------------------------------------------------------------------
205 -- Exception handlers
207 -- | Install some default exception handlers and run the inner computation.
208 -- Unless you want to handle exceptions yourself, you should wrap this around
209 -- the top level of your program. The default handlers output the error
210 -- message(s) to stderr and exit cleanly.
211 defaultErrorHandler :: IO a -> IO a
212 defaultErrorHandler inner =
213 -- top-level exception handler: any unrecognised exception is a compiler bug.
214 handle (\exception -> do
217 -- an IO exception probably isn't our fault, so don't panic
218 IOException _ -> putMsg (show exception)
219 AsyncException StackOverflow ->
220 putMsg "stack overflow: use +RTS -K<size> to increase it"
221 _other -> putMsg (show (Panic (show exception)))
222 exitWith (ExitFailure 1)
225 -- all error messages are propagated as exceptions
226 handleDyn (\dyn -> do
229 PhaseFailed _ code -> exitWith code
230 Interrupted -> exitWith (ExitFailure 1)
231 _ -> do putMsg (show (dyn :: GhcException))
232 exitWith (ExitFailure 1)
236 -- | Install a default cleanup handler to remove temporary files
237 -- deposited by a GHC run. This is seperate from
238 -- 'defaultErrorHandler', because you might want to override the error
239 -- handling, but still get the ordinary cleanup behaviour.
240 defaultCleanupHandler :: DynFlags -> IO a -> IO a
241 defaultCleanupHandler dflags inner =
242 -- make sure we clean up after ourselves
243 later (unless (dopt Opt_KeepTmpFiles dflags) $
244 cleanTempFiles dflags)
245 -- exceptions will be blocked while we clean the temporary files,
246 -- so there shouldn't be any difficulty if we receive further
251 -- | Initialises GHC. This must be done /once/ only. Takes the
252 -- command-line arguments. All command-line arguments which aren't
253 -- understood by GHC will be returned.
255 init :: [String] -> IO [String]
258 installSignalHandlers
260 -- Grab the -B option if there is one
261 let (minusB_args, argv1) = partition (prefixMatch "-B") args
262 dflags0 <- initSysTools minusB_args defaultDynFlags
263 writeIORef v_initDynFlags dflags0
265 -- Parse the static flags
266 argv2 <- parseStaticFlags argv1
269 GLOBAL_VAR(v_initDynFlags, error "initDynFlags", DynFlags)
270 -- stores the DynFlags between the call to init and subsequent
271 -- calls to newSession.
273 -- | Starts a new session. A session consists of a set of loaded
274 -- modules, a set of options (DynFlags), and an interactive context.
275 -- ToDo: GhcMode should say "keep typechecked code" and\/or "keep renamed
277 newSession :: GhcMode -> IO Session
279 dflags0 <- readIORef v_initDynFlags
280 dflags <- initDynFlags dflags0
281 env <- newHscEnv dflags{ ghcMode=mode }
285 -- tmp: this breaks the abstraction, but required because DriverMkDepend
286 -- needs to call the Finder. ToDo: untangle this.
287 sessionHscEnv :: Session -> IO HscEnv
288 sessionHscEnv (Session ref) = readIORef ref
290 withSession :: Session -> (HscEnv -> IO a) -> IO a
291 withSession (Session ref) f = do h <- readIORef ref; f h
293 modifySession :: Session -> (HscEnv -> HscEnv) -> IO ()
294 modifySession (Session ref) f = do h <- readIORef ref; writeIORef ref $! f h
296 -- -----------------------------------------------------------------------------
299 -- | Grabs the DynFlags from the Session
300 getSessionDynFlags :: Session -> IO DynFlags
301 getSessionDynFlags s = withSession s (return . hsc_dflags)
303 -- | Updates the DynFlags in a Session
304 setSessionDynFlags :: Session -> DynFlags -> IO ()
305 setSessionDynFlags s dflags = modifySession s (\h -> h{ hsc_dflags = dflags })
307 -- | Messages during compilation (eg. warnings and progress messages)
308 -- are reported using this callback. By default, these messages are
309 -- printed to stderr.
310 setMsgHandler :: (String -> IO ()) -> IO ()
311 setMsgHandler = ErrUtils.setMsgHandler
313 -- -----------------------------------------------------------------------------
316 -- ToDo: think about relative vs. absolute file paths. And what
317 -- happens when the current directory changes.
319 -- | Sets the targets for this session. Each target may be a module name
320 -- or a filename. The targets correspond to the set of root modules for
321 -- the program\/library. Unloading the current program is achieved by
322 -- setting the current set of targets to be empty, followed by load.
323 setTargets :: Session -> [Target] -> IO ()
324 setTargets s targets = modifySession s (\h -> h{ hsc_targets = targets })
326 -- | returns the current set of targets
327 getTargets :: Session -> IO [Target]
328 getTargets s = withSession s (return . hsc_targets)
330 -- | Add another target
331 addTarget :: Session -> Target -> IO ()
333 = modifySession s (\h -> h{ hsc_targets = target : hsc_targets h })
336 removeTarget :: Session -> TargetId -> IO ()
337 removeTarget s target_id
338 = modifySession s (\h -> h{ hsc_targets = filter (hsc_targets h) })
340 filter targets = [ t | t@(Target id _) <- targets, id /= target_id ]
342 -- Attempts to guess what Target a string refers to. This function implements
343 -- the --make/GHCi command-line syntax for filenames:
345 -- - if the string looks like a Haskell source filename, then interpret
347 -- - if adding a .hs or .lhs suffix yields the name of an existing file,
349 -- - otherwise interpret the string as a module name
351 guessTarget :: String -> IO Target
353 | isHaskellSrcFilename file
354 = return (Target (TargetFile file) Nothing)
356 = do exists <- doesFileExist hs_file
357 if exists then return (Target (TargetFile hs_file) Nothing) else do
358 exists <- doesFileExist lhs_file
359 if exists then return (Target (TargetFile lhs_file) Nothing) else do
360 return (Target (TargetModule (mkModule file)) Nothing)
362 hs_file = file ++ ".hs"
363 lhs_file = file ++ ".lhs"
365 -- -----------------------------------------------------------------------------
366 -- Loading the program
368 -- Perform a dependency analysis starting from the current targets
369 -- and update the session with the new module graph.
370 depanal :: Session -> [Module] -> IO ()
371 depanal (Session ref) excluded_mods = do
372 hsc_env <- readIORef ref
374 dflags = hsc_dflags hsc_env
375 gmode = ghcMode (hsc_dflags hsc_env)
376 targets = hsc_targets hsc_env
377 old_graph = hsc_mod_graph hsc_env
379 showPass dflags "Chasing dependencies"
380 when (gmode == BatchCompile) $
381 debugTraceMsg dflags 1 (showSDoc (hcat [
382 text "Chasing modules from: ",
383 hcat (punctuate comma (map pprTarget targets))]))
385 graph <- downsweep hsc_env old_graph excluded_mods
386 writeIORef ref hsc_env{ hsc_mod_graph=graph }
389 -- | The result of load.
391 = LoadOk Errors -- ^ all specified targets were loaded successfully.
392 | LoadFailed Errors -- ^ not all modules were loaded.
394 type Errors = [String]
396 data ErrMsg = ErrMsg {
397 errMsgSeverity :: Severity, -- warning, error, etc.
398 errMsgSpans :: [SrcSpan],
399 errMsgShortDoc :: Doc,
400 errMsgExtraInfo :: Doc
407 | LoadDependenciesOf Module
409 -- | Try to load the program. If a Module is supplied, then just
410 -- attempt to load up to this target. If no Module is supplied,
411 -- then try to load all targets.
412 load :: Session -> LoadHowMuch -> IO SuccessFlag
413 load session how_much =
414 loadMsgs session how_much ErrUtils.printErrorsAndWarnings
416 -- | Version of 'load' that takes a callback function to be invoked
417 -- on compiler errors and warnings as they occur during compilation.
418 loadMsgs :: Session -> LoadHowMuch -> (Messages-> IO ()) -> IO SuccessFlag
419 loadMsgs s@(Session ref) how_much msg_act
421 -- Dependency analysis first. Note that this fixes the module graph:
422 -- even if we don't get a fully successful upsweep, the full module
423 -- graph is still retained in the Session. We can tell which modules
424 -- were successfully loaded by inspecting the Session's HPT.
427 hsc_env <- readIORef ref
429 let hpt1 = hsc_HPT hsc_env
430 let dflags = hsc_dflags hsc_env
431 let mod_graph = hsc_mod_graph hsc_env
433 let ghci_mode = ghcMode (hsc_dflags hsc_env) -- this never changes
434 let verb = verbosity dflags
436 -- The "bad" boot modules are the ones for which we have
437 -- B.hs-boot in the module graph, but no B.hs
438 -- The downsweep should have ensured this does not happen
440 let all_home_mods = [ms_mod s | s <- mod_graph, not (isBootSummary s)]
441 bad_boot_mods = [s | s <- mod_graph, isBootSummary s,
442 not (ms_mod s `elem` all_home_mods)]
443 ASSERT( null bad_boot_mods ) return ()
445 -- mg2_with_srcimps drops the hi-boot nodes, returning a
446 -- graph with cycles. Among other things, it is used for
447 -- backing out partially complete cycles following a failed
448 -- upsweep, and for removing from hpt all the modules
449 -- not in strict downwards closure, during calls to compile.
450 let mg2_with_srcimps :: [SCC ModSummary]
451 mg2_with_srcimps = topSortModuleGraph True mod_graph Nothing
453 -- check the stability property for each module.
454 stable_mods@(stable_obj,stable_bco)
455 | BatchCompile <- ghci_mode = ([],[])
456 | otherwise = checkStability hpt1 mg2_with_srcimps all_home_mods
458 -- prune bits of the HPT which are definitely redundant now,
460 pruned_hpt = pruneHomePackageTable hpt1
461 (flattenSCCs mg2_with_srcimps)
466 debugTraceMsg dflags 2 (showSDoc (text "Stable obj:" <+> ppr stable_obj $$
467 text "Stable BCO:" <+> ppr stable_bco))
469 -- Unload any modules which are going to be re-linked this time around.
470 let stable_linkables = [ linkable
471 | m <- stable_obj++stable_bco,
472 Just hmi <- [lookupModuleEnv pruned_hpt m],
473 Just linkable <- [hm_linkable hmi] ]
474 unload hsc_env stable_linkables
476 -- We could at this point detect cycles which aren't broken by
477 -- a source-import, and complain immediately, but it seems better
478 -- to let upsweep_mods do this, so at least some useful work gets
479 -- done before the upsweep is abandoned.
480 --hPutStrLn stderr "after tsort:\n"
481 --hPutStrLn stderr (showSDoc (vcat (map ppr mg2)))
483 -- Now do the upsweep, calling compile for each module in
484 -- turn. Final result is version 3 of everything.
486 -- Topologically sort the module graph, this time including hi-boot
487 -- nodes, and possibly just including the portion of the graph
488 -- reachable from the module specified in the 2nd argument to load.
489 -- This graph should be cycle-free.
490 -- If we're restricting the upsweep to a portion of the graph, we
491 -- also want to retain everything that is still stable.
492 let full_mg :: [SCC ModSummary]
493 full_mg = topSortModuleGraph False mod_graph Nothing
495 maybe_top_mod = case how_much of
497 LoadDependenciesOf m -> Just m
500 partial_mg0 :: [SCC ModSummary]
501 partial_mg0 = topSortModuleGraph False mod_graph maybe_top_mod
503 -- LoadDependenciesOf m: we want the upsweep to stop just
504 -- short of the specified module (unless the specified module
507 | LoadDependenciesOf mod <- how_much
508 = ASSERT( case last partial_mg0 of
509 AcyclicSCC ms -> ms_mod ms == mod; _ -> False )
510 List.init partial_mg0
516 | AcyclicSCC ms <- full_mg,
517 ms_mod ms `elem` stable_obj++stable_bco,
518 ms_mod ms `notElem` [ ms_mod ms' |
519 AcyclicSCC ms' <- partial_mg ] ]
521 mg = stable_mg ++ partial_mg
523 -- clean up between compilations
524 let cleanup = cleanTempFilesExcept dflags
525 (ppFilesFromSummaries (flattenSCCs mg2_with_srcimps))
527 (upsweep_ok, hsc_env1, modsUpswept)
528 <- upsweep (hsc_env { hsc_HPT = emptyHomePackageTable })
529 pruned_hpt stable_mods cleanup msg_act mg
531 -- Make modsDone be the summaries for each home module now
532 -- available; this should equal the domain of hpt3.
533 -- Get in in a roughly top .. bottom order (hence reverse).
535 let modsDone = reverse modsUpswept
537 -- Try and do linking in some form, depending on whether the
538 -- upsweep was completely or only partially successful.
540 if succeeded upsweep_ok
543 -- Easy; just relink it all.
544 do debugTraceMsg dflags 2 "Upsweep completely successful."
546 -- Clean up after ourselves
547 cleanTempFilesExcept dflags (ppFilesFromSummaries modsDone)
549 -- Issue a warning for the confusing case where the user
550 -- said '-o foo' but we're not going to do any linking.
551 -- We attempt linking if either (a) one of the modules is
552 -- called Main, or (b) the user said -no-hs-main, indicating
553 -- that main() is going to come from somewhere else.
555 let ofile = outputFile dflags
556 let no_hs_main = dopt Opt_NoHsMain dflags
557 let mb_main_mod = mainModIs dflags
559 main_mod = mb_main_mod `orElse` "Main"
561 = any ((==main_mod).moduleUserString.ms_mod)
563 do_linking = a_root_is_Main || no_hs_main
565 when (ghci_mode == BatchCompile && isJust ofile && not do_linking) $
566 debugTraceMsg dflags 1 ("Warning: output was redirected with -o, " ++
567 "but no output will be generated\n" ++
568 "because there is no " ++ main_mod ++ " module.")
570 -- link everything together
571 linkresult <- link ghci_mode dflags do_linking (hsc_HPT hsc_env1)
573 loadFinish Succeeded linkresult ref hsc_env1
576 -- Tricky. We need to back out the effects of compiling any
577 -- half-done cycles, both so as to clean up the top level envs
578 -- and to avoid telling the interactive linker to link them.
579 do debugTraceMsg dflags 2 "Upsweep partially successful."
582 = map ms_mod modsDone
583 let mods_to_zap_names
584 = findPartiallyCompletedCycles modsDone_names
587 = filter ((`notElem` mods_to_zap_names).ms_mod)
590 let hpt4 = retainInTopLevelEnvs (map ms_mod mods_to_keep)
593 -- Clean up after ourselves
594 cleanTempFilesExcept dflags (ppFilesFromSummaries mods_to_keep)
596 -- there should be no Nothings where linkables should be, now
597 ASSERT(all (isJust.hm_linkable)
598 (moduleEnvElts (hsc_HPT hsc_env))) do
600 -- Link everything together
601 linkresult <- link ghci_mode dflags False hpt4
603 let hsc_env4 = hsc_env1{ hsc_HPT = hpt4 }
604 loadFinish Failed linkresult ref hsc_env4
606 -- Finish up after a load.
608 -- If the link failed, unload everything and return.
609 loadFinish all_ok Failed ref hsc_env
610 = do unload hsc_env []
611 writeIORef ref $! discardProg hsc_env
614 -- Empty the interactive context and set the module context to the topmost
615 -- newly loaded module, or the Prelude if none were loaded.
616 loadFinish all_ok Succeeded ref hsc_env
617 = do writeIORef ref $! hsc_env{ hsc_IC = emptyInteractiveContext }
621 -- Forget the current program, but retain the persistent info in HscEnv
622 discardProg :: HscEnv -> HscEnv
624 = hsc_env { hsc_mod_graph = emptyMG,
625 hsc_IC = emptyInteractiveContext,
626 hsc_HPT = emptyHomePackageTable }
628 -- used to fish out the preprocess output files for the purposes of
629 -- cleaning up. The preprocessed file *might* be the same as the
630 -- source file, but that doesn't do any harm.
631 ppFilesFromSummaries summaries = [ fn | Just fn <- map ms_hspp_file summaries ]
633 -- -----------------------------------------------------------------------------
637 CheckedModule { parsedSource :: ParsedSource,
638 renamedSource :: Maybe RenamedSource,
639 typecheckedSource :: Maybe TypecheckedSource,
640 checkedModuleInfo :: Maybe ModuleInfo
643 type ParsedSource = Located (HsModule RdrName)
644 type RenamedSource = HsGroup Name
645 type TypecheckedSource = LHsBinds Id
647 -- | This is the way to get access to parsed and typechecked source code
648 -- for a module. 'checkModule' loads all the dependencies of the specified
649 -- module in the Session, and then attempts to typecheck the module. If
650 -- successful, it returns the abstract syntax for the module.
651 checkModule :: Session -> Module -> (Messages -> IO ())
652 -> IO (Maybe CheckedModule)
653 checkModule session@(Session ref) mod msg_act = do
654 -- load up the dependencies first
655 r <- loadMsgs session (LoadDependenciesOf mod) msg_act
656 if (failed r) then return Nothing else do
658 -- now parse & typecheck the module
659 hsc_env <- readIORef ref
660 let mg = hsc_mod_graph hsc_env
661 case [ ms | ms <- mg, ms_mod ms == mod ] of
664 -- Add in the OPTIONS from the source file This is nasty:
665 -- we've done this once already, in the compilation manager
666 -- It might be better to cache the flags in the
667 -- ml_hspp_file field, say
668 let dflags0 = hsc_dflags hsc_env
669 hspp_buf = expectJust "GHC.checkModule" (ms_hspp_buf ms)
670 opts = getOptionsFromStringBuffer hspp_buf
671 (dflags1,leftovers) <- parseDynamicFlags dflags0 (map snd opts)
672 if (not (null leftovers))
673 then do let filename = fromJust (ml_hs_file (ms_location ms))
674 msg_act (optionsErrorMsgs leftovers opts filename)
678 r <- hscFileCheck hsc_env{hsc_dflags=dflags1} msg_act ms
682 HscChecked parsed renamed Nothing ->
683 return (Just (CheckedModule {
684 parsedSource = parsed,
685 renamedSource = renamed,
686 typecheckedSource = Nothing,
687 checkedModuleInfo = Nothing }))
688 HscChecked parsed renamed
689 (Just (tc_binds, rdr_env, details)) -> do
690 let minf = ModuleInfo {
691 minf_details = details,
692 minf_rdr_env = Just rdr_env
694 return (Just (CheckedModule {
695 parsedSource = parsed,
696 renamedSource = renamed,
697 typecheckedSource = Just tc_binds,
698 checkedModuleInfo = Just minf }))
700 -- ---------------------------------------------------------------------------
703 unload :: HscEnv -> [Linkable] -> IO ()
704 unload hsc_env stable_linkables -- Unload everthing *except* 'stable_linkables'
705 = case ghcMode (hsc_dflags hsc_env) of
706 BatchCompile -> return ()
707 JustTypecheck -> return ()
709 Interactive -> Linker.unload (hsc_dflags hsc_env) stable_linkables
711 Interactive -> panic "unload: no interpreter"
713 other -> panic "unload: strange mode"
715 -- -----------------------------------------------------------------------------
719 Stability tells us which modules definitely do not need to be recompiled.
720 There are two main reasons for having stability:
722 - avoid doing a complete upsweep of the module graph in GHCi when
723 modules near the bottom of the tree have not changed.
725 - to tell GHCi when it can load object code: we can only load object code
726 for a module when we also load object code fo all of the imports of the
727 module. So we need to know that we will definitely not be recompiling
728 any of these modules, and we can use the object code.
730 NB. stability is of no importance to BatchCompile at all, only Interactive.
731 (ToDo: what about JustTypecheck?)
733 The stability check is as follows. Both stableObject and
734 stableBCO are used during the upsweep phase later.
737 stable m = stableObject m || stableBCO m
740 all stableObject (imports m)
741 && old linkable does not exist, or is == on-disk .o
742 && date(on-disk .o) > date(.hs)
745 all stable (imports m)
746 && date(BCO) > date(.hs)
749 These properties embody the following ideas:
751 - if a module is stable:
752 - if it has been compiled in a previous pass (present in HPT)
753 then it does not need to be compiled or re-linked.
754 - if it has not been compiled in a previous pass,
755 then we only need to read its .hi file from disk and
756 link it to produce a ModDetails.
758 - if a modules is not stable, we will definitely be at least
759 re-linking, and possibly re-compiling it during the upsweep.
760 All non-stable modules can (and should) therefore be unlinked
763 - Note that objects are only considered stable if they only depend
764 on other objects. We can't link object code against byte code.
768 :: HomePackageTable -- HPT from last compilation
769 -> [SCC ModSummary] -- current module graph (cyclic)
770 -> [Module] -- all home modules
771 -> ([Module], -- stableObject
772 [Module]) -- stableBCO
774 checkStability hpt sccs all_home_mods = foldl checkSCC ([],[]) sccs
776 checkSCC (stable_obj, stable_bco) scc0
777 | stableObjects = (scc_mods ++ stable_obj, stable_bco)
778 | stableBCOs = (stable_obj, scc_mods ++ stable_bco)
779 | otherwise = (stable_obj, stable_bco)
781 scc = flattenSCC scc0
782 scc_mods = map ms_mod scc
783 home_module m = m `elem` all_home_mods && m `notElem` scc_mods
785 scc_allimps = nub (filter home_module (concatMap ms_allimps scc))
786 -- all imports outside the current SCC, but in the home pkg
788 stable_obj_imps = map (`elem` stable_obj) scc_allimps
789 stable_bco_imps = map (`elem` stable_bco) scc_allimps
796 and (zipWith (||) stable_obj_imps stable_bco_imps)
800 | Just t <- ms_obj_date ms = t >= ms_hs_date ms
804 same_as_prev t = case lookupModuleEnv hpt (ms_mod ms) of
806 Just hmi | Just l <- hm_linkable hmi
807 -> isObjectLinkable l && t == linkableTime l
808 -- why '>=' rather than '>' above? If the filesystem stores
809 -- times to the nearset second, we may occasionally find that
810 -- the object & source have the same modification time,
811 -- especially if the source was automatically generated
812 -- and compiled. Using >= is slightly unsafe, but it matches
816 = case lookupModuleEnv hpt (ms_mod ms) of
818 Just hmi | Just l <- hm_linkable hmi ->
819 not (isObjectLinkable l) &&
820 linkableTime l >= ms_hs_date ms
822 ms_allimps :: ModSummary -> [Module]
823 ms_allimps ms = ms_srcimps ms ++ ms_imps ms
825 -- -----------------------------------------------------------------------------
826 -- Prune the HomePackageTable
828 -- Before doing an upsweep, we can throw away:
830 -- - For non-stable modules:
831 -- - all ModDetails, all linked code
832 -- - all unlinked code that is out of date with respect to
835 -- This is VERY IMPORTANT otherwise we'll end up requiring 2x the
836 -- space at the end of the upsweep, because the topmost ModDetails of the
837 -- old HPT holds on to the entire type environment from the previous
840 pruneHomePackageTable
843 -> ([Module],[Module])
846 pruneHomePackageTable hpt summ (stable_obj, stable_bco)
847 = mapModuleEnv prune hpt
849 | is_stable modl = hmi'
850 | otherwise = hmi'{ hm_details = emptyModDetails }
852 modl = mi_module (hm_iface hmi)
853 hmi' | Just l <- hm_linkable hmi, linkableTime l < ms_hs_date ms
854 = hmi{ hm_linkable = Nothing }
857 where ms = expectJust "prune" (lookupModuleEnv ms_map modl)
859 ms_map = mkModuleEnv [(ms_mod ms, ms) | ms <- summ]
861 is_stable m = m `elem` stable_obj || m `elem` stable_bco
863 -- -----------------------------------------------------------------------------
865 -- Return (names of) all those in modsDone who are part of a cycle
866 -- as defined by theGraph.
867 findPartiallyCompletedCycles :: [Module] -> [SCC ModSummary] -> [Module]
868 findPartiallyCompletedCycles modsDone theGraph
872 chew ((AcyclicSCC v):rest) = chew rest -- acyclic? not interesting.
873 chew ((CyclicSCC vs):rest)
874 = let names_in_this_cycle = nub (map ms_mod vs)
876 = nub ([done | done <- modsDone,
877 done `elem` names_in_this_cycle])
878 chewed_rest = chew rest
880 if notNull mods_in_this_cycle
881 && length mods_in_this_cycle < length names_in_this_cycle
882 then mods_in_this_cycle ++ chewed_rest
885 -- -----------------------------------------------------------------------------
888 -- This is where we compile each module in the module graph, in a pass
889 -- from the bottom to the top of the graph.
891 -- There better had not be any cyclic groups here -- we check for them.
894 :: HscEnv -- Includes initially-empty HPT
895 -> HomePackageTable -- HPT from last time round (pruned)
896 -> ([Module],[Module]) -- stable modules (see checkStability)
897 -> IO () -- How to clean up unwanted tmp files
898 -> (Messages -> IO ()) -- Compiler error message callback
899 -> [SCC ModSummary] -- Mods to do (the worklist)
901 HscEnv, -- With an updated HPT
902 [ModSummary]) -- Mods which succeeded
904 upsweep hsc_env old_hpt stable_mods cleanup msg_act mods
905 = upsweep' hsc_env old_hpt stable_mods cleanup msg_act mods 1 (length mods)
907 upsweep' hsc_env old_hpt stable_mods cleanup msg_act
909 = return (Succeeded, hsc_env, [])
911 upsweep' hsc_env old_hpt stable_mods cleanup msg_act
913 = do putMsg (showSDoc (cyclicModuleErr ms))
914 return (Failed, hsc_env, [])
916 upsweep' hsc_env old_hpt stable_mods cleanup msg_act
917 (AcyclicSCC mod:mods) mod_index nmods
918 = do -- putStrLn ("UPSWEEP_MOD: hpt = " ++
919 -- show (map (moduleUserString.moduleName.mi_module.hm_iface)
920 -- (moduleEnvElts (hsc_HPT hsc_env)))
922 mb_mod_info <- upsweep_mod hsc_env old_hpt stable_mods msg_act mod
925 cleanup -- Remove unwanted tmp files between compilations
928 Nothing -> return (Failed, hsc_env, [])
930 { let this_mod = ms_mod mod
932 -- Add new info to hsc_env
933 hpt1 = extendModuleEnv (hsc_HPT hsc_env)
935 hsc_env1 = hsc_env { hsc_HPT = hpt1 }
937 -- Space-saving: delete the old HPT entry
938 -- for mod BUT if mod is a hs-boot
939 -- node, don't delete it. For the
940 -- interface, the HPT entry is probaby for the
941 -- main Haskell source file. Deleting it
942 -- would force .. (what?? --SDM)
943 old_hpt1 | isBootSummary mod = old_hpt
944 | otherwise = delModuleEnv old_hpt this_mod
946 ; (restOK, hsc_env2, modOKs)
947 <- upsweep' hsc_env1 old_hpt1 stable_mods cleanup
948 msg_act mods (mod_index+1) nmods
949 ; return (restOK, hsc_env2, mod:modOKs)
953 -- Compile a single module. Always produce a Linkable for it if
954 -- successful. If no compilation happened, return the old Linkable.
955 upsweep_mod :: HscEnv
957 -> ([Module],[Module])
958 -> (Messages -> IO ())
960 -> Int -- index of module
961 -> Int -- total number of modules
962 -> IO (Maybe HomeModInfo) -- Nothing => Failed
964 upsweep_mod hsc_env old_hpt (stable_obj, stable_bco) msg_act summary mod_index nmods
967 this_mod = ms_mod summary
968 mb_obj_date = ms_obj_date summary
969 obj_fn = ml_obj_file (ms_location summary)
970 hs_date = ms_hs_date summary
972 compile_it :: Maybe Linkable -> IO (Maybe HomeModInfo)
973 compile_it = upsweep_compile hsc_env old_hpt this_mod
974 msg_act summary mod_index nmods
976 case ghcMode (hsc_dflags hsc_env) of
979 -- Batch-compilating is easy: just check whether we have
980 -- an up-to-date object file. If we do, then the compiler
981 -- needs to do a recompilation check.
982 _ | Just obj_date <- mb_obj_date, obj_date >= hs_date -> do
984 findObjectLinkable this_mod obj_fn obj_date
985 compile_it (Just linkable)
992 _ | is_stable_obj, isJust old_hmi ->
994 -- object is stable, and we have an entry in the
995 -- old HPT: nothing to do
997 | is_stable_obj, isNothing old_hmi -> do
999 findObjectLinkable this_mod obj_fn
1000 (expectJust "upseep1" mb_obj_date)
1001 compile_it (Just linkable)
1002 -- object is stable, but we need to load the interface
1003 -- off disk to make a HMI.
1006 ASSERT(isJust old_hmi) -- must be in the old_hpt
1008 -- BCO is stable: nothing to do
1010 | Just hmi <- old_hmi,
1011 Just l <- hm_linkable hmi, not (isObjectLinkable l),
1012 linkableTime l >= ms_hs_date summary ->
1014 -- we have an old BCO that is up to date with respect
1015 -- to the source: do a recompilation check as normal.
1019 -- no existing code at all: we must recompile.
1021 is_stable_obj = this_mod `elem` stable_obj
1022 is_stable_bco = this_mod `elem` stable_bco
1024 old_hmi = lookupModuleEnv old_hpt this_mod
1026 -- Run hsc to compile a module
1027 upsweep_compile hsc_env old_hpt this_mod msg_act summary
1029 mb_old_linkable = do
1031 -- The old interface is ok if it's in the old HPT
1032 -- a) we're compiling a source file, and the old HPT
1033 -- entry is for a source file
1034 -- b) we're compiling a hs-boot file
1035 -- Case (b) allows an hs-boot file to get the interface of its
1036 -- real source file on the second iteration of the compilation
1037 -- manager, but that does no harm. Otherwise the hs-boot file
1038 -- will always be recompiled
1041 = case lookupModuleEnv old_hpt this_mod of
1043 Just hm_info | isBootSummary summary -> Just iface
1044 | not (mi_boot iface) -> Just iface
1045 | otherwise -> Nothing
1047 iface = hm_iface hm_info
1049 compresult <- compile hsc_env msg_act summary mb_old_linkable mb_old_iface
1053 -- Compilation failed. Compile may still have updated the PCS, tho.
1054 CompErrs -> return Nothing
1056 -- Compilation "succeeded", and may or may not have returned a new
1057 -- linkable (depending on whether compilation was actually performed
1059 CompOK new_details new_iface new_linkable
1060 -> do let new_info = HomeModInfo { hm_iface = new_iface,
1061 hm_details = new_details,
1062 hm_linkable = new_linkable }
1063 return (Just new_info)
1066 -- Filter modules in the HPT
1067 retainInTopLevelEnvs :: [Module] -> HomePackageTable -> HomePackageTable
1068 retainInTopLevelEnvs keep_these hpt
1069 = mkModuleEnv [ (mod, expectJust "retain" mb_mod_info)
1071 , let mb_mod_info = lookupModuleEnv hpt mod
1072 , isJust mb_mod_info ]
1074 -- ---------------------------------------------------------------------------
1075 -- Topological sort of the module graph
1078 :: Bool -- Drop hi-boot nodes? (see below)
1082 -- Calculate SCCs of the module graph, possibly dropping the hi-boot nodes
1083 -- The resulting list of strongly-connected-components is in topologically
1084 -- sorted order, starting with the module(s) at the bottom of the
1085 -- dependency graph (ie compile them first) and ending with the ones at
1088 -- Drop hi-boot nodes (first boolean arg)?
1090 -- False: treat the hi-boot summaries as nodes of the graph,
1091 -- so the graph must be acyclic
1093 -- True: eliminate the hi-boot nodes, and instead pretend
1094 -- the a source-import of Foo is an import of Foo
1095 -- The resulting graph has no hi-boot nodes, but can by cyclic
1097 topSortModuleGraph drop_hs_boot_nodes summaries Nothing
1098 = stronglyConnComp (fst (moduleGraphNodes drop_hs_boot_nodes summaries))
1099 topSortModuleGraph drop_hs_boot_nodes summaries (Just mod)
1100 = stronglyConnComp (map vertex_fn (reachable graph root))
1102 -- restrict the graph to just those modules reachable from
1103 -- the specified module. We do this by building a graph with
1104 -- the full set of nodes, and determining the reachable set from
1105 -- the specified node.
1106 (nodes, lookup_key) = moduleGraphNodes drop_hs_boot_nodes summaries
1107 (graph, vertex_fn, key_fn) = graphFromEdges' nodes
1109 | Just key <- lookup_key HsSrcFile mod, Just v <- key_fn key = v
1110 | otherwise = throwDyn (ProgramError "module does not exist")
1112 moduleGraphNodes :: Bool -> [ModSummary]
1113 -> ([(ModSummary, Int, [Int])], HscSource -> Module -> Maybe Int)
1114 moduleGraphNodes drop_hs_boot_nodes summaries = (nodes, lookup_key)
1116 -- Drop hs-boot nodes by using HsSrcFile as the key
1117 hs_boot_key | drop_hs_boot_nodes = HsSrcFile
1118 | otherwise = HsBootFile
1120 -- We use integers as the keys for the SCC algorithm
1121 nodes :: [(ModSummary, Int, [Int])]
1122 nodes = [(s, expectJust "topSort" (lookup_key (ms_hsc_src s) (ms_mod s)),
1123 out_edge_keys hs_boot_key (ms_srcimps s) ++
1124 out_edge_keys HsSrcFile (ms_imps s) )
1126 , not (isBootSummary s && drop_hs_boot_nodes) ]
1127 -- Drop the hi-boot ones if told to do so
1129 key_map :: NodeMap Int
1130 key_map = listToFM ([(ms_mod s, ms_hsc_src s) | s <- summaries]
1133 lookup_key :: HscSource -> Module -> Maybe Int
1134 lookup_key hs_src mod = lookupFM key_map (mod, hs_src)
1136 out_edge_keys :: HscSource -> [Module] -> [Int]
1137 out_edge_keys hi_boot ms = mapCatMaybes (lookup_key hi_boot) ms
1138 -- If we want keep_hi_boot_nodes, then we do lookup_key with
1139 -- the IsBootInterface parameter True; else False
1142 type NodeKey = (Module, HscSource) -- The nodes of the graph are
1143 type NodeMap a = FiniteMap NodeKey a -- keyed by (mod, src_file_type) pairs
1145 msKey :: ModSummary -> NodeKey
1146 msKey (ModSummary { ms_mod = mod, ms_hsc_src = boot }) = (mod,boot)
1148 emptyNodeMap :: NodeMap a
1149 emptyNodeMap = emptyFM
1151 mkNodeMap :: [ModSummary] -> NodeMap ModSummary
1152 mkNodeMap summaries = listToFM [ (msKey s, s) | s <- summaries]
1154 nodeMapElts :: NodeMap a -> [a]
1155 nodeMapElts = eltsFM
1157 -- -----------------------------------------------------------------
1158 -- The unlinked image
1160 -- The compilation manager keeps a list of compiled, but as-yet unlinked
1161 -- binaries (byte code or object code). Even when it links bytecode
1162 -- it keeps the unlinked version so it can re-link it later without
1165 type UnlinkedImage = [Linkable] -- the unlinked images (should be a set, really)
1167 findModuleLinkable_maybe :: [Linkable] -> Module -> Maybe Linkable
1168 findModuleLinkable_maybe lis mod
1169 = case [LM time nm us | LM time nm us <- lis, nm == mod] of
1172 many -> pprPanic "findModuleLinkable" (ppr mod)
1174 delModuleLinkable :: [Linkable] -> Module -> [Linkable]
1175 delModuleLinkable ls mod = [ l | l@(LM _ nm _) <- ls, nm /= mod ]
1177 -----------------------------------------------------------------------------
1178 -- Downsweep (dependency analysis)
1180 -- Chase downwards from the specified root set, returning summaries
1181 -- for all home modules encountered. Only follow source-import
1184 -- We pass in the previous collection of summaries, which is used as a
1185 -- cache to avoid recalculating a module summary if the source is
1188 -- The returned list of [ModSummary] nodes has one node for each home-package
1189 -- module, plus one for any hs-boot files. The imports of these nodes
1190 -- are all there, including the imports of non-home-package modules.
1193 -> [ModSummary] -- Old summaries
1194 -> [Module] -- Ignore dependencies on these; treat them as
1195 -- if they were package modules
1197 downsweep hsc_env old_summaries excl_mods
1198 = do rootSummaries <- mapM getRootSummary roots
1199 checkDuplicates rootSummaries
1200 loop (concatMap msDeps rootSummaries)
1201 (mkNodeMap rootSummaries)
1203 roots = hsc_targets hsc_env
1205 old_summary_map :: NodeMap ModSummary
1206 old_summary_map = mkNodeMap old_summaries
1208 getRootSummary :: Target -> IO ModSummary
1209 getRootSummary (Target (TargetFile file) maybe_buf)
1210 = do exists <- doesFileExist file
1211 if exists then summariseFile hsc_env file maybe_buf else do
1212 throwDyn (CmdLineError ("can't find file: " ++ file))
1213 getRootSummary (Target (TargetModule modl) maybe_buf)
1214 = do maybe_summary <- summarise hsc_env emptyNodeMap Nothing False
1215 modl maybe_buf excl_mods
1216 case maybe_summary of
1217 Nothing -> packageModErr modl
1220 -- In a root module, the filename is allowed to diverge from the module
1221 -- name, so we have to check that there aren't multiple root files
1222 -- defining the same module (otherwise the duplicates will be silently
1223 -- ignored, leading to confusing behaviour).
1224 checkDuplicates :: [ModSummary] -> IO ()
1225 checkDuplicates summaries = mapM_ check summaries
1230 many -> multiRootsErr modl many
1231 where modl = ms_mod summ
1233 [ expectJust "checkDup" (ml_hs_file (ms_location summ'))
1234 | summ' <- summaries, ms_mod summ' == modl ]
1236 loop :: [(FilePath,Module,IsBootInterface)]
1237 -- Work list: process these modules
1238 -> NodeMap ModSummary
1241 -- The result includes the worklist, except
1242 -- for those mentioned in the visited set
1243 loop [] done = return (nodeMapElts done)
1244 loop ((cur_path, wanted_mod, is_boot) : ss) done
1245 | key `elemFM` done = loop ss done
1246 | otherwise = do { mb_s <- summarise hsc_env old_summary_map
1247 (Just cur_path) is_boot
1248 wanted_mod Nothing excl_mods
1250 Nothing -> loop ss done
1251 Just s -> loop (msDeps s ++ ss)
1252 (addToFM done key s) }
1254 key = (wanted_mod, if is_boot then HsBootFile else HsSrcFile)
1256 msDeps :: ModSummary -> [(FilePath, -- Importing module
1257 Module, -- Imported module
1258 IsBootInterface)] -- {-# SOURCE #-} import or not
1259 -- (msDeps s) returns the dependencies of the ModSummary s.
1260 -- A wrinkle is that for a {-# SOURCE #-} import we return
1261 -- *both* the hs-boot file
1262 -- *and* the source file
1263 -- as "dependencies". That ensures that the list of all relevant
1264 -- modules always contains B.hs if it contains B.hs-boot.
1265 -- Remember, this pass isn't doing the topological sort. It's
1266 -- just gathering the list of all relevant ModSummaries
1267 msDeps s = concat [ [(f, m, True), (f,m,False)] | m <- ms_srcimps s]
1268 ++ [(f,m,False) | m <- ms_imps s]
1270 f = msHsFilePath s -- Keep the importing module for error reporting
1273 -----------------------------------------------------------------------------
1274 -- Summarising modules
1276 -- We have two types of summarisation:
1278 -- * Summarise a file. This is used for the root module(s) passed to
1279 -- cmLoadModules. The file is read, and used to determine the root
1280 -- module name. The module name may differ from the filename.
1282 -- * Summarise a module. We are given a module name, and must provide
1283 -- a summary. The finder is used to locate the file in which the module
1286 summariseFile :: HscEnv -> FilePath
1287 -> Maybe (StringBuffer,ClockTime)
1289 -- Used for Haskell source only, I think
1290 -- We know the file name, and we know it exists,
1291 -- but we don't necessarily know the module name (might differ)
1292 summariseFile hsc_env file maybe_buf
1293 = do let dflags = hsc_dflags hsc_env
1295 (dflags', hspp_fn, buf)
1296 <- preprocessFile dflags file maybe_buf
1298 (srcimps,the_imps,mod) <- getImports dflags' buf hspp_fn
1300 -- Make a ModLocation for this file
1301 location <- mkHomeModLocation dflags mod file
1303 -- Tell the Finder cache where it is, so that subsequent calls
1304 -- to findModule will find it, even if it's not on any search path
1305 addHomeModuleToFinder hsc_env mod location
1307 src_timestamp <- case maybe_buf of
1308 Just (_,t) -> return t
1309 Nothing -> getModificationTime file
1311 obj_timestamp <- modificationTimeIfExists (ml_obj_file location)
1313 return (ModSummary { ms_mod = mod, ms_hsc_src = HsSrcFile,
1314 ms_location = location,
1315 ms_hspp_file = Just hspp_fn,
1316 ms_hspp_buf = Just buf,
1317 ms_srcimps = srcimps, ms_imps = the_imps,
1318 ms_hs_date = src_timestamp,
1319 ms_obj_date = obj_timestamp })
1321 -- Summarise a module, and pick up source and timestamp.
1323 -> NodeMap ModSummary -- Map of old summaries
1324 -> Maybe FilePath -- Importing module (for error messages)
1325 -> IsBootInterface -- True <=> a {-# SOURCE #-} import
1326 -> Module -- Imported module to be summarised
1327 -> Maybe (StringBuffer, ClockTime)
1328 -> [Module] -- Modules to exclude
1329 -> IO (Maybe ModSummary) -- Its new summary
1331 summarise hsc_env old_summary_map cur_mod is_boot wanted_mod maybe_buf excl_mods
1332 | wanted_mod `elem` excl_mods
1335 | Just old_summary <- lookupFM old_summary_map (wanted_mod, hsc_src)
1336 = do -- Find its new timestamp; all the
1337 -- ModSummaries in the old map have valid ml_hs_files
1338 let location = ms_location old_summary
1339 src_fn = expectJust "summarise" (ml_hs_file location)
1341 -- return the cached summary if the source didn't change
1342 src_timestamp <- case maybe_buf of
1343 Just (_,t) -> return t
1344 Nothing -> getModificationTime src_fn
1346 if ms_hs_date old_summary == src_timestamp
1347 then do -- update the object-file timestamp
1348 obj_timestamp <- getObjTimestamp location is_boot
1349 return (Just old_summary{ ms_obj_date = obj_timestamp })
1351 -- source changed: re-summarise
1352 new_summary location src_fn maybe_buf src_timestamp
1355 = do found <- findModule hsc_env wanted_mod True {-explicit-}
1358 | not (isHomePackage pkg) -> return Nothing
1359 -- Drop external-pkg
1360 | isJust (ml_hs_file location) -> just_found location
1362 err -> noModError dflags cur_mod wanted_mod err
1365 dflags = hsc_dflags hsc_env
1367 hsc_src = if is_boot then HsBootFile else HsSrcFile
1369 just_found location = do
1370 -- Adjust location to point to the hs-boot source file,
1371 -- hi file, object file, when is_boot says so
1372 let location' | is_boot = addBootSuffixLocn location
1373 | otherwise = location
1374 src_fn = expectJust "summarise2" (ml_hs_file location')
1376 -- Check that it exists
1377 -- It might have been deleted since the Finder last found it
1378 maybe_t <- modificationTimeIfExists src_fn
1380 Nothing -> noHsFileErr cur_mod src_fn
1381 Just t -> new_summary location' src_fn Nothing t
1384 new_summary location src_fn maybe_bug src_timestamp
1386 -- Preprocess the source file and get its imports
1387 -- The dflags' contains the OPTIONS pragmas
1388 (dflags', hspp_fn, buf) <- preprocessFile dflags src_fn maybe_buf
1389 (srcimps, the_imps, mod_name) <- getImports dflags' buf hspp_fn
1391 when (mod_name /= wanted_mod) $
1392 throwDyn (ProgramError
1393 (showSDoc (text src_fn
1394 <> text ": file name does not match module name"
1395 <+> quotes (ppr mod_name))))
1397 -- Find the object timestamp, and return the summary
1398 obj_timestamp <- getObjTimestamp location is_boot
1400 return (Just ( ModSummary { ms_mod = wanted_mod,
1401 ms_hsc_src = hsc_src,
1402 ms_location = location,
1403 ms_hspp_file = Just hspp_fn,
1404 ms_hspp_buf = Just buf,
1405 ms_srcimps = srcimps,
1407 ms_hs_date = src_timestamp,
1408 ms_obj_date = obj_timestamp }))
1411 getObjTimestamp location is_boot
1412 = if is_boot then return Nothing
1413 else modificationTimeIfExists (ml_obj_file location)
1416 preprocessFile :: DynFlags -> FilePath -> Maybe (StringBuffer,ClockTime)
1417 -> IO (DynFlags, FilePath, StringBuffer)
1418 preprocessFile dflags src_fn Nothing
1420 (dflags', hspp_fn) <- preprocess dflags src_fn
1421 buf <- hGetStringBuffer hspp_fn
1422 return (dflags', hspp_fn, buf)
1424 preprocessFile dflags src_fn (Just (buf, time))
1426 -- case we bypass the preprocessing stage?
1428 local_opts = getOptionsFromStringBuffer buf
1430 (dflags', errs) <- parseDynamicFlags dflags (map snd local_opts)
1434 | Unlit _ <- startPhase src_fn = True
1435 -- note: local_opts is only required if there's no Unlit phase
1436 | dopt Opt_Cpp dflags' = True
1437 | dopt Opt_Pp dflags' = True
1440 when needs_preprocessing $
1441 ghcError (ProgramError "buffer needs preprocesing; interactive check disabled")
1443 return (dflags', src_fn, buf)
1446 -----------------------------------------------------------------------------
1448 -----------------------------------------------------------------------------
1450 noModError :: DynFlags -> Maybe FilePath -> Module -> FindResult -> IO ab
1451 -- ToDo: we don't have a proper line number for this error
1452 noModError dflags cur_mod wanted_mod err
1453 = throwDyn $ ProgramError $ showSDoc $
1454 vcat [cantFindError dflags wanted_mod err,
1455 nest 2 (parens (pp_where cur_mod))]
1457 noHsFileErr cur_mod path
1458 = throwDyn $ CmdLineError $ showSDoc $
1459 vcat [text "Can't find" <+> text path,
1460 nest 2 (parens (pp_where cur_mod))]
1462 pp_where Nothing = text "one of the roots of the dependency analysis"
1463 pp_where (Just p) = text "imported from" <+> text p
1466 = throwDyn (CmdLineError (showSDoc (text "module" <+>
1467 quotes (ppr mod) <+>
1468 text "is a package module")))
1470 multiRootsErr mod files
1471 = throwDyn (ProgramError (showSDoc (
1472 text "module" <+> quotes (ppr mod) <+>
1473 text "is defined in multiple files:" <+>
1474 sep (map text files))))
1476 cyclicModuleErr :: [ModSummary] -> SDoc
1478 = hang (ptext SLIT("Module imports form a cycle for modules:"))
1479 2 (vcat (map show_one ms))
1481 show_one ms = sep [ show_mod (ms_hsc_src ms) (ms_mod ms),
1482 nest 2 $ ptext SLIT("imports:") <+>
1483 (pp_imps HsBootFile (ms_srcimps ms)
1484 $$ pp_imps HsSrcFile (ms_imps ms))]
1485 show_mod hsc_src mod = ppr mod <> text (hscSourceString hsc_src)
1486 pp_imps src mods = fsep (map (show_mod src) mods)
1489 -- | Inform GHC that the working directory has changed. GHC will flush
1490 -- its cache of module locations, since it may no longer be valid.
1491 -- Note: if you change the working directory, you should also unload
1492 -- the current program (set targets to empty, followed by load).
1493 workingDirectoryChanged :: Session -> IO ()
1494 workingDirectoryChanged s = withSession s $ \hsc_env ->
1495 flushFinderCache (hsc_FC hsc_env)
1497 -- -----------------------------------------------------------------------------
1498 -- inspecting the session
1500 -- | Get the module dependency graph.
1501 getModuleGraph :: Session -> IO ModuleGraph -- ToDo: DiGraph ModSummary
1502 getModuleGraph s = withSession s (return . hsc_mod_graph)
1504 isLoaded :: Session -> Module -> IO Bool
1505 isLoaded s m = withSession s $ \hsc_env ->
1506 return $! isJust (lookupModuleEnv (hsc_HPT hsc_env) m)
1508 getBindings :: Session -> IO [TyThing]
1509 getBindings s = withSession s (return . nameEnvElts . ic_type_env . hsc_IC)
1511 getPrintUnqual :: Session -> IO PrintUnqualified
1512 getPrintUnqual s = withSession s (return . icPrintUnqual . hsc_IC)
1514 -- | Container for information about a 'Module'.
1515 data ModuleInfo = ModuleInfo {
1516 minf_details :: ModDetails,
1517 minf_rdr_env :: Maybe GlobalRdrEnv
1519 -- ToDo: this should really contain the ModIface too
1520 -- We don't want HomeModInfo here, because a ModuleInfo applies
1521 -- to package modules too.
1523 -- | Request information about a loaded 'Module'
1524 getModuleInfo :: Session -> Module -> IO (Maybe ModuleInfo)
1525 getModuleInfo s mdl = withSession s $ \hsc_env -> do
1526 case lookupModuleEnv (hsc_HPT hsc_env) mdl of
1527 Nothing -> return Nothing
1529 return (Just (ModuleInfo {
1530 minf_details = hm_details hmi,
1531 minf_rdr_env = mi_globals $! hm_iface hmi
1534 -- ToDo: we should be able to call getModuleInfo on a package module,
1535 -- even one that isn't loaded yet.
1537 -- | The list of top-level entities defined in a module
1538 modInfoTyThings :: ModuleInfo -> [TyThing]
1539 modInfoTyThings minf = typeEnvElts (md_types (minf_details minf))
1541 modInfoTopLevelScope :: ModuleInfo -> Maybe [Name]
1542 modInfoTopLevelScope minf
1543 = fmap (map gre_name . globalRdrEnvElts) (minf_rdr_env minf)
1545 modInfoExports :: ModuleInfo -> [Name]
1546 modInfoExports minf = nameSetToList $! (md_exports $! minf_details minf)
1548 modInfoPrintUnqualified :: ModuleInfo -> Maybe PrintUnqualified
1549 modInfoPrintUnqualified minf = fmap unQualInScope (minf_rdr_env minf)
1551 isDictonaryId :: Id -> Bool
1553 = case tcSplitSigmaTy (idType id) of { (tvs, theta, tau) -> isDictTy tau }
1555 -- | Looks up a global name: that is, any top-level name in any
1556 -- visible module. Unlike 'lookupName', lookupGlobalName does not use
1557 -- the interactive context, and therefore does not require a preceding
1559 lookupGlobalName :: Session -> Name -> IO (Maybe TyThing)
1560 lookupGlobalName s name = withSession s $ \hsc_env -> do
1561 eps <- readIORef (hsc_EPS hsc_env)
1562 return $! lookupType (hsc_HPT hsc_env) (eps_PTE eps) name
1568 | BinaryCode FilePath
1570 -- ToDo: typechecks abstract syntax or renamed abstract syntax. Issues:
1571 -- - typechecked syntax includes extra dictionary translation and
1572 -- AbsBinds which need to be translated back into something closer to
1573 -- the original source.
1576 -- - Data and Typeable instances for HsSyn.
1579 -- - things that aren't in the output of the renamer:
1580 -- - the export list
1584 -- - things that aren't in the output of the typechecker right now:
1585 -- - the export list
1587 -- - type signatures
1588 -- - type/data/newtype declarations
1589 -- - class declarations
1591 -- - extra things in the typechecker's output:
1592 -- - default methods are turned into top-level decls.
1593 -- - dictionary bindings
1595 -- ToDo: check for small transformations that happen to the syntax in
1596 -- the typechecker (eg. -e ==> negate e, perhaps for fromIntegral)
1598 -- ToDo: maybe use TH syntax instead of IfaceSyn? There's already a way
1599 -- to get from TyCons, Ids etc. to TH syntax (reify).
1601 -- :browse will use either lm_toplev or inspect lm_interface, depending
1602 -- on whether the module is interpreted or not.
1604 -- This is for reconstructing refactored source code
1605 -- Calls the lexer repeatedly.
1606 -- ToDo: add comment tokens to token stream
1607 getTokenStream :: Session -> Module -> IO [Located Token]
1610 -- -----------------------------------------------------------------------------
1611 -- Interactive evaluation
1615 -- | Set the interactive evaluation context.
1617 -- Setting the context doesn't throw away any bindings; the bindings
1618 -- we've built up in the InteractiveContext simply move to the new
1619 -- module. They always shadow anything in scope in the current context.
1620 setContext :: Session
1621 -> [Module] -- entire top level scope of these modules
1622 -> [Module] -- exports only of these modules
1624 setContext (Session ref) toplevs exports = do
1625 hsc_env <- readIORef ref
1626 let old_ic = hsc_IC hsc_env
1627 hpt = hsc_HPT hsc_env
1629 mapM_ (checkModuleExists hsc_env hpt) exports
1630 export_env <- mkExportEnv hsc_env exports
1631 toplev_envs <- mapM (mkTopLevEnv hpt) toplevs
1632 let all_env = foldr plusGlobalRdrEnv export_env toplev_envs
1633 writeIORef ref hsc_env{ hsc_IC = old_ic { ic_toplev_scope = toplevs,
1634 ic_exports = exports,
1635 ic_rn_gbl_env = all_env } }
1637 checkModuleExists :: HscEnv -> HomePackageTable -> Module -> IO ()
1638 checkModuleExists hsc_env hpt mod =
1639 case lookupModuleEnv hpt mod of
1640 Just mod_info -> return ()
1641 _not_a_home_module -> do
1642 res <- findPackageModule hsc_env mod True
1644 Found _ _ -> return ()
1645 err -> let msg = cantFindError (hsc_dflags hsc_env) mod err in
1646 throwDyn (CmdLineError (showSDoc msg))
1648 mkTopLevEnv :: HomePackageTable -> Module -> IO GlobalRdrEnv
1649 mkTopLevEnv hpt modl
1650 = case lookupModuleEnv hpt modl of
1652 throwDyn (ProgramError ("mkTopLevEnv: not a home module "
1653 ++ showSDoc (pprModule modl)))
1655 case mi_globals (hm_iface details) of
1657 throwDyn (ProgramError ("mkTopLevEnv: not interpreted "
1658 ++ showSDoc (pprModule modl)))
1659 Just env -> return env
1661 -- | Get the interactive evaluation context, consisting of a pair of the
1662 -- set of modules from which we take the full top-level scope, and the set
1663 -- of modules from which we take just the exports respectively.
1664 getContext :: Session -> IO ([Module],[Module])
1665 getContext s = withSession s (\HscEnv{ hsc_IC=ic } ->
1666 return (ic_toplev_scope ic, ic_exports ic))
1668 -- | Returns 'True' if the specified module is interpreted, and hence has
1669 -- its full top-level scope available.
1670 moduleIsInterpreted :: Session -> Module -> IO Bool
1671 moduleIsInterpreted s modl = withSession s $ \h ->
1672 case lookupModuleEnv (hsc_HPT h) modl of
1673 Just details -> return (isJust (mi_globals (hm_iface details)))
1674 _not_a_home_module -> return False
1676 -- | Looks up an identifier in the current interactive context (for :info)
1677 {-# DEPRECATED getInfo "we should be using parseName/lookupName instead" #-}
1678 getInfo :: Session -> String -> IO [GetInfoResult]
1679 getInfo s id = withSession s $ \hsc_env -> hscGetInfo hsc_env id
1681 -- | Returns all names in scope in the current interactive context
1682 getNamesInScope :: Session -> IO [Name]
1683 getNamesInScope s = withSession s $ \hsc_env -> do
1684 return (map gre_name (globalRdrEnvElts (ic_rn_gbl_env (hsc_IC hsc_env))))
1686 -- | Parses a string as an identifier, and returns the list of 'Name's that
1687 -- the identifier can refer to in the current interactive context.
1688 parseName :: Session -> String -> IO [Name]
1689 parseName s str = withSession s $ \hsc_env -> do
1690 maybe_rdr_name <- hscParseIdentifier (hsc_dflags hsc_env) str
1691 case maybe_rdr_name of
1692 Nothing -> return []
1693 Just (L _ rdr_name) -> do
1694 mb_names <- tcRnLookupRdrName hsc_env rdr_name
1696 Nothing -> return []
1697 Just ns -> return ns
1698 -- ToDo: should return error messages
1700 -- | Returns the 'TyThing' for a 'Name'. The 'Name' may refer to any
1701 -- entity known to GHC, including 'Name's defined using 'runStmt'.
1702 lookupName :: Session -> Name -> IO (Maybe TyThing)
1703 lookupName s name = withSession s $ \hsc_env -> do
1704 case lookupTypeEnv (ic_type_env (hsc_IC hsc_env)) name of
1705 Just tt -> return (Just tt)
1707 eps <- readIORef (hsc_EPS hsc_env)
1708 return $! lookupType (hsc_HPT hsc_env) (eps_PTE eps) name
1710 -- -----------------------------------------------------------------------------
1711 -- Getting the type of an expression
1713 -- | Get the type of an expression
1714 exprType :: Session -> String -> IO (Maybe Type)
1715 exprType s expr = withSession s $ \hsc_env -> do
1716 maybe_stuff <- hscTcExpr hsc_env expr
1718 Nothing -> return Nothing
1719 Just ty -> return (Just tidy_ty)
1721 tidy_ty = tidyType emptyTidyEnv ty
1722 dflags = hsc_dflags hsc_env
1724 -- -----------------------------------------------------------------------------
1725 -- Getting the kind of a type
1727 -- | Get the kind of a type
1728 typeKind :: Session -> String -> IO (Maybe Kind)
1729 typeKind s str = withSession s $ \hsc_env -> do
1730 maybe_stuff <- hscKcType hsc_env str
1732 Nothing -> return Nothing
1733 Just kind -> return (Just kind)
1735 -----------------------------------------------------------------------------
1736 -- cmCompileExpr: compile an expression and deliver an HValue
1738 compileExpr :: Session -> String -> IO (Maybe HValue)
1739 compileExpr s expr = withSession s $ \hsc_env -> do
1740 maybe_stuff <- hscStmt hsc_env ("let __cmCompileExpr = "++expr)
1742 Nothing -> return Nothing
1743 Just (new_ic, names, hval) -> do
1745 hvals <- (unsafeCoerce# hval) :: IO [HValue]
1747 case (names,hvals) of
1748 ([n],[hv]) -> return (Just hv)
1749 _ -> panic "compileExpr"
1751 -- -----------------------------------------------------------------------------
1752 -- running a statement interactively
1755 = RunOk [Name] -- ^ names bound by this evaluation
1756 | RunFailed -- ^ statement failed compilation
1757 | RunException Exception -- ^ statement raised an exception
1759 -- | Run a statement in the current interactive context. Statemenet
1760 -- may bind multple values.
1761 runStmt :: Session -> String -> IO RunResult
1762 runStmt (Session ref) expr
1764 hsc_env <- readIORef ref
1766 -- Turn off -fwarn-unused-bindings when running a statement, to hide
1767 -- warnings about the implicit bindings we introduce.
1768 let dflags' = dopt_unset (hsc_dflags hsc_env) Opt_WarnUnusedBinds
1769 hsc_env' = hsc_env{ hsc_dflags = dflags' }
1771 maybe_stuff <- hscStmt hsc_env' expr
1774 Nothing -> return RunFailed
1775 Just (new_hsc_env, names, hval) -> do
1777 let thing_to_run = unsafeCoerce# hval :: IO [HValue]
1778 either_hvals <- sandboxIO thing_to_run
1780 case either_hvals of
1782 -- on error, keep the *old* interactive context,
1783 -- so that 'it' is not bound to something
1784 -- that doesn't exist.
1785 return (RunException e)
1788 -- Get the newly bound things, and bind them.
1789 -- Don't need to delete any shadowed bindings;
1790 -- the new ones override the old ones.
1791 extendLinkEnv (zip names hvals)
1793 writeIORef ref new_hsc_env
1794 return (RunOk names)
1797 -- We run the statement in a "sandbox" to protect the rest of the
1798 -- system from anything the expression might do. For now, this
1799 -- consists of just wrapping it in an exception handler, but see below
1800 -- for another version.
1802 sandboxIO :: IO a -> IO (Either Exception a)
1803 sandboxIO thing = Exception.try thing
1806 -- This version of sandboxIO runs the expression in a completely new
1807 -- RTS main thread. It is disabled for now because ^C exceptions
1808 -- won't be delivered to the new thread, instead they'll be delivered
1809 -- to the (blocked) GHCi main thread.
1811 -- SLPJ: when re-enabling this, reflect a wrong-stat error as an exception
1813 sandboxIO :: IO a -> IO (Either Int (Either Exception a))
1814 sandboxIO thing = do
1815 st_thing <- newStablePtr (Exception.try thing)
1816 alloca $ \ p_st_result -> do
1817 stat <- rts_evalStableIO st_thing p_st_result
1818 freeStablePtr st_thing
1820 then do st_result <- peek p_st_result
1821 result <- deRefStablePtr st_result
1822 freeStablePtr st_result
1823 return (Right result)
1825 return (Left (fromIntegral stat))
1827 foreign import "rts_evalStableIO" {- safe -}
1828 rts_evalStableIO :: StablePtr (IO a) -> Ptr (StablePtr a) -> IO CInt
1829 -- more informative than the C type!
1832 -- ---------------------------------------------------------------------------
1833 -- cmBrowseModule: get all the TyThings defined in a module
1835 {-# DEPRECATED browseModule "we should be using getModuleInfo instead" #-}
1836 browseModule :: Session -> Module -> Bool -> IO [IfaceDecl]
1837 browseModule s modl exports_only = withSession s $ \hsc_env -> do
1838 mb_decls <- getModuleContents hsc_env modl exports_only
1840 Nothing -> return [] -- An error of some kind
1841 Just ds -> return ds
1844 -----------------------------------------------------------------------------
1845 -- show a module and it's source/object filenames
1847 showModule :: Session -> ModSummary -> IO String
1848 showModule s mod_summary = withSession s $ \hsc_env -> do
1849 case lookupModuleEnv (hsc_HPT hsc_env) (ms_mod mod_summary) of
1850 Nothing -> panic "missing linkable"
1851 Just mod_info -> return (showModMsg obj_linkable mod_summary)
1853 obj_linkable = isObjectLinkable (fromJust (hm_linkable mod_info))