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(..),
40 -- * Inspecting the module structure of the program
41 ModuleGraph, ModSummary(..),
46 -- * Inspecting modules
53 -- * Interactive evaluation
54 getBindings, getPrintUnqual,
56 setContext, getContext,
59 getInfo, GetInfoResult,
70 -- * Abstract syntax elements
73 Module, mkModule, pprModule,
80 isImplicitId, isDeadBinder,
81 isSpecPragmaId, isExportedId, isLocalId, isGlobalId,
83 isPrimOpId, isFCallId,
84 isDataConWorkId, idDataCon,
85 isBottomingId, isDictonaryId,
87 -- ** Type constructors
89 isClassTyCon, isSynTyCon, isNewTyCon,
91 -- ** Data constructors
96 classSCTheta, classTvsFds,
106 GhcException(..), showGhcException,
116 * return error messages rather than printing them.
117 * inline bits of HscMain here to simplify layering: hscGetInfo,
119 * implement second argument to load.
120 * we need to expose DynFlags, so should parseDynamicFlags really be
121 part of this interface?
122 * what StaticFlags should we expose, if any?
125 #include "HsVersions.h"
128 import qualified Linker
129 import Linker ( HValue, extendLinkEnv )
130 import NameEnv ( lookupNameEnv )
131 import TcRnDriver ( mkExportEnv, getModuleContents, tcRnLookupRdrName )
132 import RdrName ( plusGlobalRdrEnv )
133 import HscMain ( hscGetInfo, GetInfoResult, hscParseIdentifier,
134 hscStmt, hscTcExpr, hscKcType )
135 import Type ( tidyType )
136 import VarEnv ( emptyTidyEnv )
137 import GHC.Exts ( unsafeCoerce# )
138 import IfaceSyn ( IfaceDecl )
141 import Packages ( initPackages )
142 import NameSet ( NameSet, nameSetToList )
143 import RdrName ( GlobalRdrEnv )
144 import HsSyn ( HsModule, LHsBinds )
145 import Type ( Kind, Type, dropForAlls )
146 import Id ( Id, idType, isImplicitId, isDeadBinder,
147 isSpecPragmaId, isExportedId, isLocalId, isGlobalId,
149 isPrimOpId, isFCallId,
150 isDataConWorkId, idDataCon,
152 import TyCon ( TyCon, isClassTyCon, isSynTyCon, isNewTyCon )
153 import Class ( Class, classSCTheta, classTvsFds )
154 import DataCon ( DataCon )
155 import Name ( Name, getName, nameModule_maybe )
156 import RdrName ( RdrName, gre_name, globalRdrEnvElts )
157 import NameEnv ( nameEnvElts )
158 import SrcLoc ( Located(..), mkSrcLoc, srcLocSpan )
159 import DriverPipeline
160 import DriverPhases ( Phase(..), isHaskellSrcFilename, startPhase )
161 import GetImports ( getImports )
162 import Packages ( isHomePackage )
164 import HscMain ( newHscEnv, hscFileCheck, HscResult(..) )
168 import SysTools ( initSysTools, cleanTempFiles )
173 import ErrUtils ( showPass, Messages, putMsg, debugTraceMsg )
174 import qualified ErrUtils
176 import StringBuffer ( StringBuffer, hGetStringBuffer )
178 import SysTools ( cleanTempFilesExcept )
179 import BasicTypes ( SuccessFlag(..), succeeded, failed )
180 import Maybes ( orElse, expectJust, mapCatMaybes )
181 import TcType ( tcSplitSigmaTy, isDictTy )
182 import Bag ( unitBag, emptyBag )
183 import FastString ( mkFastString )
185 import Directory ( getModificationTime, doesFileExist )
186 import Maybe ( isJust, isNothing, fromJust, fromMaybe, catMaybes )
187 import Maybes ( expectJust )
188 import List ( partition, nub )
189 import qualified List
190 import Monad ( unless, when, foldM )
191 import System ( exitWith, ExitCode(..) )
192 import Time ( ClockTime )
193 import EXCEPTION as Exception hiding (handle)
196 import Prelude hiding (init)
198 -- -----------------------------------------------------------------------------
199 -- Exception handlers
201 -- | Install some default exception handlers and run the inner computation.
202 -- Unless you want to handle exceptions yourself, you should wrap this around
203 -- the top level of your program. The default handlers output the error
204 -- message(s) to stderr and exit cleanly.
205 defaultErrorHandler :: IO a -> IO a
206 defaultErrorHandler inner =
207 -- top-level exception handler: any unrecognised exception is a compiler bug.
208 handle (\exception -> do
211 -- an IO exception probably isn't our fault, so don't panic
212 IOException _ -> putMsg (show exception)
213 AsyncException StackOverflow ->
214 putMsg "stack overflow: use +RTS -K<size> to increase it"
215 _other -> putMsg (show (Panic (show exception)))
216 exitWith (ExitFailure 1)
219 -- all error messages are propagated as exceptions
220 handleDyn (\dyn -> do
223 PhaseFailed _ code -> exitWith code
224 Interrupted -> exitWith (ExitFailure 1)
225 _ -> do putMsg (show (dyn :: GhcException))
226 exitWith (ExitFailure 1)
230 -- | Install a default cleanup handler to remove temporary files
231 -- deposited by a GHC run. This is seperate from
232 -- 'defaultErrorHandler', because you might want to override the error
233 -- handling, but still get the ordinary cleanup behaviour.
234 defaultCleanupHandler :: DynFlags -> IO a -> IO a
235 defaultCleanupHandler dflags inner =
236 -- make sure we clean up after ourselves
237 later (unless (dopt Opt_KeepTmpFiles dflags) $
238 cleanTempFiles dflags)
239 -- exceptions will be blocked while we clean the temporary files,
240 -- so there shouldn't be any difficulty if we receive further
245 -- | Initialises GHC. This must be done /once/ only. Takes the
246 -- command-line arguments. All command-line arguments which aren't
247 -- understood by GHC will be returned.
249 init :: [String] -> IO [String]
252 installSignalHandlers
254 -- Grab the -B option if there is one
255 let (minusB_args, argv1) = partition (prefixMatch "-B") args
256 dflags0 <- initSysTools minusB_args defaultDynFlags
257 writeIORef v_initDynFlags dflags0
259 -- Parse the static flags
260 argv2 <- parseStaticFlags argv1
263 GLOBAL_VAR(v_initDynFlags, error "initDynFlags", DynFlags)
264 -- stores the DynFlags between the call to init and subsequent
265 -- calls to newSession.
267 -- | Starts a new session. A session consists of a set of loaded
268 -- modules, a set of options (DynFlags), and an interactive context.
269 -- ToDo: GhcMode should say "keep typechecked code" and\/or "keep renamed
271 newSession :: GhcMode -> IO Session
273 dflags0 <- readIORef v_initDynFlags
274 dflags <- initDynFlags dflags0
275 env <- newHscEnv dflags{ ghcMode=mode }
279 -- tmp: this breaks the abstraction, but required because DriverMkDepend
280 -- needs to call the Finder. ToDo: untangle this.
281 sessionHscEnv :: Session -> IO HscEnv
282 sessionHscEnv (Session ref) = readIORef ref
284 withSession :: Session -> (HscEnv -> IO a) -> IO a
285 withSession (Session ref) f = do h <- readIORef ref; f h
287 modifySession :: Session -> (HscEnv -> HscEnv) -> IO ()
288 modifySession (Session ref) f = do h <- readIORef ref; writeIORef ref $! f h
290 -- -----------------------------------------------------------------------------
293 -- | Grabs the DynFlags from the Session
294 getSessionDynFlags :: Session -> IO DynFlags
295 getSessionDynFlags s = withSession s (return . hsc_dflags)
297 -- | Updates the DynFlags in a Session
298 setSessionDynFlags :: Session -> DynFlags -> IO ()
299 setSessionDynFlags s dflags = modifySession s (\h -> h{ hsc_dflags = dflags })
301 -- | Messages during compilation (eg. warnings and progress messages)
302 -- are reported using this callback. By default, these messages are
303 -- printed to stderr.
304 setMsgHandler :: (String -> IO ()) -> IO ()
305 setMsgHandler = ErrUtils.setMsgHandler
307 -- -----------------------------------------------------------------------------
310 -- ToDo: think about relative vs. absolute file paths. And what
311 -- happens when the current directory changes.
313 -- | Sets the targets for this session. Each target may be a module name
314 -- or a filename. The targets correspond to the set of root modules for
315 -- the program\/library. Unloading the current program is achieved by
316 -- setting the current set of targets to be empty, followed by load.
317 setTargets :: Session -> [Target] -> IO ()
318 setTargets s targets = modifySession s (\h -> h{ hsc_targets = targets })
320 -- | returns the current set of targets
321 getTargets :: Session -> IO [Target]
322 getTargets s = withSession s (return . hsc_targets)
324 -- | Add another target
325 addTarget :: Session -> Target -> IO ()
327 = modifySession s (\h -> h{ hsc_targets = target : hsc_targets h })
330 removeTarget :: Session -> TargetId -> IO ()
331 removeTarget s target_id
332 = modifySession s (\h -> h{ hsc_targets = filter (hsc_targets h) })
334 filter targets = [ t | t@(Target id _) <- targets, id /= target_id ]
336 -- Attempts to guess what Target a string refers to. This function implements
337 -- the --make/GHCi command-line syntax for filenames:
339 -- - if the string looks like a Haskell source filename, then interpret
341 -- - if adding a .hs or .lhs suffix yields the name of an existing file,
343 -- - otherwise interpret the string as a module name
345 guessTarget :: String -> IO Target
347 | isHaskellSrcFilename file
348 = return (Target (TargetFile file) Nothing)
350 = do exists <- doesFileExist hs_file
351 if exists then return (Target (TargetFile hs_file) Nothing) else do
352 exists <- doesFileExist lhs_file
353 if exists then return (Target (TargetFile lhs_file) Nothing) else do
354 return (Target (TargetModule (mkModule file)) Nothing)
356 hs_file = file ++ ".hs"
357 lhs_file = file ++ ".lhs"
359 -- -----------------------------------------------------------------------------
360 -- Loading the program
362 -- Perform a dependency analysis starting from the current targets
363 -- and update the session with the new module graph.
364 depanal :: Session -> [Module] -> IO ()
365 depanal (Session ref) excluded_mods = do
366 hsc_env <- readIORef ref
368 dflags = hsc_dflags hsc_env
369 gmode = ghcMode (hsc_dflags hsc_env)
370 targets = hsc_targets hsc_env
371 old_graph = hsc_mod_graph hsc_env
373 showPass dflags "Chasing dependencies"
374 when (gmode == BatchCompile) $
375 debugTraceMsg dflags 1 (showSDoc (hcat [
376 text "Chasing modules from: ",
377 hcat (punctuate comma (map pprTarget targets))]))
379 graph <- downsweep hsc_env old_graph excluded_mods
380 writeIORef ref hsc_env{ hsc_mod_graph=graph }
383 -- | The result of load.
385 = LoadOk Errors -- ^ all specified targets were loaded successfully.
386 | LoadFailed Errors -- ^ not all modules were loaded.
388 type Errors = [String]
390 data ErrMsg = ErrMsg {
391 errMsgSeverity :: Severity, -- warning, error, etc.
392 errMsgSpans :: [SrcSpan],
393 errMsgShortDoc :: Doc,
394 errMsgExtraInfo :: Doc
401 | LoadDependenciesOf Module
403 -- | Try to load the program. If a Module is supplied, then just
404 -- attempt to load up to this target. If no Module is supplied,
405 -- then try to load all targets.
406 load :: Session -> LoadHowMuch -> IO SuccessFlag
407 load session how_much =
408 loadMsgs session how_much ErrUtils.printErrorsAndWarnings
410 -- | Version of 'load' that takes a callback function to be invoked
411 -- on compiler errors and warnings as they occur during compilation.
412 loadMsgs :: Session -> LoadHowMuch -> (Messages-> IO ()) -> IO SuccessFlag
413 loadMsgs s@(Session ref) how_much msg_act
415 -- Dependency analysis first. Note that this fixes the module graph:
416 -- even if we don't get a fully successful upsweep, the full module
417 -- graph is still retained in the Session. We can tell which modules
418 -- were successfully loaded by inspecting the Session's HPT.
421 hsc_env <- readIORef ref
423 let hpt1 = hsc_HPT hsc_env
424 let dflags = hsc_dflags hsc_env
425 let mod_graph = hsc_mod_graph hsc_env
427 let ghci_mode = ghcMode (hsc_dflags hsc_env) -- this never changes
428 let verb = verbosity dflags
430 -- The "bad" boot modules are the ones for which we have
431 -- B.hs-boot in the module graph, but no B.hs
432 -- The downsweep should have ensured this does not happen
434 let all_home_mods = [ms_mod s | s <- mod_graph, not (isBootSummary s)]
435 bad_boot_mods = [s | s <- mod_graph, isBootSummary s,
436 not (ms_mod s `elem` all_home_mods)]
437 ASSERT( null bad_boot_mods ) return ()
439 -- mg2_with_srcimps drops the hi-boot nodes, returning a
440 -- graph with cycles. Among other things, it is used for
441 -- backing out partially complete cycles following a failed
442 -- upsweep, and for removing from hpt all the modules
443 -- not in strict downwards closure, during calls to compile.
444 let mg2_with_srcimps :: [SCC ModSummary]
445 mg2_with_srcimps = topSortModuleGraph True mod_graph Nothing
447 -- check the stability property for each module.
448 stable_mods@(stable_obj,stable_bco)
449 | BatchCompile <- ghci_mode = ([],[])
450 | otherwise = checkStability hpt1 mg2_with_srcimps all_home_mods
452 -- prune bits of the HPT which are definitely redundant now,
454 pruned_hpt = pruneHomePackageTable hpt1
455 (flattenSCCs mg2_with_srcimps)
460 debugTraceMsg dflags 2 (showSDoc (text "Stable obj:" <+> ppr stable_obj $$
461 text "Stable BCO:" <+> ppr stable_bco))
463 -- Unload any modules which are going to be re-linked this time around.
464 let stable_linkables = [ linkable
465 | m <- stable_obj++stable_bco,
466 Just hmi <- [lookupModuleEnv pruned_hpt m],
467 Just linkable <- [hm_linkable hmi] ]
468 unload hsc_env stable_linkables
470 -- We could at this point detect cycles which aren't broken by
471 -- a source-import, and complain immediately, but it seems better
472 -- to let upsweep_mods do this, so at least some useful work gets
473 -- done before the upsweep is abandoned.
474 --hPutStrLn stderr "after tsort:\n"
475 --hPutStrLn stderr (showSDoc (vcat (map ppr mg2)))
477 -- Now do the upsweep, calling compile for each module in
478 -- turn. Final result is version 3 of everything.
480 -- Topologically sort the module graph, this time including hi-boot
481 -- nodes, and possibly just including the portion of the graph
482 -- reachable from the module specified in the 2nd argument to load.
483 -- This graph should be cycle-free.
484 -- If we're restricting the upsweep to a portion of the graph, we
485 -- also want to retain everything that is still stable.
486 let full_mg :: [SCC ModSummary]
487 full_mg = topSortModuleGraph False mod_graph Nothing
489 maybe_top_mod = case how_much of
491 LoadDependenciesOf m -> Just m
494 partial_mg0 :: [SCC ModSummary]
495 partial_mg0 = topSortModuleGraph False mod_graph maybe_top_mod
497 -- LoadDependenciesOf m: we want the upsweep to stop just
498 -- short of the specified module (unless the specified module
501 | LoadDependenciesOf mod <- how_much
502 = ASSERT( case last partial_mg0 of
503 AcyclicSCC ms -> ms_mod ms == mod; _ -> False )
504 List.init partial_mg0
510 | AcyclicSCC ms <- full_mg,
511 ms_mod ms `elem` stable_obj++stable_bco,
512 ms_mod ms `notElem` [ ms_mod ms' |
513 AcyclicSCC ms' <- partial_mg ] ]
515 mg = stable_mg ++ partial_mg
517 -- clean up between compilations
518 let cleanup = cleanTempFilesExcept dflags
519 (ppFilesFromSummaries (flattenSCCs mg2_with_srcimps))
521 (upsweep_ok, hsc_env1, modsUpswept)
522 <- upsweep (hsc_env { hsc_HPT = emptyHomePackageTable })
523 pruned_hpt stable_mods cleanup msg_act mg
525 -- Make modsDone be the summaries for each home module now
526 -- available; this should equal the domain of hpt3.
527 -- Get in in a roughly top .. bottom order (hence reverse).
529 let modsDone = reverse modsUpswept
531 -- Try and do linking in some form, depending on whether the
532 -- upsweep was completely or only partially successful.
534 if succeeded upsweep_ok
537 -- Easy; just relink it all.
538 do debugTraceMsg dflags 2 "Upsweep completely successful."
540 -- Clean up after ourselves
541 cleanTempFilesExcept dflags (ppFilesFromSummaries modsDone)
543 -- Issue a warning for the confusing case where the user
544 -- said '-o foo' but we're not going to do any linking.
545 -- We attempt linking if either (a) one of the modules is
546 -- called Main, or (b) the user said -no-hs-main, indicating
547 -- that main() is going to come from somewhere else.
549 let ofile = outputFile dflags
550 let no_hs_main = dopt Opt_NoHsMain dflags
551 let mb_main_mod = mainModIs dflags
553 main_mod = mb_main_mod `orElse` "Main"
555 = any ((==main_mod).moduleUserString.ms_mod)
557 do_linking = a_root_is_Main || no_hs_main
559 when (ghci_mode == BatchCompile && isJust ofile && not do_linking) $
560 debugTraceMsg dflags 1 ("Warning: output was redirected with -o, " ++
561 "but no output will be generated\n" ++
562 "because there is no " ++ main_mod ++ " module.")
564 -- link everything together
565 linkresult <- link ghci_mode dflags do_linking (hsc_HPT hsc_env1)
567 loadFinish Succeeded linkresult ref hsc_env1
570 -- Tricky. We need to back out the effects of compiling any
571 -- half-done cycles, both so as to clean up the top level envs
572 -- and to avoid telling the interactive linker to link them.
573 do debugTraceMsg dflags 2 "Upsweep partially successful."
576 = map ms_mod modsDone
577 let mods_to_zap_names
578 = findPartiallyCompletedCycles modsDone_names
581 = filter ((`notElem` mods_to_zap_names).ms_mod)
584 let hpt4 = retainInTopLevelEnvs (map ms_mod mods_to_keep)
587 -- Clean up after ourselves
588 cleanTempFilesExcept dflags (ppFilesFromSummaries mods_to_keep)
590 -- there should be no Nothings where linkables should be, now
591 ASSERT(all (isJust.hm_linkable)
592 (moduleEnvElts (hsc_HPT hsc_env))) do
594 -- Link everything together
595 linkresult <- link ghci_mode dflags False hpt4
597 let hsc_env4 = hsc_env1{ hsc_HPT = hpt4 }
598 loadFinish Failed linkresult ref hsc_env4
600 -- Finish up after a load.
602 -- If the link failed, unload everything and return.
603 loadFinish all_ok Failed ref hsc_env
604 = do unload hsc_env []
605 writeIORef ref $! discardProg hsc_env
608 -- Empty the interactive context and set the module context to the topmost
609 -- newly loaded module, or the Prelude if none were loaded.
610 loadFinish all_ok Succeeded ref hsc_env
611 = do writeIORef ref $! hsc_env{ hsc_IC = emptyInteractiveContext }
615 -- Forget the current program, but retain the persistent info in HscEnv
616 discardProg :: HscEnv -> HscEnv
618 = hsc_env { hsc_mod_graph = emptyMG,
619 hsc_IC = emptyInteractiveContext,
620 hsc_HPT = emptyHomePackageTable }
622 -- used to fish out the preprocess output files for the purposes of
623 -- cleaning up. The preprocessed file *might* be the same as the
624 -- source file, but that doesn't do any harm.
625 ppFilesFromSummaries summaries = [ fn | Just fn <- map ms_hspp_file summaries ]
627 -- -----------------------------------------------------------------------------
631 CheckedModule { parsedSource :: ParsedSource,
632 -- ToDo: renamedSource
633 typecheckedSource :: Maybe TypecheckedSource,
634 checkedModuleInfo :: Maybe ModuleInfo
637 type ParsedSource = Located (HsModule RdrName)
638 type TypecheckedSource = LHsBinds Id
640 -- | This is the way to get access to parsed and typechecked source code
641 -- for a module. 'checkModule' loads all the dependencies of the specified
642 -- module in the Session, and then attempts to typecheck the module. If
643 -- successful, it returns the abstract syntax for the module.
644 checkModule :: Session -> Module -> (Messages -> IO ())
645 -> IO (Maybe CheckedModule)
646 checkModule session@(Session ref) mod msg_act = do
647 -- load up the dependencies first
648 r <- loadMsgs session (LoadDependenciesOf mod) msg_act
649 if (failed r) then return Nothing else do
651 -- now parse & typecheck the module
652 hsc_env <- readIORef ref
653 let mg = hsc_mod_graph hsc_env
654 case [ ms | ms <- mg, ms_mod ms == mod ] of
657 -- Add in the OPTIONS from the source file This is nasty:
658 -- we've done this once already, in the compilation manager
659 -- It might be better to cache the flags in the
660 -- ml_hspp_file field, say
661 let dflags0 = hsc_dflags hsc_env
662 hspp_buf = expectJust "GHC.checkModule" (ms_hspp_buf ms)
663 opts = getOptionsFromStringBuffer hspp_buf
664 (dflags1,leftovers) <- parseDynamicFlags dflags0 (map snd opts)
665 if (not (null leftovers))
666 then do let filename = fromJust (ml_hs_file (ms_location ms))
667 msg_act (optionsErrorMsgs leftovers opts filename)
671 r <- hscFileCheck hsc_env{hsc_dflags=dflags1} msg_act ms
675 HscChecked parsed Nothing ->
676 return (Just (CheckedModule parsed Nothing Nothing))
677 HscChecked parsed (Just (tc_binds, rdr_env, details)) -> do
678 let minf = ModuleInfo {
679 minf_details = details,
680 minf_rdr_env = Just rdr_env
682 return (Just (CheckedModule {
683 parsedSource = parsed,
684 typecheckedSource = Just tc_binds,
685 checkedModuleInfo = Just minf }))
687 -- ---------------------------------------------------------------------------
690 unload :: HscEnv -> [Linkable] -> IO ()
691 unload hsc_env stable_linkables -- Unload everthing *except* 'stable_linkables'
692 = case ghcMode (hsc_dflags hsc_env) of
693 BatchCompile -> return ()
694 JustTypecheck -> return ()
696 Interactive -> Linker.unload (hsc_dflags hsc_env) stable_linkables
698 Interactive -> panic "unload: no interpreter"
700 other -> panic "unload: strange mode"
702 -- -----------------------------------------------------------------------------
706 Stability tells us which modules definitely do not need to be recompiled.
707 There are two main reasons for having stability:
709 - avoid doing a complete upsweep of the module graph in GHCi when
710 modules near the bottom of the tree have not changed.
712 - to tell GHCi when it can load object code: we can only load object code
713 for a module when we also load object code fo all of the imports of the
714 module. So we need to know that we will definitely not be recompiling
715 any of these modules, and we can use the object code.
717 NB. stability is of no importance to BatchCompile at all, only Interactive.
718 (ToDo: what about JustTypecheck?)
720 The stability check is as follows. Both stableObject and
721 stableBCO are used during the upsweep phase later.
724 stable m = stableObject m || stableBCO m
727 all stableObject (imports m)
728 && old linkable does not exist, or is == on-disk .o
729 && date(on-disk .o) > date(.hs)
732 all stable (imports m)
733 && date(BCO) > date(.hs)
736 These properties embody the following ideas:
738 - if a module is stable:
739 - if it has been compiled in a previous pass (present in HPT)
740 then it does not need to be compiled or re-linked.
741 - if it has not been compiled in a previous pass,
742 then we only need to read its .hi file from disk and
743 link it to produce a ModDetails.
745 - if a modules is not stable, we will definitely be at least
746 re-linking, and possibly re-compiling it during the upsweep.
747 All non-stable modules can (and should) therefore be unlinked
750 - Note that objects are only considered stable if they only depend
751 on other objects. We can't link object code against byte code.
755 :: HomePackageTable -- HPT from last compilation
756 -> [SCC ModSummary] -- current module graph (cyclic)
757 -> [Module] -- all home modules
758 -> ([Module], -- stableObject
759 [Module]) -- stableBCO
761 checkStability hpt sccs all_home_mods = foldl checkSCC ([],[]) sccs
763 checkSCC (stable_obj, stable_bco) scc0
764 | stableObjects = (scc_mods ++ stable_obj, stable_bco)
765 | stableBCOs = (stable_obj, scc_mods ++ stable_bco)
766 | otherwise = (stable_obj, stable_bco)
768 scc = flattenSCC scc0
769 scc_mods = map ms_mod scc
770 home_module m = m `elem` all_home_mods && m `notElem` scc_mods
772 scc_allimps = nub (filter home_module (concatMap ms_allimps scc))
773 -- all imports outside the current SCC, but in the home pkg
775 stable_obj_imps = map (`elem` stable_obj) scc_allimps
776 stable_bco_imps = map (`elem` stable_bco) scc_allimps
783 and (zipWith (||) stable_obj_imps stable_bco_imps)
787 | Just t <- ms_obj_date ms = t >= ms_hs_date ms
791 same_as_prev t = case lookupModuleEnv hpt (ms_mod ms) of
793 Just hmi | Just l <- hm_linkable hmi
794 -> isObjectLinkable l && t == linkableTime l
795 -- why '>=' rather than '>' above? If the filesystem stores
796 -- times to the nearset second, we may occasionally find that
797 -- the object & source have the same modification time,
798 -- especially if the source was automatically generated
799 -- and compiled. Using >= is slightly unsafe, but it matches
803 = case lookupModuleEnv hpt (ms_mod ms) of
805 Just hmi | Just l <- hm_linkable hmi ->
806 not (isObjectLinkable l) &&
807 linkableTime l >= ms_hs_date ms
809 ms_allimps :: ModSummary -> [Module]
810 ms_allimps ms = ms_srcimps ms ++ ms_imps ms
812 -- -----------------------------------------------------------------------------
813 -- Prune the HomePackageTable
815 -- Before doing an upsweep, we can throw away:
817 -- - For non-stable modules:
818 -- - all ModDetails, all linked code
819 -- - all unlinked code that is out of date with respect to
822 -- This is VERY IMPORTANT otherwise we'll end up requiring 2x the
823 -- space at the end of the upsweep, because the topmost ModDetails of the
824 -- old HPT holds on to the entire type environment from the previous
827 pruneHomePackageTable
830 -> ([Module],[Module])
833 pruneHomePackageTable hpt summ (stable_obj, stable_bco)
834 = mapModuleEnv prune hpt
836 | is_stable modl = hmi'
837 | otherwise = hmi'{ hm_details = emptyModDetails }
839 modl = mi_module (hm_iface hmi)
840 hmi' | Just l <- hm_linkable hmi, linkableTime l < ms_hs_date ms
841 = hmi{ hm_linkable = Nothing }
844 where ms = expectJust "prune" (lookupModuleEnv ms_map modl)
846 ms_map = mkModuleEnv [(ms_mod ms, ms) | ms <- summ]
848 is_stable m = m `elem` stable_obj || m `elem` stable_bco
850 -- -----------------------------------------------------------------------------
852 -- Return (names of) all those in modsDone who are part of a cycle
853 -- as defined by theGraph.
854 findPartiallyCompletedCycles :: [Module] -> [SCC ModSummary] -> [Module]
855 findPartiallyCompletedCycles modsDone theGraph
859 chew ((AcyclicSCC v):rest) = chew rest -- acyclic? not interesting.
860 chew ((CyclicSCC vs):rest)
861 = let names_in_this_cycle = nub (map ms_mod vs)
863 = nub ([done | done <- modsDone,
864 done `elem` names_in_this_cycle])
865 chewed_rest = chew rest
867 if notNull mods_in_this_cycle
868 && length mods_in_this_cycle < length names_in_this_cycle
869 then mods_in_this_cycle ++ chewed_rest
872 -- -----------------------------------------------------------------------------
875 -- This is where we compile each module in the module graph, in a pass
876 -- from the bottom to the top of the graph.
878 -- There better had not be any cyclic groups here -- we check for them.
881 :: HscEnv -- Includes initially-empty HPT
882 -> HomePackageTable -- HPT from last time round (pruned)
883 -> ([Module],[Module]) -- stable modules (see checkStability)
884 -> IO () -- How to clean up unwanted tmp files
885 -> (Messages -> IO ()) -- Compiler error message callback
886 -> [SCC ModSummary] -- Mods to do (the worklist)
888 HscEnv, -- With an updated HPT
889 [ModSummary]) -- Mods which succeeded
891 upsweep hsc_env old_hpt stable_mods cleanup msg_act mods
892 = upsweep' hsc_env old_hpt stable_mods cleanup msg_act mods 1 (length mods)
894 upsweep' hsc_env old_hpt stable_mods cleanup msg_act
896 = return (Succeeded, hsc_env, [])
898 upsweep' hsc_env old_hpt stable_mods cleanup msg_act
900 = do putMsg (showSDoc (cyclicModuleErr ms))
901 return (Failed, hsc_env, [])
903 upsweep' hsc_env old_hpt stable_mods cleanup msg_act
904 (AcyclicSCC mod:mods) mod_index nmods
905 = do -- putStrLn ("UPSWEEP_MOD: hpt = " ++
906 -- show (map (moduleUserString.moduleName.mi_module.hm_iface)
907 -- (moduleEnvElts (hsc_HPT hsc_env)))
909 mb_mod_info <- upsweep_mod hsc_env old_hpt stable_mods msg_act mod
912 cleanup -- Remove unwanted tmp files between compilations
915 Nothing -> return (Failed, hsc_env, [])
917 { let this_mod = ms_mod mod
919 -- Add new info to hsc_env
920 hpt1 = extendModuleEnv (hsc_HPT hsc_env)
922 hsc_env1 = hsc_env { hsc_HPT = hpt1 }
924 -- Space-saving: delete the old HPT entry
925 -- for mod BUT if mod is a hs-boot
926 -- node, don't delete it. For the
927 -- interface, the HPT entry is probaby for the
928 -- main Haskell source file. Deleting it
929 -- would force .. (what?? --SDM)
930 old_hpt1 | isBootSummary mod = old_hpt
931 | otherwise = delModuleEnv old_hpt this_mod
933 ; (restOK, hsc_env2, modOKs)
934 <- upsweep' hsc_env1 old_hpt1 stable_mods cleanup
935 msg_act mods (mod_index+1) nmods
936 ; return (restOK, hsc_env2, mod:modOKs)
940 -- Compile a single module. Always produce a Linkable for it if
941 -- successful. If no compilation happened, return the old Linkable.
942 upsweep_mod :: HscEnv
944 -> ([Module],[Module])
945 -> (Messages -> IO ())
947 -> Int -- index of module
948 -> Int -- total number of modules
949 -> IO (Maybe HomeModInfo) -- Nothing => Failed
951 upsweep_mod hsc_env old_hpt (stable_obj, stable_bco) msg_act summary mod_index nmods
954 this_mod = ms_mod summary
955 mb_obj_date = ms_obj_date summary
956 obj_fn = ml_obj_file (ms_location summary)
957 hs_date = ms_hs_date summary
959 compile_it :: Maybe Linkable -> IO (Maybe HomeModInfo)
960 compile_it = upsweep_compile hsc_env old_hpt this_mod
961 msg_act summary mod_index nmods
963 case ghcMode (hsc_dflags hsc_env) of
966 -- Batch-compilating is easy: just check whether we have
967 -- an up-to-date object file. If we do, then the compiler
968 -- needs to do a recompilation check.
969 _ | Just obj_date <- mb_obj_date, obj_date >= hs_date -> do
971 findObjectLinkable this_mod obj_fn obj_date
972 compile_it (Just linkable)
979 _ | is_stable_obj, isJust old_hmi ->
981 -- object is stable, and we have an entry in the
982 -- old HPT: nothing to do
984 | is_stable_obj, isNothing old_hmi -> do
986 findObjectLinkable this_mod obj_fn
987 (expectJust "upseep1" mb_obj_date)
988 compile_it (Just linkable)
989 -- object is stable, but we need to load the interface
990 -- off disk to make a HMI.
993 ASSERT(isJust old_hmi) -- must be in the old_hpt
995 -- BCO is stable: nothing to do
997 | Just hmi <- old_hmi,
998 Just l <- hm_linkable hmi, not (isObjectLinkable l),
999 linkableTime l >= ms_hs_date summary ->
1001 -- we have an old BCO that is up to date with respect
1002 -- to the source: do a recompilation check as normal.
1006 -- no existing code at all: we must recompile.
1008 is_stable_obj = this_mod `elem` stable_obj
1009 is_stable_bco = this_mod `elem` stable_bco
1011 old_hmi = lookupModuleEnv old_hpt this_mod
1013 -- Run hsc to compile a module
1014 upsweep_compile hsc_env old_hpt this_mod msg_act summary
1016 mb_old_linkable = do
1018 -- The old interface is ok if it's in the old HPT
1019 -- a) we're compiling a source file, and the old HPT
1020 -- entry is for a source file
1021 -- b) we're compiling a hs-boot file
1022 -- Case (b) allows an hs-boot file to get the interface of its
1023 -- real source file on the second iteration of the compilation
1024 -- manager, but that does no harm. Otherwise the hs-boot file
1025 -- will always be recompiled
1028 = case lookupModuleEnv old_hpt this_mod of
1030 Just hm_info | isBootSummary summary -> Just iface
1031 | not (mi_boot iface) -> Just iface
1032 | otherwise -> Nothing
1034 iface = hm_iface hm_info
1036 compresult <- compile hsc_env msg_act summary mb_old_linkable mb_old_iface
1040 -- Compilation failed. Compile may still have updated the PCS, tho.
1041 CompErrs -> return Nothing
1043 -- Compilation "succeeded", and may or may not have returned a new
1044 -- linkable (depending on whether compilation was actually performed
1046 CompOK new_details new_iface new_linkable
1047 -> do let new_info = HomeModInfo { hm_iface = new_iface,
1048 hm_details = new_details,
1049 hm_linkable = new_linkable }
1050 return (Just new_info)
1053 -- Filter modules in the HPT
1054 retainInTopLevelEnvs :: [Module] -> HomePackageTable -> HomePackageTable
1055 retainInTopLevelEnvs keep_these hpt
1056 = mkModuleEnv [ (mod, expectJust "retain" mb_mod_info)
1058 , let mb_mod_info = lookupModuleEnv hpt mod
1059 , isJust mb_mod_info ]
1061 -- ---------------------------------------------------------------------------
1062 -- Topological sort of the module graph
1065 :: Bool -- Drop hi-boot nodes? (see below)
1069 -- Calculate SCCs of the module graph, possibly dropping the hi-boot nodes
1070 -- The resulting list of strongly-connected-components is in topologically
1071 -- sorted order, starting with the module(s) at the bottom of the
1072 -- dependency graph (ie compile them first) and ending with the ones at
1075 -- Drop hi-boot nodes (first boolean arg)?
1077 -- False: treat the hi-boot summaries as nodes of the graph,
1078 -- so the graph must be acyclic
1080 -- True: eliminate the hi-boot nodes, and instead pretend
1081 -- the a source-import of Foo is an import of Foo
1082 -- The resulting graph has no hi-boot nodes, but can by cyclic
1084 topSortModuleGraph drop_hs_boot_nodes summaries Nothing
1085 = stronglyConnComp (fst (moduleGraphNodes drop_hs_boot_nodes summaries))
1086 topSortModuleGraph drop_hs_boot_nodes summaries (Just mod)
1087 = stronglyConnComp (map vertex_fn (reachable graph root))
1089 -- restrict the graph to just those modules reachable from
1090 -- the specified module. We do this by building a graph with
1091 -- the full set of nodes, and determining the reachable set from
1092 -- the specified node.
1093 (nodes, lookup_key) = moduleGraphNodes drop_hs_boot_nodes summaries
1094 (graph, vertex_fn, key_fn) = graphFromEdges' nodes
1096 | Just key <- lookup_key HsSrcFile mod, Just v <- key_fn key = v
1097 | otherwise = throwDyn (ProgramError "module does not exist")
1099 moduleGraphNodes :: Bool -> [ModSummary]
1100 -> ([(ModSummary, Int, [Int])], HscSource -> Module -> Maybe Int)
1101 moduleGraphNodes drop_hs_boot_nodes summaries = (nodes, lookup_key)
1103 -- Drop hs-boot nodes by using HsSrcFile as the key
1104 hs_boot_key | drop_hs_boot_nodes = HsSrcFile
1105 | otherwise = HsBootFile
1107 -- We use integers as the keys for the SCC algorithm
1108 nodes :: [(ModSummary, Int, [Int])]
1109 nodes = [(s, expectJust "topSort" (lookup_key (ms_hsc_src s) (ms_mod s)),
1110 out_edge_keys hs_boot_key (ms_srcimps s) ++
1111 out_edge_keys HsSrcFile (ms_imps s) )
1113 , not (isBootSummary s && drop_hs_boot_nodes) ]
1114 -- Drop the hi-boot ones if told to do so
1116 key_map :: NodeMap Int
1117 key_map = listToFM ([(ms_mod s, ms_hsc_src s) | s <- summaries]
1120 lookup_key :: HscSource -> Module -> Maybe Int
1121 lookup_key hs_src mod = lookupFM key_map (mod, hs_src)
1123 out_edge_keys :: HscSource -> [Module] -> [Int]
1124 out_edge_keys hi_boot ms = mapCatMaybes (lookup_key hi_boot) ms
1125 -- If we want keep_hi_boot_nodes, then we do lookup_key with
1126 -- the IsBootInterface parameter True; else False
1129 type NodeKey = (Module, HscSource) -- The nodes of the graph are
1130 type NodeMap a = FiniteMap NodeKey a -- keyed by (mod, src_file_type) pairs
1132 msKey :: ModSummary -> NodeKey
1133 msKey (ModSummary { ms_mod = mod, ms_hsc_src = boot }) = (mod,boot)
1135 emptyNodeMap :: NodeMap a
1136 emptyNodeMap = emptyFM
1138 mkNodeMap :: [ModSummary] -> NodeMap ModSummary
1139 mkNodeMap summaries = listToFM [ (msKey s, s) | s <- summaries]
1141 nodeMapElts :: NodeMap a -> [a]
1142 nodeMapElts = eltsFM
1144 -- -----------------------------------------------------------------
1145 -- The unlinked image
1147 -- The compilation manager keeps a list of compiled, but as-yet unlinked
1148 -- binaries (byte code or object code). Even when it links bytecode
1149 -- it keeps the unlinked version so it can re-link it later without
1152 type UnlinkedImage = [Linkable] -- the unlinked images (should be a set, really)
1154 findModuleLinkable_maybe :: [Linkable] -> Module -> Maybe Linkable
1155 findModuleLinkable_maybe lis mod
1156 = case [LM time nm us | LM time nm us <- lis, nm == mod] of
1159 many -> pprPanic "findModuleLinkable" (ppr mod)
1161 delModuleLinkable :: [Linkable] -> Module -> [Linkable]
1162 delModuleLinkable ls mod = [ l | l@(LM _ nm _) <- ls, nm /= mod ]
1164 -----------------------------------------------------------------------------
1165 -- Downsweep (dependency analysis)
1167 -- Chase downwards from the specified root set, returning summaries
1168 -- for all home modules encountered. Only follow source-import
1171 -- We pass in the previous collection of summaries, which is used as a
1172 -- cache to avoid recalculating a module summary if the source is
1175 -- The returned list of [ModSummary] nodes has one node for each home-package
1176 -- module, plus one for any hs-boot files. The imports of these nodes
1177 -- are all there, including the imports of non-home-package modules.
1180 -> [ModSummary] -- Old summaries
1181 -> [Module] -- Ignore dependencies on these; treat them as
1182 -- if they were package modules
1184 downsweep hsc_env old_summaries excl_mods
1185 = do rootSummaries <- mapM getRootSummary roots
1186 checkDuplicates rootSummaries
1187 loop (concatMap msDeps rootSummaries)
1188 (mkNodeMap rootSummaries)
1190 roots = hsc_targets hsc_env
1192 old_summary_map :: NodeMap ModSummary
1193 old_summary_map = mkNodeMap old_summaries
1195 getRootSummary :: Target -> IO ModSummary
1196 getRootSummary (Target (TargetFile file) maybe_buf)
1197 = do exists <- doesFileExist file
1198 if exists then summariseFile hsc_env file maybe_buf else do
1199 throwDyn (CmdLineError ("can't find file: " ++ file))
1200 getRootSummary (Target (TargetModule modl) maybe_buf)
1201 = do maybe_summary <- summarise hsc_env emptyNodeMap Nothing False
1202 modl maybe_buf excl_mods
1203 case maybe_summary of
1204 Nothing -> packageModErr modl
1207 -- In a root module, the filename is allowed to diverge from the module
1208 -- name, so we have to check that there aren't multiple root files
1209 -- defining the same module (otherwise the duplicates will be silently
1210 -- ignored, leading to confusing behaviour).
1211 checkDuplicates :: [ModSummary] -> IO ()
1212 checkDuplicates summaries = mapM_ check summaries
1217 many -> multiRootsErr modl many
1218 where modl = ms_mod summ
1220 [ expectJust "checkDup" (ml_hs_file (ms_location summ'))
1221 | summ' <- summaries, ms_mod summ' == modl ]
1223 loop :: [(FilePath,Module,IsBootInterface)]
1224 -- Work list: process these modules
1225 -> NodeMap ModSummary
1228 -- The result includes the worklist, except
1229 -- for those mentioned in the visited set
1230 loop [] done = return (nodeMapElts done)
1231 loop ((cur_path, wanted_mod, is_boot) : ss) done
1232 | key `elemFM` done = loop ss done
1233 | otherwise = do { mb_s <- summarise hsc_env old_summary_map
1234 (Just cur_path) is_boot
1235 wanted_mod Nothing excl_mods
1237 Nothing -> loop ss done
1238 Just s -> loop (msDeps s ++ ss)
1239 (addToFM done key s) }
1241 key = (wanted_mod, if is_boot then HsBootFile else HsSrcFile)
1243 msDeps :: ModSummary -> [(FilePath, -- Importing module
1244 Module, -- Imported module
1245 IsBootInterface)] -- {-# SOURCE #-} import or not
1246 -- (msDeps s) returns the dependencies of the ModSummary s.
1247 -- A wrinkle is that for a {-# SOURCE #-} import we return
1248 -- *both* the hs-boot file
1249 -- *and* the source file
1250 -- as "dependencies". That ensures that the list of all relevant
1251 -- modules always contains B.hs if it contains B.hs-boot.
1252 -- Remember, this pass isn't doing the topological sort. It's
1253 -- just gathering the list of all relevant ModSummaries
1254 msDeps s = concat [ [(f, m, True), (f,m,False)] | m <- ms_srcimps s]
1255 ++ [(f,m,False) | m <- ms_imps s]
1257 f = msHsFilePath s -- Keep the importing module for error reporting
1260 -----------------------------------------------------------------------------
1261 -- Summarising modules
1263 -- We have two types of summarisation:
1265 -- * Summarise a file. This is used for the root module(s) passed to
1266 -- cmLoadModules. The file is read, and used to determine the root
1267 -- module name. The module name may differ from the filename.
1269 -- * Summarise a module. We are given a module name, and must provide
1270 -- a summary. The finder is used to locate the file in which the module
1273 summariseFile :: HscEnv -> FilePath
1274 -> Maybe (StringBuffer,ClockTime)
1276 -- Used for Haskell source only, I think
1277 -- We know the file name, and we know it exists,
1278 -- but we don't necessarily know the module name (might differ)
1279 summariseFile hsc_env file maybe_buf
1280 = do let dflags = hsc_dflags hsc_env
1282 (dflags', hspp_fn, buf)
1283 <- preprocessFile dflags file maybe_buf
1285 (srcimps,the_imps,mod) <- getImports dflags' buf hspp_fn
1287 -- Make a ModLocation for this file
1288 location <- mkHomeModLocation dflags mod file
1290 -- Tell the Finder cache where it is, so that subsequent calls
1291 -- to findModule will find it, even if it's not on any search path
1292 addHomeModuleToFinder hsc_env mod location
1294 src_timestamp <- case maybe_buf of
1295 Just (_,t) -> return t
1296 Nothing -> getModificationTime file
1298 obj_timestamp <- modificationTimeIfExists (ml_obj_file location)
1300 return (ModSummary { ms_mod = mod, ms_hsc_src = HsSrcFile,
1301 ms_location = location,
1302 ms_hspp_file = Just hspp_fn,
1303 ms_hspp_buf = Just buf,
1304 ms_srcimps = srcimps, ms_imps = the_imps,
1305 ms_hs_date = src_timestamp,
1306 ms_obj_date = obj_timestamp })
1308 -- Summarise a module, and pick up source and timestamp.
1310 -> NodeMap ModSummary -- Map of old summaries
1311 -> Maybe FilePath -- Importing module (for error messages)
1312 -> IsBootInterface -- True <=> a {-# SOURCE #-} import
1313 -> Module -- Imported module to be summarised
1314 -> Maybe (StringBuffer, ClockTime)
1315 -> [Module] -- Modules to exclude
1316 -> IO (Maybe ModSummary) -- Its new summary
1318 summarise hsc_env old_summary_map cur_mod is_boot wanted_mod maybe_buf excl_mods
1319 | wanted_mod `elem` excl_mods
1322 | Just old_summary <- lookupFM old_summary_map (wanted_mod, hsc_src)
1323 = do -- Find its new timestamp; all the
1324 -- ModSummaries in the old map have valid ml_hs_files
1325 let location = ms_location old_summary
1326 src_fn = expectJust "summarise" (ml_hs_file location)
1328 -- return the cached summary if the source didn't change
1329 src_timestamp <- case maybe_buf of
1330 Just (_,t) -> return t
1331 Nothing -> getModificationTime src_fn
1333 if ms_hs_date old_summary == src_timestamp
1334 then do -- update the object-file timestamp
1335 obj_timestamp <- getObjTimestamp location is_boot
1336 return (Just old_summary{ ms_obj_date = obj_timestamp })
1338 -- source changed: re-summarise
1339 new_summary location src_fn maybe_buf src_timestamp
1342 = do found <- findModule hsc_env wanted_mod True {-explicit-}
1345 | not (isHomePackage pkg) -> return Nothing
1346 -- Drop external-pkg
1347 | isJust (ml_hs_file location) -> just_found location
1349 err -> noModError dflags cur_mod wanted_mod err
1352 dflags = hsc_dflags hsc_env
1354 hsc_src = if is_boot then HsBootFile else HsSrcFile
1356 just_found location = do
1357 -- Adjust location to point to the hs-boot source file,
1358 -- hi file, object file, when is_boot says so
1359 let location' | is_boot = addBootSuffixLocn location
1360 | otherwise = location
1361 src_fn = expectJust "summarise2" (ml_hs_file location')
1363 -- Check that it exists
1364 -- It might have been deleted since the Finder last found it
1365 maybe_t <- modificationTimeIfExists src_fn
1367 Nothing -> noHsFileErr cur_mod src_fn
1368 Just t -> new_summary location' src_fn Nothing t
1371 new_summary location src_fn maybe_bug src_timestamp
1373 -- Preprocess the source file and get its imports
1374 -- The dflags' contains the OPTIONS pragmas
1375 (dflags', hspp_fn, buf) <- preprocessFile dflags src_fn maybe_buf
1376 (srcimps, the_imps, mod_name) <- getImports dflags' buf hspp_fn
1378 when (mod_name /= wanted_mod) $
1379 throwDyn (ProgramError
1380 (showSDoc (text src_fn
1381 <> text ": file name does not match module name"
1382 <+> quotes (ppr mod_name))))
1384 -- Find the object timestamp, and return the summary
1385 obj_timestamp <- getObjTimestamp location is_boot
1387 return (Just ( ModSummary { ms_mod = wanted_mod,
1388 ms_hsc_src = hsc_src,
1389 ms_location = location,
1390 ms_hspp_file = Just hspp_fn,
1391 ms_hspp_buf = Just buf,
1392 ms_srcimps = srcimps,
1394 ms_hs_date = src_timestamp,
1395 ms_obj_date = obj_timestamp }))
1398 getObjTimestamp location is_boot
1399 = if is_boot then return Nothing
1400 else modificationTimeIfExists (ml_obj_file location)
1403 preprocessFile :: DynFlags -> FilePath -> Maybe (StringBuffer,ClockTime)
1404 -> IO (DynFlags, FilePath, StringBuffer)
1405 preprocessFile dflags src_fn Nothing
1407 (dflags', hspp_fn) <- preprocess dflags src_fn
1408 buf <- hGetStringBuffer hspp_fn
1409 return (dflags', hspp_fn, buf)
1411 preprocessFile dflags src_fn (Just (buf, time))
1413 -- case we bypass the preprocessing stage?
1415 local_opts = getOptionsFromStringBuffer buf
1417 (dflags', errs) <- parseDynamicFlags dflags (map snd local_opts)
1421 | Unlit _ <- startPhase src_fn = True
1422 -- note: local_opts is only required if there's no Unlit phase
1423 | dopt Opt_Cpp dflags' = True
1424 | dopt Opt_Pp dflags' = True
1427 when needs_preprocessing $
1428 ghcError (ProgramError "buffer needs preprocesing; interactive check disabled")
1430 return (dflags', src_fn, buf)
1433 -----------------------------------------------------------------------------
1435 -----------------------------------------------------------------------------
1437 noModError :: DynFlags -> Maybe FilePath -> Module -> FindResult -> IO ab
1438 -- ToDo: we don't have a proper line number for this error
1439 noModError dflags cur_mod wanted_mod err
1440 = throwDyn $ ProgramError $ showSDoc $
1441 vcat [cantFindError dflags wanted_mod err,
1442 nest 2 (parens (pp_where cur_mod))]
1444 noHsFileErr cur_mod path
1445 = throwDyn $ CmdLineError $ showSDoc $
1446 vcat [text "Can't find" <+> text path,
1447 nest 2 (parens (pp_where cur_mod))]
1449 pp_where Nothing = text "one of the roots of the dependency analysis"
1450 pp_where (Just p) = text "imported from" <+> text p
1453 = throwDyn (CmdLineError (showSDoc (text "module" <+>
1454 quotes (ppr mod) <+>
1455 text "is a package module")))
1457 multiRootsErr mod files
1458 = throwDyn (ProgramError (showSDoc (
1459 text "module" <+> quotes (ppr mod) <+>
1460 text "is defined in multiple files:" <+>
1461 sep (map text files))))
1463 cyclicModuleErr :: [ModSummary] -> SDoc
1465 = hang (ptext SLIT("Module imports form a cycle for modules:"))
1466 2 (vcat (map show_one ms))
1468 show_one ms = sep [ show_mod (ms_hsc_src ms) (ms_mod ms),
1469 nest 2 $ ptext SLIT("imports:") <+>
1470 (pp_imps HsBootFile (ms_srcimps ms)
1471 $$ pp_imps HsSrcFile (ms_imps ms))]
1472 show_mod hsc_src mod = ppr mod <> text (hscSourceString hsc_src)
1473 pp_imps src mods = fsep (map (show_mod src) mods)
1476 -- | Inform GHC that the working directory has changed. GHC will flush
1477 -- its cache of module locations, since it may no longer be valid.
1478 -- Note: if you change the working directory, you should also unload
1479 -- the current program (set targets to empty, followed by load).
1480 workingDirectoryChanged :: Session -> IO ()
1481 workingDirectoryChanged s = withSession s $ \hsc_env ->
1482 flushFinderCache (hsc_FC hsc_env)
1484 -- -----------------------------------------------------------------------------
1485 -- inspecting the session
1487 -- | Get the module dependency graph.
1488 getModuleGraph :: Session -> IO ModuleGraph -- ToDo: DiGraph ModSummary
1489 getModuleGraph s = withSession s (return . hsc_mod_graph)
1491 isLoaded :: Session -> Module -> IO Bool
1492 isLoaded s m = withSession s $ \hsc_env ->
1493 return $! isJust (lookupModuleEnv (hsc_HPT hsc_env) m)
1495 getBindings :: Session -> IO [TyThing]
1496 getBindings s = withSession s (return . nameEnvElts . ic_type_env . hsc_IC)
1498 getPrintUnqual :: Session -> IO PrintUnqualified
1499 getPrintUnqual s = withSession s (return . icPrintUnqual . hsc_IC)
1502 -- | Parses a string as an identifier, and returns the list of 'Name's that
1503 -- the identifier can refer to in the current interactive context.
1504 parseName :: Session -> String -> IO [Name]
1505 parseName s str = withSession s $ \hsc_env -> do
1506 maybe_rdr_name <- hscParseIdentifier (hsc_dflags hsc_env) str
1507 case maybe_rdr_name of
1508 Nothing -> return []
1509 Just (L _ rdr_name) -> do
1510 mb_names <- tcRnLookupRdrName hsc_env rdr_name
1512 Nothing -> return []
1513 Just ns -> return ns
1514 -- ToDo: should return error messages
1517 -- | Returns the 'TyThing' for a 'Name'. The 'Name' may refer to any
1518 -- entity known to GHC, including 'Name's defined using 'runStmt'.
1519 lookupName :: Session -> Name -> IO (Maybe TyThing)
1520 lookupName s name = withSession s $ \hsc_env -> do
1521 case lookupTypeEnv (ic_type_env (hsc_IC hsc_env)) name of
1522 Just tt -> return (Just tt)
1524 eps <- readIORef (hsc_EPS hsc_env)
1525 return $! lookupType (hsc_HPT hsc_env) (eps_PTE eps) name
1527 -- | Container for information about a 'Module'.
1528 data ModuleInfo = ModuleInfo {
1529 minf_details :: ModDetails,
1530 minf_rdr_env :: Maybe GlobalRdrEnv
1532 -- ToDo: this should really contain the ModIface too
1533 -- We don't want HomeModInfo here, because a ModuleInfo applies
1534 -- to package modules too.
1536 -- | Request information about a loaded 'Module'
1537 getModuleInfo :: Session -> Module -> IO (Maybe ModuleInfo)
1538 getModuleInfo s mdl = withSession s $ \hsc_env -> do
1539 case lookupModuleEnv (hsc_HPT hsc_env) mdl of
1540 Nothing -> return Nothing
1542 return (Just (ModuleInfo {
1543 minf_details = hm_details hmi,
1544 minf_rdr_env = mi_globals $! hm_iface hmi
1547 -- ToDo: we should be able to call getModuleInfo on a package module,
1548 -- even one that isn't loaded yet.
1550 -- | The list of top-level entities defined in a module
1551 modInfoTyThings :: ModuleInfo -> [TyThing]
1552 modInfoTyThings minf = typeEnvElts (md_types (minf_details minf))
1554 modInfoTopLevelScope :: ModuleInfo -> Maybe [Name]
1555 modInfoTopLevelScope minf
1556 = fmap (map gre_name . globalRdrEnvElts) (minf_rdr_env minf)
1558 modInfoExports :: ModuleInfo -> [Name]
1559 modInfoExports minf = nameSetToList $! (md_exports $! minf_details minf)
1561 isDictonaryId :: Id -> Bool
1563 = case tcSplitSigmaTy (idType id) of { (tvs, theta, tau) -> isDictTy tau }
1569 | BinaryCode FilePath
1571 type TypecheckedCode = HsTypecheckedGroup
1572 type RenamedCode = [HsGroup Name]
1574 -- ToDo: typechecks abstract syntax or renamed abstract syntax. Issues:
1575 -- - typechecked syntax includes extra dictionary translation and
1576 -- AbsBinds which need to be translated back into something closer to
1577 -- the original source.
1578 -- - renamed syntax currently doesn't exist in a single blob, since
1579 -- renaming and typechecking are interleaved at splice points. We'd
1580 -- need a restriction that there are no splices in the source module.
1583 -- - Data and Typeable instances for HsSyn.
1586 -- - things that aren't in the output of the renamer:
1587 -- - the export list
1591 -- - things that aren't in the output of the typechecker right now:
1592 -- - the export list
1594 -- - type signatures
1595 -- - type/data/newtype declarations
1596 -- - class declarations
1598 -- - extra things in the typechecker's output:
1599 -- - default methods are turned into top-level decls.
1600 -- - dictionary bindings
1602 -- ToDo: check for small transformations that happen to the syntax in
1603 -- the typechecker (eg. -e ==> negate e, perhaps for fromIntegral)
1605 -- ToDo: maybe use TH syntax instead of IfaceSyn? There's already a way
1606 -- to get from TyCons, Ids etc. to TH syntax (reify).
1608 -- :browse will use either lm_toplev or inspect lm_interface, depending
1609 -- on whether the module is interpreted or not.
1611 -- various abstract syntax types (perhaps IfaceBlah)
1615 -- This is for reconstructing refactored source code
1616 -- Calls the lexer repeatedly.
1617 -- ToDo: add comment tokens to token stream
1618 getTokenStream :: Session -> Module -> IO [Located Token]
1621 -- -----------------------------------------------------------------------------
1622 -- Interactive evaluation
1626 -- | Set the interactive evaluation context.
1628 -- Setting the context doesn't throw away any bindings; the bindings
1629 -- we've built up in the InteractiveContext simply move to the new
1630 -- module. They always shadow anything in scope in the current context.
1631 setContext :: Session
1632 -> [Module] -- entire top level scope of these modules
1633 -> [Module] -- exports only of these modules
1635 setContext (Session ref) toplevs exports = do
1636 hsc_env <- readIORef ref
1637 let old_ic = hsc_IC hsc_env
1638 hpt = hsc_HPT hsc_env
1640 mapM_ (checkModuleExists hsc_env hpt) exports
1641 export_env <- mkExportEnv hsc_env exports
1642 toplev_envs <- mapM (mkTopLevEnv hpt) toplevs
1643 let all_env = foldr plusGlobalRdrEnv export_env toplev_envs
1644 writeIORef ref hsc_env{ hsc_IC = old_ic { ic_toplev_scope = toplevs,
1645 ic_exports = exports,
1646 ic_rn_gbl_env = all_env } }
1648 checkModuleExists :: HscEnv -> HomePackageTable -> Module -> IO ()
1649 checkModuleExists hsc_env hpt mod =
1650 case lookupModuleEnv hpt mod of
1651 Just mod_info -> return ()
1652 _not_a_home_module -> do
1653 res <- findPackageModule hsc_env mod True
1655 Found _ _ -> return ()
1656 err -> let msg = cantFindError (hsc_dflags hsc_env) mod err in
1657 throwDyn (CmdLineError (showSDoc msg))
1659 mkTopLevEnv :: HomePackageTable -> Module -> IO GlobalRdrEnv
1660 mkTopLevEnv hpt modl
1661 = case lookupModuleEnv hpt modl of
1663 throwDyn (ProgramError ("mkTopLevEnv: not a home module "
1664 ++ showSDoc (pprModule modl)))
1666 case mi_globals (hm_iface details) of
1668 throwDyn (ProgramError ("mkTopLevEnv: not interpreted "
1669 ++ showSDoc (pprModule modl)))
1670 Just env -> return env
1672 -- | Get the interactive evaluation context, consisting of a pair of the
1673 -- set of modules from which we take the full top-level scope, and the set
1674 -- of modules from which we take just the exports respectively.
1675 getContext :: Session -> IO ([Module],[Module])
1676 getContext s = withSession s (\HscEnv{ hsc_IC=ic } ->
1677 return (ic_toplev_scope ic, ic_exports ic))
1679 -- | Returns 'True' if the specified module is interpreted, and hence has
1680 -- its full top-level scope available.
1681 moduleIsInterpreted :: Session -> Module -> IO Bool
1682 moduleIsInterpreted s modl = withSession s $ \h ->
1683 case lookupModuleEnv (hsc_HPT h) modl of
1684 Just details -> return (isJust (mi_globals (hm_iface details)))
1685 _not_a_home_module -> return False
1687 -- | Looks up an identifier in the current interactive context (for :info)
1688 {-# DEPRECATED getInfo "we should be using parseName/lookupName instead" #-}
1689 getInfo :: Session -> String -> IO [GetInfoResult]
1690 getInfo s id = withSession s $ \hsc_env -> hscGetInfo hsc_env id
1692 -- | Returns all names in scope in the current interactive context
1693 getNamesInScope :: Session -> IO [Name]
1694 getNamesInScope s = withSession s $ \hsc_env -> do
1695 return (map gre_name (globalRdrEnvElts (ic_rn_gbl_env (hsc_IC hsc_env))))
1697 -- -----------------------------------------------------------------------------
1698 -- Getting the type of an expression
1700 -- | Get the type of an expression
1701 exprType :: Session -> String -> IO (Maybe Type)
1702 exprType s expr = withSession s $ \hsc_env -> do
1703 maybe_stuff <- hscTcExpr hsc_env expr
1705 Nothing -> return Nothing
1706 Just ty -> return (Just tidy_ty)
1708 tidy_ty = tidyType emptyTidyEnv ty
1709 dflags = hsc_dflags hsc_env
1711 -- -----------------------------------------------------------------------------
1712 -- Getting the kind of a type
1714 -- | Get the kind of a type
1715 typeKind :: Session -> String -> IO (Maybe Kind)
1716 typeKind s str = withSession s $ \hsc_env -> do
1717 maybe_stuff <- hscKcType hsc_env str
1719 Nothing -> return Nothing
1720 Just kind -> return (Just kind)
1722 -----------------------------------------------------------------------------
1723 -- cmCompileExpr: compile an expression and deliver an HValue
1725 compileExpr :: Session -> String -> IO (Maybe HValue)
1726 compileExpr s expr = withSession s $ \hsc_env -> do
1727 maybe_stuff <- hscStmt hsc_env ("let __cmCompileExpr = "++expr)
1729 Nothing -> return Nothing
1730 Just (new_ic, names, hval) -> do
1732 hvals <- (unsafeCoerce# hval) :: IO [HValue]
1734 case (names,hvals) of
1735 ([n],[hv]) -> return (Just hv)
1736 _ -> panic "compileExpr"
1738 -- -----------------------------------------------------------------------------
1739 -- running a statement interactively
1742 = RunOk [Name] -- ^ names bound by this evaluation
1743 | RunFailed -- ^ statement failed compilation
1744 | RunException Exception -- ^ statement raised an exception
1746 -- | Run a statement in the current interactive context. Statemenet
1747 -- may bind multple values.
1748 runStmt :: Session -> String -> IO RunResult
1749 runStmt (Session ref) expr
1751 hsc_env <- readIORef ref
1753 -- Turn off -fwarn-unused-bindings when running a statement, to hide
1754 -- warnings about the implicit bindings we introduce.
1755 let dflags' = dopt_unset (hsc_dflags hsc_env) Opt_WarnUnusedBinds
1756 hsc_env' = hsc_env{ hsc_dflags = dflags' }
1758 maybe_stuff <- hscStmt hsc_env' expr
1761 Nothing -> return RunFailed
1762 Just (new_hsc_env, names, hval) -> do
1764 let thing_to_run = unsafeCoerce# hval :: IO [HValue]
1765 either_hvals <- sandboxIO thing_to_run
1767 case either_hvals of
1769 -- on error, keep the *old* interactive context,
1770 -- so that 'it' is not bound to something
1771 -- that doesn't exist.
1772 return (RunException e)
1775 -- Get the newly bound things, and bind them.
1776 -- Don't need to delete any shadowed bindings;
1777 -- the new ones override the old ones.
1778 extendLinkEnv (zip names hvals)
1780 writeIORef ref new_hsc_env
1781 return (RunOk names)
1784 -- We run the statement in a "sandbox" to protect the rest of the
1785 -- system from anything the expression might do. For now, this
1786 -- consists of just wrapping it in an exception handler, but see below
1787 -- for another version.
1789 sandboxIO :: IO a -> IO (Either Exception a)
1790 sandboxIO thing = Exception.try thing
1793 -- This version of sandboxIO runs the expression in a completely new
1794 -- RTS main thread. It is disabled for now because ^C exceptions
1795 -- won't be delivered to the new thread, instead they'll be delivered
1796 -- to the (blocked) GHCi main thread.
1798 -- SLPJ: when re-enabling this, reflect a wrong-stat error as an exception
1800 sandboxIO :: IO a -> IO (Either Int (Either Exception a))
1801 sandboxIO thing = do
1802 st_thing <- newStablePtr (Exception.try thing)
1803 alloca $ \ p_st_result -> do
1804 stat <- rts_evalStableIO st_thing p_st_result
1805 freeStablePtr st_thing
1807 then do st_result <- peek p_st_result
1808 result <- deRefStablePtr st_result
1809 freeStablePtr st_result
1810 return (Right result)
1812 return (Left (fromIntegral stat))
1814 foreign import "rts_evalStableIO" {- safe -}
1815 rts_evalStableIO :: StablePtr (IO a) -> Ptr (StablePtr a) -> IO CInt
1816 -- more informative than the C type!
1819 -- ---------------------------------------------------------------------------
1820 -- cmBrowseModule: get all the TyThings defined in a module
1822 {-# DEPRECATED browseModule "we should be using getModuleInfo instead" #-}
1823 browseModule :: Session -> Module -> Bool -> IO [IfaceDecl]
1824 browseModule s modl exports_only = withSession s $ \hsc_env -> do
1825 mb_decls <- getModuleContents hsc_env modl exports_only
1827 Nothing -> return [] -- An error of some kind
1828 Just ds -> return ds
1831 -----------------------------------------------------------------------------
1832 -- show a module and it's source/object filenames
1834 showModule :: Session -> ModSummary -> IO String
1835 showModule s mod_summary = withSession s $ \hsc_env -> do
1836 case lookupModuleEnv (hsc_HPT hsc_env) (ms_mod mod_summary) of
1837 Nothing -> panic "missing linkable"
1838 Just mod_info -> return (showModMsg obj_linkable mod_summary)
1840 obj_linkable = isObjectLinkable (fromJust (hm_linkable mod_info))