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,
73 -- * Abstract syntax elements
76 Module, mkModule, pprModule,
83 isImplicitId, isDeadBinder,
84 isSpecPragmaId, isExportedId, isLocalId, isGlobalId,
86 isPrimOpId, isFCallId,
87 isDataConWorkId, idDataCon,
88 isBottomingId, isDictonaryId,
90 -- ** Type constructors
92 isClassTyCon, isSynTyCon, isNewTyCon,
94 -- ** Data constructors
99 classSCTheta, classTvsFds,
101 -- ** Types and Kinds
109 module HsSyn, -- ToDo: remove extraneous bits
112 GhcException(..), showGhcException,
122 * inline bits of HscMain here to simplify layering: hscGetInfo,
124 * we need to expose DynFlags, so should parseDynamicFlags really be
125 part of this interface?
126 * what StaticFlags should we expose, if any?
129 #include "HsVersions.h"
132 import qualified Linker
133 import Linker ( HValue, extendLinkEnv )
134 import NameEnv ( lookupNameEnv )
135 import TcRnDriver ( mkExportEnv, getModuleContents, tcRnLookupRdrName )
136 import RdrName ( plusGlobalRdrEnv )
137 import HscMain ( hscGetInfo, GetInfoResult, hscParseIdentifier,
138 hscStmt, hscTcExpr, hscKcType )
139 import Type ( tidyType )
140 import VarEnv ( emptyTidyEnv )
141 import GHC.Exts ( unsafeCoerce# )
142 import IfaceSyn ( IfaceDecl )
145 import Packages ( initPackages )
146 import NameSet ( NameSet, nameSetToList )
147 import RdrName ( GlobalRdrEnv )
149 import Type ( Kind, Type, dropForAlls )
150 import Id ( Id, idType, isImplicitId, isDeadBinder,
151 isSpecPragmaId, isExportedId, isLocalId, isGlobalId,
153 isPrimOpId, isFCallId,
154 isDataConWorkId, idDataCon,
156 import TyCon ( TyCon, isClassTyCon, isSynTyCon, isNewTyCon )
157 import Class ( Class, classSCTheta, classTvsFds )
158 import DataCon ( DataCon )
159 import Name ( Name, getName, nameModule_maybe )
160 import RdrName ( RdrName, gre_name, globalRdrEnvElts )
161 import NameEnv ( nameEnvElts )
162 import SrcLoc ( Located(..), mkSrcLoc, srcLocSpan )
163 import DriverPipeline
164 import DriverPhases ( Phase(..), isHaskellSrcFilename, startPhase )
165 import GetImports ( getImports )
166 import Packages ( isHomePackage )
168 import HscMain ( newHscEnv, hscFileCheck, HscResult(..) )
172 import SysTools ( initSysTools, cleanTempFiles )
177 import ErrUtils ( showPass, Messages, putMsg, debugTraceMsg )
178 import qualified ErrUtils
180 import StringBuffer ( StringBuffer, hGetStringBuffer )
182 import SysTools ( cleanTempFilesExcept )
183 import BasicTypes ( SuccessFlag(..), succeeded, failed )
184 import Maybes ( orElse, expectJust, mapCatMaybes )
185 import TcType ( tcSplitSigmaTy, isDictTy )
186 import Bag ( unitBag, emptyBag )
187 import FastString ( mkFastString )
189 import Directory ( getModificationTime, doesFileExist )
190 import Maybe ( isJust, isNothing, fromJust, fromMaybe, catMaybes )
191 import Maybes ( expectJust )
192 import List ( partition, nub )
193 import qualified List
194 import Monad ( unless, when, foldM )
195 import System ( exitWith, ExitCode(..) )
196 import Time ( ClockTime )
197 import EXCEPTION as Exception hiding (handle)
200 import Prelude hiding (init)
202 -- -----------------------------------------------------------------------------
203 -- Exception handlers
205 -- | Install some default exception handlers and run the inner computation.
206 -- Unless you want to handle exceptions yourself, you should wrap this around
207 -- the top level of your program. The default handlers output the error
208 -- message(s) to stderr and exit cleanly.
209 defaultErrorHandler :: IO a -> IO a
210 defaultErrorHandler inner =
211 -- top-level exception handler: any unrecognised exception is a compiler bug.
212 handle (\exception -> do
215 -- an IO exception probably isn't our fault, so don't panic
216 IOException _ -> putMsg (show exception)
217 AsyncException StackOverflow ->
218 putMsg "stack overflow: use +RTS -K<size> to increase it"
219 _other -> putMsg (show (Panic (show exception)))
220 exitWith (ExitFailure 1)
223 -- all error messages are propagated as exceptions
224 handleDyn (\dyn -> do
227 PhaseFailed _ code -> exitWith code
228 Interrupted -> exitWith (ExitFailure 1)
229 _ -> do putMsg (show (dyn :: GhcException))
230 exitWith (ExitFailure 1)
234 -- | Install a default cleanup handler to remove temporary files
235 -- deposited by a GHC run. This is seperate from
236 -- 'defaultErrorHandler', because you might want to override the error
237 -- handling, but still get the ordinary cleanup behaviour.
238 defaultCleanupHandler :: DynFlags -> IO a -> IO a
239 defaultCleanupHandler dflags inner =
240 -- make sure we clean up after ourselves
241 later (unless (dopt Opt_KeepTmpFiles dflags) $
242 cleanTempFiles dflags)
243 -- exceptions will be blocked while we clean the temporary files,
244 -- so there shouldn't be any difficulty if we receive further
249 -- | Initialises GHC. This must be done /once/ only. Takes the
250 -- command-line arguments. All command-line arguments which aren't
251 -- understood by GHC will be returned.
253 init :: [String] -> IO [String]
256 installSignalHandlers
258 -- Grab the -B option if there is one
259 let (minusB_args, argv1) = partition (prefixMatch "-B") args
260 dflags0 <- initSysTools minusB_args defaultDynFlags
261 writeIORef v_initDynFlags dflags0
263 -- Parse the static flags
264 argv2 <- parseStaticFlags argv1
267 GLOBAL_VAR(v_initDynFlags, error "initDynFlags", DynFlags)
268 -- stores the DynFlags between the call to init and subsequent
269 -- calls to newSession.
271 -- | Starts a new session. A session consists of a set of loaded
272 -- modules, a set of options (DynFlags), and an interactive context.
273 -- ToDo: GhcMode should say "keep typechecked code" and\/or "keep renamed
275 newSession :: GhcMode -> IO Session
277 dflags0 <- readIORef v_initDynFlags
278 dflags <- initDynFlags dflags0
279 env <- newHscEnv dflags{ ghcMode=mode }
283 -- tmp: this breaks the abstraction, but required because DriverMkDepend
284 -- needs to call the Finder. ToDo: untangle this.
285 sessionHscEnv :: Session -> IO HscEnv
286 sessionHscEnv (Session ref) = readIORef ref
288 withSession :: Session -> (HscEnv -> IO a) -> IO a
289 withSession (Session ref) f = do h <- readIORef ref; f h
291 modifySession :: Session -> (HscEnv -> HscEnv) -> IO ()
292 modifySession (Session ref) f = do h <- readIORef ref; writeIORef ref $! f h
294 -- -----------------------------------------------------------------------------
297 -- | Grabs the DynFlags from the Session
298 getSessionDynFlags :: Session -> IO DynFlags
299 getSessionDynFlags s = withSession s (return . hsc_dflags)
301 -- | Updates the DynFlags in a Session
302 setSessionDynFlags :: Session -> DynFlags -> IO ()
303 setSessionDynFlags s dflags = modifySession s (\h -> h{ hsc_dflags = dflags })
305 -- | Messages during compilation (eg. warnings and progress messages)
306 -- are reported using this callback. By default, these messages are
307 -- printed to stderr.
308 setMsgHandler :: (String -> IO ()) -> IO ()
309 setMsgHandler = ErrUtils.setMsgHandler
311 -- -----------------------------------------------------------------------------
314 -- ToDo: think about relative vs. absolute file paths. And what
315 -- happens when the current directory changes.
317 -- | Sets the targets for this session. Each target may be a module name
318 -- or a filename. The targets correspond to the set of root modules for
319 -- the program\/library. Unloading the current program is achieved by
320 -- setting the current set of targets to be empty, followed by load.
321 setTargets :: Session -> [Target] -> IO ()
322 setTargets s targets = modifySession s (\h -> h{ hsc_targets = targets })
324 -- | returns the current set of targets
325 getTargets :: Session -> IO [Target]
326 getTargets s = withSession s (return . hsc_targets)
328 -- | Add another target
329 addTarget :: Session -> Target -> IO ()
331 = modifySession s (\h -> h{ hsc_targets = target : hsc_targets h })
334 removeTarget :: Session -> TargetId -> IO ()
335 removeTarget s target_id
336 = modifySession s (\h -> h{ hsc_targets = filter (hsc_targets h) })
338 filter targets = [ t | t@(Target id _) <- targets, id /= target_id ]
340 -- Attempts to guess what Target a string refers to. This function implements
341 -- the --make/GHCi command-line syntax for filenames:
343 -- - if the string looks like a Haskell source filename, then interpret
345 -- - if adding a .hs or .lhs suffix yields the name of an existing file,
347 -- - otherwise interpret the string as a module name
349 guessTarget :: String -> IO Target
351 | isHaskellSrcFilename file
352 = return (Target (TargetFile file) Nothing)
354 = do exists <- doesFileExist hs_file
355 if exists then return (Target (TargetFile hs_file) Nothing) else do
356 exists <- doesFileExist lhs_file
357 if exists then return (Target (TargetFile lhs_file) Nothing) else do
358 return (Target (TargetModule (mkModule file)) Nothing)
360 hs_file = file ++ ".hs"
361 lhs_file = file ++ ".lhs"
363 -- -----------------------------------------------------------------------------
364 -- Loading the program
366 -- Perform a dependency analysis starting from the current targets
367 -- and update the session with the new module graph.
368 depanal :: Session -> [Module] -> IO ()
369 depanal (Session ref) excluded_mods = do
370 hsc_env <- readIORef ref
372 dflags = hsc_dflags hsc_env
373 gmode = ghcMode (hsc_dflags hsc_env)
374 targets = hsc_targets hsc_env
375 old_graph = hsc_mod_graph hsc_env
377 showPass dflags "Chasing dependencies"
378 when (gmode == BatchCompile) $
379 debugTraceMsg dflags 1 (showSDoc (hcat [
380 text "Chasing modules from: ",
381 hcat (punctuate comma (map pprTarget targets))]))
383 graph <- downsweep hsc_env old_graph excluded_mods
384 writeIORef ref hsc_env{ hsc_mod_graph=graph }
387 -- | The result of load.
389 = LoadOk Errors -- ^ all specified targets were loaded successfully.
390 | LoadFailed Errors -- ^ not all modules were loaded.
392 type Errors = [String]
394 data ErrMsg = ErrMsg {
395 errMsgSeverity :: Severity, -- warning, error, etc.
396 errMsgSpans :: [SrcSpan],
397 errMsgShortDoc :: Doc,
398 errMsgExtraInfo :: Doc
405 | LoadDependenciesOf Module
407 -- | Try to load the program. If a Module is supplied, then just
408 -- attempt to load up to this target. If no Module is supplied,
409 -- then try to load all targets.
410 load :: Session -> LoadHowMuch -> IO SuccessFlag
411 load session how_much =
412 loadMsgs session how_much ErrUtils.printErrorsAndWarnings
414 -- | Version of 'load' that takes a callback function to be invoked
415 -- on compiler errors and warnings as they occur during compilation.
416 loadMsgs :: Session -> LoadHowMuch -> (Messages-> IO ()) -> IO SuccessFlag
417 loadMsgs s@(Session ref) how_much msg_act
419 -- Dependency analysis first. Note that this fixes the module graph:
420 -- even if we don't get a fully successful upsweep, the full module
421 -- graph is still retained in the Session. We can tell which modules
422 -- were successfully loaded by inspecting the Session's HPT.
425 hsc_env <- readIORef ref
427 let hpt1 = hsc_HPT hsc_env
428 let dflags = hsc_dflags hsc_env
429 let mod_graph = hsc_mod_graph hsc_env
431 let ghci_mode = ghcMode (hsc_dflags hsc_env) -- this never changes
432 let verb = verbosity dflags
434 -- The "bad" boot modules are the ones for which we have
435 -- B.hs-boot in the module graph, but no B.hs
436 -- The downsweep should have ensured this does not happen
438 let all_home_mods = [ms_mod s | s <- mod_graph, not (isBootSummary s)]
439 bad_boot_mods = [s | s <- mod_graph, isBootSummary s,
440 not (ms_mod s `elem` all_home_mods)]
441 ASSERT( null bad_boot_mods ) return ()
443 -- mg2_with_srcimps drops the hi-boot nodes, returning a
444 -- graph with cycles. Among other things, it is used for
445 -- backing out partially complete cycles following a failed
446 -- upsweep, and for removing from hpt all the modules
447 -- not in strict downwards closure, during calls to compile.
448 let mg2_with_srcimps :: [SCC ModSummary]
449 mg2_with_srcimps = topSortModuleGraph True mod_graph Nothing
451 -- check the stability property for each module.
452 stable_mods@(stable_obj,stable_bco)
453 | BatchCompile <- ghci_mode = ([],[])
454 | otherwise = checkStability hpt1 mg2_with_srcimps all_home_mods
456 -- prune bits of the HPT which are definitely redundant now,
458 pruned_hpt = pruneHomePackageTable hpt1
459 (flattenSCCs mg2_with_srcimps)
464 debugTraceMsg dflags 2 (showSDoc (text "Stable obj:" <+> ppr stable_obj $$
465 text "Stable BCO:" <+> ppr stable_bco))
467 -- Unload any modules which are going to be re-linked this time around.
468 let stable_linkables = [ linkable
469 | m <- stable_obj++stable_bco,
470 Just hmi <- [lookupModuleEnv pruned_hpt m],
471 Just linkable <- [hm_linkable hmi] ]
472 unload hsc_env stable_linkables
474 -- We could at this point detect cycles which aren't broken by
475 -- a source-import, and complain immediately, but it seems better
476 -- to let upsweep_mods do this, so at least some useful work gets
477 -- done before the upsweep is abandoned.
478 --hPutStrLn stderr "after tsort:\n"
479 --hPutStrLn stderr (showSDoc (vcat (map ppr mg2)))
481 -- Now do the upsweep, calling compile for each module in
482 -- turn. Final result is version 3 of everything.
484 -- Topologically sort the module graph, this time including hi-boot
485 -- nodes, and possibly just including the portion of the graph
486 -- reachable from the module specified in the 2nd argument to load.
487 -- This graph should be cycle-free.
488 -- If we're restricting the upsweep to a portion of the graph, we
489 -- also want to retain everything that is still stable.
490 let full_mg :: [SCC ModSummary]
491 full_mg = topSortModuleGraph False mod_graph Nothing
493 maybe_top_mod = case how_much of
495 LoadDependenciesOf m -> Just m
498 partial_mg0 :: [SCC ModSummary]
499 partial_mg0 = topSortModuleGraph False mod_graph maybe_top_mod
501 -- LoadDependenciesOf m: we want the upsweep to stop just
502 -- short of the specified module (unless the specified module
505 | LoadDependenciesOf mod <- how_much
506 = ASSERT( case last partial_mg0 of
507 AcyclicSCC ms -> ms_mod ms == mod; _ -> False )
508 List.init partial_mg0
514 | AcyclicSCC ms <- full_mg,
515 ms_mod ms `elem` stable_obj++stable_bco,
516 ms_mod ms `notElem` [ ms_mod ms' |
517 AcyclicSCC ms' <- partial_mg ] ]
519 mg = stable_mg ++ partial_mg
521 -- clean up between compilations
522 let cleanup = cleanTempFilesExcept dflags
523 (ppFilesFromSummaries (flattenSCCs mg2_with_srcimps))
525 (upsweep_ok, hsc_env1, modsUpswept)
526 <- upsweep (hsc_env { hsc_HPT = emptyHomePackageTable })
527 pruned_hpt stable_mods cleanup msg_act mg
529 -- Make modsDone be the summaries for each home module now
530 -- available; this should equal the domain of hpt3.
531 -- Get in in a roughly top .. bottom order (hence reverse).
533 let modsDone = reverse modsUpswept
535 -- Try and do linking in some form, depending on whether the
536 -- upsweep was completely or only partially successful.
538 if succeeded upsweep_ok
541 -- Easy; just relink it all.
542 do debugTraceMsg dflags 2 "Upsweep completely successful."
544 -- Clean up after ourselves
545 cleanTempFilesExcept dflags (ppFilesFromSummaries modsDone)
547 -- Issue a warning for the confusing case where the user
548 -- said '-o foo' but we're not going to do any linking.
549 -- We attempt linking if either (a) one of the modules is
550 -- called Main, or (b) the user said -no-hs-main, indicating
551 -- that main() is going to come from somewhere else.
553 let ofile = outputFile dflags
554 let no_hs_main = dopt Opt_NoHsMain dflags
555 let mb_main_mod = mainModIs dflags
557 main_mod = mb_main_mod `orElse` "Main"
559 = any ((==main_mod).moduleUserString.ms_mod)
561 do_linking = a_root_is_Main || no_hs_main
563 when (ghci_mode == BatchCompile && isJust ofile && not do_linking) $
564 debugTraceMsg dflags 1 ("Warning: output was redirected with -o, " ++
565 "but no output will be generated\n" ++
566 "because there is no " ++ main_mod ++ " module.")
568 -- link everything together
569 linkresult <- link ghci_mode dflags do_linking (hsc_HPT hsc_env1)
571 loadFinish Succeeded linkresult ref hsc_env1
574 -- Tricky. We need to back out the effects of compiling any
575 -- half-done cycles, both so as to clean up the top level envs
576 -- and to avoid telling the interactive linker to link them.
577 do debugTraceMsg dflags 2 "Upsweep partially successful."
580 = map ms_mod modsDone
581 let mods_to_zap_names
582 = findPartiallyCompletedCycles modsDone_names
585 = filter ((`notElem` mods_to_zap_names).ms_mod)
588 let hpt4 = retainInTopLevelEnvs (map ms_mod mods_to_keep)
591 -- Clean up after ourselves
592 cleanTempFilesExcept dflags (ppFilesFromSummaries mods_to_keep)
594 -- there should be no Nothings where linkables should be, now
595 ASSERT(all (isJust.hm_linkable)
596 (moduleEnvElts (hsc_HPT hsc_env))) do
598 -- Link everything together
599 linkresult <- link ghci_mode dflags False hpt4
601 let hsc_env4 = hsc_env1{ hsc_HPT = hpt4 }
602 loadFinish Failed linkresult ref hsc_env4
604 -- Finish up after a load.
606 -- If the link failed, unload everything and return.
607 loadFinish all_ok Failed ref hsc_env
608 = do unload hsc_env []
609 writeIORef ref $! discardProg hsc_env
612 -- Empty the interactive context and set the module context to the topmost
613 -- newly loaded module, or the Prelude if none were loaded.
614 loadFinish all_ok Succeeded ref hsc_env
615 = do writeIORef ref $! hsc_env{ hsc_IC = emptyInteractiveContext }
619 -- Forget the current program, but retain the persistent info in HscEnv
620 discardProg :: HscEnv -> HscEnv
622 = hsc_env { hsc_mod_graph = emptyMG,
623 hsc_IC = emptyInteractiveContext,
624 hsc_HPT = emptyHomePackageTable }
626 -- used to fish out the preprocess output files for the purposes of
627 -- cleaning up. The preprocessed file *might* be the same as the
628 -- source file, but that doesn't do any harm.
629 ppFilesFromSummaries summaries = [ fn | Just fn <- map ms_hspp_file summaries ]
631 -- -----------------------------------------------------------------------------
635 CheckedModule { parsedSource :: ParsedSource,
636 renamedSource :: Maybe RenamedSource,
637 typecheckedSource :: Maybe TypecheckedSource,
638 checkedModuleInfo :: Maybe ModuleInfo
641 type ParsedSource = Located (HsModule RdrName)
642 type RenamedSource = HsGroup Name
643 type TypecheckedSource = LHsBinds Id
645 -- | This is the way to get access to parsed and typechecked source code
646 -- for a module. 'checkModule' loads all the dependencies of the specified
647 -- module in the Session, and then attempts to typecheck the module. If
648 -- successful, it returns the abstract syntax for the module.
649 checkModule :: Session -> Module -> (Messages -> IO ())
650 -> IO (Maybe CheckedModule)
651 checkModule session@(Session ref) mod msg_act = do
652 -- load up the dependencies first
653 r <- loadMsgs session (LoadDependenciesOf mod) msg_act
654 if (failed r) then return Nothing else do
656 -- now parse & typecheck the module
657 hsc_env <- readIORef ref
658 let mg = hsc_mod_graph hsc_env
659 case [ ms | ms <- mg, ms_mod ms == mod ] of
662 -- Add in the OPTIONS from the source file This is nasty:
663 -- we've done this once already, in the compilation manager
664 -- It might be better to cache the flags in the
665 -- ml_hspp_file field, say
666 let dflags0 = hsc_dflags hsc_env
667 hspp_buf = expectJust "GHC.checkModule" (ms_hspp_buf ms)
668 opts = getOptionsFromStringBuffer hspp_buf
669 (dflags1,leftovers) <- parseDynamicFlags dflags0 (map snd opts)
670 if (not (null leftovers))
671 then do let filename = fromJust (ml_hs_file (ms_location ms))
672 msg_act (optionsErrorMsgs leftovers opts filename)
676 r <- hscFileCheck hsc_env{hsc_dflags=dflags1} msg_act ms
680 HscChecked parsed renamed Nothing ->
681 return (Just (CheckedModule {
682 parsedSource = parsed,
683 renamedSource = renamed,
684 typecheckedSource = Nothing,
685 checkedModuleInfo = Nothing }))
686 HscChecked parsed renamed
687 (Just (tc_binds, rdr_env, details)) -> do
688 let minf = ModuleInfo {
689 minf_details = details,
690 minf_rdr_env = Just rdr_env
692 return (Just (CheckedModule {
693 parsedSource = parsed,
694 renamedSource = renamed,
695 typecheckedSource = Just tc_binds,
696 checkedModuleInfo = Just minf }))
698 -- ---------------------------------------------------------------------------
701 unload :: HscEnv -> [Linkable] -> IO ()
702 unload hsc_env stable_linkables -- Unload everthing *except* 'stable_linkables'
703 = case ghcMode (hsc_dflags hsc_env) of
704 BatchCompile -> return ()
705 JustTypecheck -> return ()
707 Interactive -> Linker.unload (hsc_dflags hsc_env) stable_linkables
709 Interactive -> panic "unload: no interpreter"
711 other -> panic "unload: strange mode"
713 -- -----------------------------------------------------------------------------
717 Stability tells us which modules definitely do not need to be recompiled.
718 There are two main reasons for having stability:
720 - avoid doing a complete upsweep of the module graph in GHCi when
721 modules near the bottom of the tree have not changed.
723 - to tell GHCi when it can load object code: we can only load object code
724 for a module when we also load object code fo all of the imports of the
725 module. So we need to know that we will definitely not be recompiling
726 any of these modules, and we can use the object code.
728 NB. stability is of no importance to BatchCompile at all, only Interactive.
729 (ToDo: what about JustTypecheck?)
731 The stability check is as follows. Both stableObject and
732 stableBCO are used during the upsweep phase later.
735 stable m = stableObject m || stableBCO m
738 all stableObject (imports m)
739 && old linkable does not exist, or is == on-disk .o
740 && date(on-disk .o) > date(.hs)
743 all stable (imports m)
744 && date(BCO) > date(.hs)
747 These properties embody the following ideas:
749 - if a module is stable:
750 - if it has been compiled in a previous pass (present in HPT)
751 then it does not need to be compiled or re-linked.
752 - if it has not been compiled in a previous pass,
753 then we only need to read its .hi file from disk and
754 link it to produce a ModDetails.
756 - if a modules is not stable, we will definitely be at least
757 re-linking, and possibly re-compiling it during the upsweep.
758 All non-stable modules can (and should) therefore be unlinked
761 - Note that objects are only considered stable if they only depend
762 on other objects. We can't link object code against byte code.
766 :: HomePackageTable -- HPT from last compilation
767 -> [SCC ModSummary] -- current module graph (cyclic)
768 -> [Module] -- all home modules
769 -> ([Module], -- stableObject
770 [Module]) -- stableBCO
772 checkStability hpt sccs all_home_mods = foldl checkSCC ([],[]) sccs
774 checkSCC (stable_obj, stable_bco) scc0
775 | stableObjects = (scc_mods ++ stable_obj, stable_bco)
776 | stableBCOs = (stable_obj, scc_mods ++ stable_bco)
777 | otherwise = (stable_obj, stable_bco)
779 scc = flattenSCC scc0
780 scc_mods = map ms_mod scc
781 home_module m = m `elem` all_home_mods && m `notElem` scc_mods
783 scc_allimps = nub (filter home_module (concatMap ms_allimps scc))
784 -- all imports outside the current SCC, but in the home pkg
786 stable_obj_imps = map (`elem` stable_obj) scc_allimps
787 stable_bco_imps = map (`elem` stable_bco) scc_allimps
794 and (zipWith (||) stable_obj_imps stable_bco_imps)
798 | Just t <- ms_obj_date ms = t >= ms_hs_date ms
802 same_as_prev t = case lookupModuleEnv hpt (ms_mod ms) of
804 Just hmi | Just l <- hm_linkable hmi
805 -> isObjectLinkable l && t == linkableTime l
806 -- why '>=' rather than '>' above? If the filesystem stores
807 -- times to the nearset second, we may occasionally find that
808 -- the object & source have the same modification time,
809 -- especially if the source was automatically generated
810 -- and compiled. Using >= is slightly unsafe, but it matches
814 = case lookupModuleEnv hpt (ms_mod ms) of
816 Just hmi | Just l <- hm_linkable hmi ->
817 not (isObjectLinkable l) &&
818 linkableTime l >= ms_hs_date ms
820 ms_allimps :: ModSummary -> [Module]
821 ms_allimps ms = ms_srcimps ms ++ ms_imps ms
823 -- -----------------------------------------------------------------------------
824 -- Prune the HomePackageTable
826 -- Before doing an upsweep, we can throw away:
828 -- - For non-stable modules:
829 -- - all ModDetails, all linked code
830 -- - all unlinked code that is out of date with respect to
833 -- This is VERY IMPORTANT otherwise we'll end up requiring 2x the
834 -- space at the end of the upsweep, because the topmost ModDetails of the
835 -- old HPT holds on to the entire type environment from the previous
838 pruneHomePackageTable
841 -> ([Module],[Module])
844 pruneHomePackageTable hpt summ (stable_obj, stable_bco)
845 = mapModuleEnv prune hpt
847 | is_stable modl = hmi'
848 | otherwise = hmi'{ hm_details = emptyModDetails }
850 modl = mi_module (hm_iface hmi)
851 hmi' | Just l <- hm_linkable hmi, linkableTime l < ms_hs_date ms
852 = hmi{ hm_linkable = Nothing }
855 where ms = expectJust "prune" (lookupModuleEnv ms_map modl)
857 ms_map = mkModuleEnv [(ms_mod ms, ms) | ms <- summ]
859 is_stable m = m `elem` stable_obj || m `elem` stable_bco
861 -- -----------------------------------------------------------------------------
863 -- Return (names of) all those in modsDone who are part of a cycle
864 -- as defined by theGraph.
865 findPartiallyCompletedCycles :: [Module] -> [SCC ModSummary] -> [Module]
866 findPartiallyCompletedCycles modsDone theGraph
870 chew ((AcyclicSCC v):rest) = chew rest -- acyclic? not interesting.
871 chew ((CyclicSCC vs):rest)
872 = let names_in_this_cycle = nub (map ms_mod vs)
874 = nub ([done | done <- modsDone,
875 done `elem` names_in_this_cycle])
876 chewed_rest = chew rest
878 if notNull mods_in_this_cycle
879 && length mods_in_this_cycle < length names_in_this_cycle
880 then mods_in_this_cycle ++ chewed_rest
883 -- -----------------------------------------------------------------------------
886 -- This is where we compile each module in the module graph, in a pass
887 -- from the bottom to the top of the graph.
889 -- There better had not be any cyclic groups here -- we check for them.
892 :: HscEnv -- Includes initially-empty HPT
893 -> HomePackageTable -- HPT from last time round (pruned)
894 -> ([Module],[Module]) -- stable modules (see checkStability)
895 -> IO () -- How to clean up unwanted tmp files
896 -> (Messages -> IO ()) -- Compiler error message callback
897 -> [SCC ModSummary] -- Mods to do (the worklist)
899 HscEnv, -- With an updated HPT
900 [ModSummary]) -- Mods which succeeded
902 upsweep hsc_env old_hpt stable_mods cleanup msg_act mods
903 = upsweep' hsc_env old_hpt stable_mods cleanup msg_act mods 1 (length mods)
905 upsweep' hsc_env old_hpt stable_mods cleanup msg_act
907 = return (Succeeded, hsc_env, [])
909 upsweep' hsc_env old_hpt stable_mods cleanup msg_act
911 = do putMsg (showSDoc (cyclicModuleErr ms))
912 return (Failed, hsc_env, [])
914 upsweep' hsc_env old_hpt stable_mods cleanup msg_act
915 (AcyclicSCC mod:mods) mod_index nmods
916 = do -- putStrLn ("UPSWEEP_MOD: hpt = " ++
917 -- show (map (moduleUserString.moduleName.mi_module.hm_iface)
918 -- (moduleEnvElts (hsc_HPT hsc_env)))
920 mb_mod_info <- upsweep_mod hsc_env old_hpt stable_mods msg_act mod
923 cleanup -- Remove unwanted tmp files between compilations
926 Nothing -> return (Failed, hsc_env, [])
928 { let this_mod = ms_mod mod
930 -- Add new info to hsc_env
931 hpt1 = extendModuleEnv (hsc_HPT hsc_env)
933 hsc_env1 = hsc_env { hsc_HPT = hpt1 }
935 -- Space-saving: delete the old HPT entry
936 -- for mod BUT if mod is a hs-boot
937 -- node, don't delete it. For the
938 -- interface, the HPT entry is probaby for the
939 -- main Haskell source file. Deleting it
940 -- would force .. (what?? --SDM)
941 old_hpt1 | isBootSummary mod = old_hpt
942 | otherwise = delModuleEnv old_hpt this_mod
944 ; (restOK, hsc_env2, modOKs)
945 <- upsweep' hsc_env1 old_hpt1 stable_mods cleanup
946 msg_act mods (mod_index+1) nmods
947 ; return (restOK, hsc_env2, mod:modOKs)
951 -- Compile a single module. Always produce a Linkable for it if
952 -- successful. If no compilation happened, return the old Linkable.
953 upsweep_mod :: HscEnv
955 -> ([Module],[Module])
956 -> (Messages -> IO ())
958 -> Int -- index of module
959 -> Int -- total number of modules
960 -> IO (Maybe HomeModInfo) -- Nothing => Failed
962 upsweep_mod hsc_env old_hpt (stable_obj, stable_bco) msg_act summary mod_index nmods
965 this_mod = ms_mod summary
966 mb_obj_date = ms_obj_date summary
967 obj_fn = ml_obj_file (ms_location summary)
968 hs_date = ms_hs_date summary
970 compile_it :: Maybe Linkable -> IO (Maybe HomeModInfo)
971 compile_it = upsweep_compile hsc_env old_hpt this_mod
972 msg_act summary mod_index nmods
974 case ghcMode (hsc_dflags hsc_env) of
977 -- Batch-compilating is easy: just check whether we have
978 -- an up-to-date object file. If we do, then the compiler
979 -- needs to do a recompilation check.
980 _ | Just obj_date <- mb_obj_date, obj_date >= hs_date -> do
982 findObjectLinkable this_mod obj_fn obj_date
983 compile_it (Just linkable)
990 _ | is_stable_obj, isJust old_hmi ->
992 -- object is stable, and we have an entry in the
993 -- old HPT: nothing to do
995 | is_stable_obj, isNothing old_hmi -> do
997 findObjectLinkable this_mod obj_fn
998 (expectJust "upseep1" mb_obj_date)
999 compile_it (Just linkable)
1000 -- object is stable, but we need to load the interface
1001 -- off disk to make a HMI.
1004 ASSERT(isJust old_hmi) -- must be in the old_hpt
1006 -- BCO is stable: nothing to do
1008 | Just hmi <- old_hmi,
1009 Just l <- hm_linkable hmi, not (isObjectLinkable l),
1010 linkableTime l >= ms_hs_date summary ->
1012 -- we have an old BCO that is up to date with respect
1013 -- to the source: do a recompilation check as normal.
1017 -- no existing code at all: we must recompile.
1019 is_stable_obj = this_mod `elem` stable_obj
1020 is_stable_bco = this_mod `elem` stable_bco
1022 old_hmi = lookupModuleEnv old_hpt this_mod
1024 -- Run hsc to compile a module
1025 upsweep_compile hsc_env old_hpt this_mod msg_act summary
1027 mb_old_linkable = do
1029 -- The old interface is ok if it's in the old HPT
1030 -- a) we're compiling a source file, and the old HPT
1031 -- entry is for a source file
1032 -- b) we're compiling a hs-boot file
1033 -- Case (b) allows an hs-boot file to get the interface of its
1034 -- real source file on the second iteration of the compilation
1035 -- manager, but that does no harm. Otherwise the hs-boot file
1036 -- will always be recompiled
1039 = case lookupModuleEnv old_hpt this_mod of
1041 Just hm_info | isBootSummary summary -> Just iface
1042 | not (mi_boot iface) -> Just iface
1043 | otherwise -> Nothing
1045 iface = hm_iface hm_info
1047 compresult <- compile hsc_env msg_act summary mb_old_linkable mb_old_iface
1051 -- Compilation failed. Compile may still have updated the PCS, tho.
1052 CompErrs -> return Nothing
1054 -- Compilation "succeeded", and may or may not have returned a new
1055 -- linkable (depending on whether compilation was actually performed
1057 CompOK new_details new_iface new_linkable
1058 -> do let new_info = HomeModInfo { hm_iface = new_iface,
1059 hm_details = new_details,
1060 hm_linkable = new_linkable }
1061 return (Just new_info)
1064 -- Filter modules in the HPT
1065 retainInTopLevelEnvs :: [Module] -> HomePackageTable -> HomePackageTable
1066 retainInTopLevelEnvs keep_these hpt
1067 = mkModuleEnv [ (mod, expectJust "retain" mb_mod_info)
1069 , let mb_mod_info = lookupModuleEnv hpt mod
1070 , isJust mb_mod_info ]
1072 -- ---------------------------------------------------------------------------
1073 -- Topological sort of the module graph
1076 :: Bool -- Drop hi-boot nodes? (see below)
1080 -- Calculate SCCs of the module graph, possibly dropping the hi-boot nodes
1081 -- The resulting list of strongly-connected-components is in topologically
1082 -- sorted order, starting with the module(s) at the bottom of the
1083 -- dependency graph (ie compile them first) and ending with the ones at
1086 -- Drop hi-boot nodes (first boolean arg)?
1088 -- False: treat the hi-boot summaries as nodes of the graph,
1089 -- so the graph must be acyclic
1091 -- True: eliminate the hi-boot nodes, and instead pretend
1092 -- the a source-import of Foo is an import of Foo
1093 -- The resulting graph has no hi-boot nodes, but can by cyclic
1095 topSortModuleGraph drop_hs_boot_nodes summaries Nothing
1096 = stronglyConnComp (fst (moduleGraphNodes drop_hs_boot_nodes summaries))
1097 topSortModuleGraph drop_hs_boot_nodes summaries (Just mod)
1098 = stronglyConnComp (map vertex_fn (reachable graph root))
1100 -- restrict the graph to just those modules reachable from
1101 -- the specified module. We do this by building a graph with
1102 -- the full set of nodes, and determining the reachable set from
1103 -- the specified node.
1104 (nodes, lookup_key) = moduleGraphNodes drop_hs_boot_nodes summaries
1105 (graph, vertex_fn, key_fn) = graphFromEdges' nodes
1107 | Just key <- lookup_key HsSrcFile mod, Just v <- key_fn key = v
1108 | otherwise = throwDyn (ProgramError "module does not exist")
1110 moduleGraphNodes :: Bool -> [ModSummary]
1111 -> ([(ModSummary, Int, [Int])], HscSource -> Module -> Maybe Int)
1112 moduleGraphNodes drop_hs_boot_nodes summaries = (nodes, lookup_key)
1114 -- Drop hs-boot nodes by using HsSrcFile as the key
1115 hs_boot_key | drop_hs_boot_nodes = HsSrcFile
1116 | otherwise = HsBootFile
1118 -- We use integers as the keys for the SCC algorithm
1119 nodes :: [(ModSummary, Int, [Int])]
1120 nodes = [(s, expectJust "topSort" (lookup_key (ms_hsc_src s) (ms_mod s)),
1121 out_edge_keys hs_boot_key (ms_srcimps s) ++
1122 out_edge_keys HsSrcFile (ms_imps s) )
1124 , not (isBootSummary s && drop_hs_boot_nodes) ]
1125 -- Drop the hi-boot ones if told to do so
1127 key_map :: NodeMap Int
1128 key_map = listToFM ([(ms_mod s, ms_hsc_src s) | s <- summaries]
1131 lookup_key :: HscSource -> Module -> Maybe Int
1132 lookup_key hs_src mod = lookupFM key_map (mod, hs_src)
1134 out_edge_keys :: HscSource -> [Module] -> [Int]
1135 out_edge_keys hi_boot ms = mapCatMaybes (lookup_key hi_boot) ms
1136 -- If we want keep_hi_boot_nodes, then we do lookup_key with
1137 -- the IsBootInterface parameter True; else False
1140 type NodeKey = (Module, HscSource) -- The nodes of the graph are
1141 type NodeMap a = FiniteMap NodeKey a -- keyed by (mod, src_file_type) pairs
1143 msKey :: ModSummary -> NodeKey
1144 msKey (ModSummary { ms_mod = mod, ms_hsc_src = boot }) = (mod,boot)
1146 emptyNodeMap :: NodeMap a
1147 emptyNodeMap = emptyFM
1149 mkNodeMap :: [ModSummary] -> NodeMap ModSummary
1150 mkNodeMap summaries = listToFM [ (msKey s, s) | s <- summaries]
1152 nodeMapElts :: NodeMap a -> [a]
1153 nodeMapElts = eltsFM
1155 -- -----------------------------------------------------------------
1156 -- The unlinked image
1158 -- The compilation manager keeps a list of compiled, but as-yet unlinked
1159 -- binaries (byte code or object code). Even when it links bytecode
1160 -- it keeps the unlinked version so it can re-link it later without
1163 type UnlinkedImage = [Linkable] -- the unlinked images (should be a set, really)
1165 findModuleLinkable_maybe :: [Linkable] -> Module -> Maybe Linkable
1166 findModuleLinkable_maybe lis mod
1167 = case [LM time nm us | LM time nm us <- lis, nm == mod] of
1170 many -> pprPanic "findModuleLinkable" (ppr mod)
1172 delModuleLinkable :: [Linkable] -> Module -> [Linkable]
1173 delModuleLinkable ls mod = [ l | l@(LM _ nm _) <- ls, nm /= mod ]
1175 -----------------------------------------------------------------------------
1176 -- Downsweep (dependency analysis)
1178 -- Chase downwards from the specified root set, returning summaries
1179 -- for all home modules encountered. Only follow source-import
1182 -- We pass in the previous collection of summaries, which is used as a
1183 -- cache to avoid recalculating a module summary if the source is
1186 -- The returned list of [ModSummary] nodes has one node for each home-package
1187 -- module, plus one for any hs-boot files. The imports of these nodes
1188 -- are all there, including the imports of non-home-package modules.
1191 -> [ModSummary] -- Old summaries
1192 -> [Module] -- Ignore dependencies on these; treat them as
1193 -- if they were package modules
1195 downsweep hsc_env old_summaries excl_mods
1196 = do rootSummaries <- mapM getRootSummary roots
1197 checkDuplicates rootSummaries
1198 loop (concatMap msDeps rootSummaries)
1199 (mkNodeMap rootSummaries)
1201 roots = hsc_targets hsc_env
1203 old_summary_map :: NodeMap ModSummary
1204 old_summary_map = mkNodeMap old_summaries
1206 getRootSummary :: Target -> IO ModSummary
1207 getRootSummary (Target (TargetFile file) maybe_buf)
1208 = do exists <- doesFileExist file
1209 if exists then summariseFile hsc_env file maybe_buf else do
1210 throwDyn (CmdLineError ("can't find file: " ++ file))
1211 getRootSummary (Target (TargetModule modl) maybe_buf)
1212 = do maybe_summary <- summarise hsc_env emptyNodeMap Nothing False
1213 modl maybe_buf excl_mods
1214 case maybe_summary of
1215 Nothing -> packageModErr modl
1218 -- In a root module, the filename is allowed to diverge from the module
1219 -- name, so we have to check that there aren't multiple root files
1220 -- defining the same module (otherwise the duplicates will be silently
1221 -- ignored, leading to confusing behaviour).
1222 checkDuplicates :: [ModSummary] -> IO ()
1223 checkDuplicates summaries = mapM_ check summaries
1228 many -> multiRootsErr modl many
1229 where modl = ms_mod summ
1231 [ expectJust "checkDup" (ml_hs_file (ms_location summ'))
1232 | summ' <- summaries, ms_mod summ' == modl ]
1234 loop :: [(FilePath,Module,IsBootInterface)]
1235 -- Work list: process these modules
1236 -> NodeMap ModSummary
1239 -- The result includes the worklist, except
1240 -- for those mentioned in the visited set
1241 loop [] done = return (nodeMapElts done)
1242 loop ((cur_path, wanted_mod, is_boot) : ss) done
1243 | key `elemFM` done = loop ss done
1244 | otherwise = do { mb_s <- summarise hsc_env old_summary_map
1245 (Just cur_path) is_boot
1246 wanted_mod Nothing excl_mods
1248 Nothing -> loop ss done
1249 Just s -> loop (msDeps s ++ ss)
1250 (addToFM done key s) }
1252 key = (wanted_mod, if is_boot then HsBootFile else HsSrcFile)
1254 msDeps :: ModSummary -> [(FilePath, -- Importing module
1255 Module, -- Imported module
1256 IsBootInterface)] -- {-# SOURCE #-} import or not
1257 -- (msDeps s) returns the dependencies of the ModSummary s.
1258 -- A wrinkle is that for a {-# SOURCE #-} import we return
1259 -- *both* the hs-boot file
1260 -- *and* the source file
1261 -- as "dependencies". That ensures that the list of all relevant
1262 -- modules always contains B.hs if it contains B.hs-boot.
1263 -- Remember, this pass isn't doing the topological sort. It's
1264 -- just gathering the list of all relevant ModSummaries
1265 msDeps s = concat [ [(f, m, True), (f,m,False)] | m <- ms_srcimps s]
1266 ++ [(f,m,False) | m <- ms_imps s]
1268 f = msHsFilePath s -- Keep the importing module for error reporting
1271 -----------------------------------------------------------------------------
1272 -- Summarising modules
1274 -- We have two types of summarisation:
1276 -- * Summarise a file. This is used for the root module(s) passed to
1277 -- cmLoadModules. The file is read, and used to determine the root
1278 -- module name. The module name may differ from the filename.
1280 -- * Summarise a module. We are given a module name, and must provide
1281 -- a summary. The finder is used to locate the file in which the module
1284 summariseFile :: HscEnv -> FilePath
1285 -> Maybe (StringBuffer,ClockTime)
1287 -- Used for Haskell source only, I think
1288 -- We know the file name, and we know it exists,
1289 -- but we don't necessarily know the module name (might differ)
1290 summariseFile hsc_env file maybe_buf
1291 = do let dflags = hsc_dflags hsc_env
1293 (dflags', hspp_fn, buf)
1294 <- preprocessFile dflags file maybe_buf
1296 (srcimps,the_imps,mod) <- getImports dflags' buf hspp_fn
1298 -- Make a ModLocation for this file
1299 location <- mkHomeModLocation dflags mod file
1301 -- Tell the Finder cache where it is, so that subsequent calls
1302 -- to findModule will find it, even if it's not on any search path
1303 addHomeModuleToFinder hsc_env mod location
1305 src_timestamp <- case maybe_buf of
1306 Just (_,t) -> return t
1307 Nothing -> getModificationTime file
1309 obj_timestamp <- modificationTimeIfExists (ml_obj_file location)
1311 return (ModSummary { ms_mod = mod, ms_hsc_src = HsSrcFile,
1312 ms_location = location,
1313 ms_hspp_file = Just hspp_fn,
1314 ms_hspp_buf = Just buf,
1315 ms_srcimps = srcimps, ms_imps = the_imps,
1316 ms_hs_date = src_timestamp,
1317 ms_obj_date = obj_timestamp })
1319 -- Summarise a module, and pick up source and timestamp.
1321 -> NodeMap ModSummary -- Map of old summaries
1322 -> Maybe FilePath -- Importing module (for error messages)
1323 -> IsBootInterface -- True <=> a {-# SOURCE #-} import
1324 -> Module -- Imported module to be summarised
1325 -> Maybe (StringBuffer, ClockTime)
1326 -> [Module] -- Modules to exclude
1327 -> IO (Maybe ModSummary) -- Its new summary
1329 summarise hsc_env old_summary_map cur_mod is_boot wanted_mod maybe_buf excl_mods
1330 | wanted_mod `elem` excl_mods
1333 | Just old_summary <- lookupFM old_summary_map (wanted_mod, hsc_src)
1334 = do -- Find its new timestamp; all the
1335 -- ModSummaries in the old map have valid ml_hs_files
1336 let location = ms_location old_summary
1337 src_fn = expectJust "summarise" (ml_hs_file location)
1339 -- return the cached summary if the source didn't change
1340 src_timestamp <- case maybe_buf of
1341 Just (_,t) -> return t
1342 Nothing -> getModificationTime src_fn
1344 if ms_hs_date old_summary == src_timestamp
1345 then do -- update the object-file timestamp
1346 obj_timestamp <- getObjTimestamp location is_boot
1347 return (Just old_summary{ ms_obj_date = obj_timestamp })
1349 -- source changed: re-summarise
1350 new_summary location src_fn maybe_buf src_timestamp
1353 = do found <- findModule hsc_env wanted_mod True {-explicit-}
1356 | not (isHomePackage pkg) -> return Nothing
1357 -- Drop external-pkg
1358 | isJust (ml_hs_file location) -> just_found location
1360 err -> noModError dflags cur_mod wanted_mod err
1363 dflags = hsc_dflags hsc_env
1365 hsc_src = if is_boot then HsBootFile else HsSrcFile
1367 just_found location = do
1368 -- Adjust location to point to the hs-boot source file,
1369 -- hi file, object file, when is_boot says so
1370 let location' | is_boot = addBootSuffixLocn location
1371 | otherwise = location
1372 src_fn = expectJust "summarise2" (ml_hs_file location')
1374 -- Check that it exists
1375 -- It might have been deleted since the Finder last found it
1376 maybe_t <- modificationTimeIfExists src_fn
1378 Nothing -> noHsFileErr cur_mod src_fn
1379 Just t -> new_summary location' src_fn Nothing t
1382 new_summary location src_fn maybe_bug src_timestamp
1384 -- Preprocess the source file and get its imports
1385 -- The dflags' contains the OPTIONS pragmas
1386 (dflags', hspp_fn, buf) <- preprocessFile dflags src_fn maybe_buf
1387 (srcimps, the_imps, mod_name) <- getImports dflags' buf hspp_fn
1389 when (mod_name /= wanted_mod) $
1390 throwDyn (ProgramError
1391 (showSDoc (text src_fn
1392 <> text ": file name does not match module name"
1393 <+> quotes (ppr mod_name))))
1395 -- Find the object timestamp, and return the summary
1396 obj_timestamp <- getObjTimestamp location is_boot
1398 return (Just ( ModSummary { ms_mod = wanted_mod,
1399 ms_hsc_src = hsc_src,
1400 ms_location = location,
1401 ms_hspp_file = Just hspp_fn,
1402 ms_hspp_buf = Just buf,
1403 ms_srcimps = srcimps,
1405 ms_hs_date = src_timestamp,
1406 ms_obj_date = obj_timestamp }))
1409 getObjTimestamp location is_boot
1410 = if is_boot then return Nothing
1411 else modificationTimeIfExists (ml_obj_file location)
1414 preprocessFile :: DynFlags -> FilePath -> Maybe (StringBuffer,ClockTime)
1415 -> IO (DynFlags, FilePath, StringBuffer)
1416 preprocessFile dflags src_fn Nothing
1418 (dflags', hspp_fn) <- preprocess dflags src_fn
1419 buf <- hGetStringBuffer hspp_fn
1420 return (dflags', hspp_fn, buf)
1422 preprocessFile dflags src_fn (Just (buf, time))
1424 -- case we bypass the preprocessing stage?
1426 local_opts = getOptionsFromStringBuffer buf
1428 (dflags', errs) <- parseDynamicFlags dflags (map snd local_opts)
1432 | Unlit _ <- startPhase src_fn = True
1433 -- note: local_opts is only required if there's no Unlit phase
1434 | dopt Opt_Cpp dflags' = True
1435 | dopt Opt_Pp dflags' = True
1438 when needs_preprocessing $
1439 ghcError (ProgramError "buffer needs preprocesing; interactive check disabled")
1441 return (dflags', src_fn, buf)
1444 -----------------------------------------------------------------------------
1446 -----------------------------------------------------------------------------
1448 noModError :: DynFlags -> Maybe FilePath -> Module -> FindResult -> IO ab
1449 -- ToDo: we don't have a proper line number for this error
1450 noModError dflags cur_mod wanted_mod err
1451 = throwDyn $ ProgramError $ showSDoc $
1452 vcat [cantFindError dflags wanted_mod err,
1453 nest 2 (parens (pp_where cur_mod))]
1455 noHsFileErr cur_mod path
1456 = throwDyn $ CmdLineError $ showSDoc $
1457 vcat [text "Can't find" <+> text path,
1458 nest 2 (parens (pp_where cur_mod))]
1460 pp_where Nothing = text "one of the roots of the dependency analysis"
1461 pp_where (Just p) = text "imported from" <+> text p
1464 = throwDyn (CmdLineError (showSDoc (text "module" <+>
1465 quotes (ppr mod) <+>
1466 text "is a package module")))
1468 multiRootsErr mod files
1469 = throwDyn (ProgramError (showSDoc (
1470 text "module" <+> quotes (ppr mod) <+>
1471 text "is defined in multiple files:" <+>
1472 sep (map text files))))
1474 cyclicModuleErr :: [ModSummary] -> SDoc
1476 = hang (ptext SLIT("Module imports form a cycle for modules:"))
1477 2 (vcat (map show_one ms))
1479 show_one ms = sep [ show_mod (ms_hsc_src ms) (ms_mod ms),
1480 nest 2 $ ptext SLIT("imports:") <+>
1481 (pp_imps HsBootFile (ms_srcimps ms)
1482 $$ pp_imps HsSrcFile (ms_imps ms))]
1483 show_mod hsc_src mod = ppr mod <> text (hscSourceString hsc_src)
1484 pp_imps src mods = fsep (map (show_mod src) mods)
1487 -- | Inform GHC that the working directory has changed. GHC will flush
1488 -- its cache of module locations, since it may no longer be valid.
1489 -- Note: if you change the working directory, you should also unload
1490 -- the current program (set targets to empty, followed by load).
1491 workingDirectoryChanged :: Session -> IO ()
1492 workingDirectoryChanged s = withSession s $ \hsc_env ->
1493 flushFinderCache (hsc_FC hsc_env)
1495 -- -----------------------------------------------------------------------------
1496 -- inspecting the session
1498 -- | Get the module dependency graph.
1499 getModuleGraph :: Session -> IO ModuleGraph -- ToDo: DiGraph ModSummary
1500 getModuleGraph s = withSession s (return . hsc_mod_graph)
1502 isLoaded :: Session -> Module -> IO Bool
1503 isLoaded s m = withSession s $ \hsc_env ->
1504 return $! isJust (lookupModuleEnv (hsc_HPT hsc_env) m)
1506 getBindings :: Session -> IO [TyThing]
1507 getBindings s = withSession s (return . nameEnvElts . ic_type_env . hsc_IC)
1509 getPrintUnqual :: Session -> IO PrintUnqualified
1510 getPrintUnqual s = withSession s (return . icPrintUnqual . hsc_IC)
1513 -- | Parses a string as an identifier, and returns the list of 'Name's that
1514 -- the identifier can refer to in the current interactive context.
1515 parseName :: Session -> String -> IO [Name]
1516 parseName s str = withSession s $ \hsc_env -> do
1517 maybe_rdr_name <- hscParseIdentifier (hsc_dflags hsc_env) str
1518 case maybe_rdr_name of
1519 Nothing -> return []
1520 Just (L _ rdr_name) -> do
1521 mb_names <- tcRnLookupRdrName hsc_env rdr_name
1523 Nothing -> return []
1524 Just ns -> return ns
1525 -- ToDo: should return error messages
1528 -- | Returns the 'TyThing' for a 'Name'. The 'Name' may refer to any
1529 -- entity known to GHC, including 'Name's defined using 'runStmt'.
1530 lookupName :: Session -> Name -> IO (Maybe TyThing)
1531 lookupName s name = withSession s $ \hsc_env -> do
1532 case lookupTypeEnv (ic_type_env (hsc_IC hsc_env)) name of
1533 Just tt -> return (Just tt)
1535 eps <- readIORef (hsc_EPS hsc_env)
1536 return $! lookupType (hsc_HPT hsc_env) (eps_PTE eps) name
1538 -- | Container for information about a 'Module'.
1539 data ModuleInfo = ModuleInfo {
1540 minf_details :: ModDetails,
1541 minf_rdr_env :: Maybe GlobalRdrEnv
1543 -- ToDo: this should really contain the ModIface too
1544 -- We don't want HomeModInfo here, because a ModuleInfo applies
1545 -- to package modules too.
1547 -- | Request information about a loaded 'Module'
1548 getModuleInfo :: Session -> Module -> IO (Maybe ModuleInfo)
1549 getModuleInfo s mdl = withSession s $ \hsc_env -> do
1550 case lookupModuleEnv (hsc_HPT hsc_env) mdl of
1551 Nothing -> return Nothing
1553 return (Just (ModuleInfo {
1554 minf_details = hm_details hmi,
1555 minf_rdr_env = mi_globals $! hm_iface hmi
1558 -- ToDo: we should be able to call getModuleInfo on a package module,
1559 -- even one that isn't loaded yet.
1561 -- | The list of top-level entities defined in a module
1562 modInfoTyThings :: ModuleInfo -> [TyThing]
1563 modInfoTyThings minf = typeEnvElts (md_types (minf_details minf))
1565 modInfoTopLevelScope :: ModuleInfo -> Maybe [Name]
1566 modInfoTopLevelScope minf
1567 = fmap (map gre_name . globalRdrEnvElts) (minf_rdr_env minf)
1569 modInfoExports :: ModuleInfo -> [Name]
1570 modInfoExports minf = nameSetToList $! (md_exports $! minf_details minf)
1572 modInfoPrintUnqualified :: ModuleInfo -> Maybe PrintUnqualified
1573 modInfoPrintUnqualified minf = fmap unQualInScope (minf_rdr_env minf)
1575 isDictonaryId :: Id -> Bool
1577 = case tcSplitSigmaTy (idType id) of { (tvs, theta, tau) -> isDictTy tau }
1583 | BinaryCode FilePath
1585 -- ToDo: typechecks abstract syntax or renamed abstract syntax. Issues:
1586 -- - typechecked syntax includes extra dictionary translation and
1587 -- AbsBinds which need to be translated back into something closer to
1588 -- the original source.
1589 -- - renamed syntax currently doesn't exist in a single blob, since
1590 -- renaming and typechecking are interleaved at splice points. We'd
1591 -- need a restriction that there are no splices in the source module.
1594 -- - Data and Typeable instances for HsSyn.
1597 -- - things that aren't in the output of the renamer:
1598 -- - the export list
1602 -- - things that aren't in the output of the typechecker right now:
1603 -- - the export list
1605 -- - type signatures
1606 -- - type/data/newtype declarations
1607 -- - class declarations
1609 -- - extra things in the typechecker's output:
1610 -- - default methods are turned into top-level decls.
1611 -- - dictionary bindings
1613 -- ToDo: check for small transformations that happen to the syntax in
1614 -- the typechecker (eg. -e ==> negate e, perhaps for fromIntegral)
1616 -- ToDo: maybe use TH syntax instead of IfaceSyn? There's already a way
1617 -- to get from TyCons, Ids etc. to TH syntax (reify).
1619 -- :browse will use either lm_toplev or inspect lm_interface, depending
1620 -- on whether the module is interpreted or not.
1622 -- various abstract syntax types (perhaps IfaceBlah)
1626 -- This is for reconstructing refactored source code
1627 -- Calls the lexer repeatedly.
1628 -- ToDo: add comment tokens to token stream
1629 getTokenStream :: Session -> Module -> IO [Located Token]
1632 -- -----------------------------------------------------------------------------
1633 -- Interactive evaluation
1637 -- | Set the interactive evaluation context.
1639 -- Setting the context doesn't throw away any bindings; the bindings
1640 -- we've built up in the InteractiveContext simply move to the new
1641 -- module. They always shadow anything in scope in the current context.
1642 setContext :: Session
1643 -> [Module] -- entire top level scope of these modules
1644 -> [Module] -- exports only of these modules
1646 setContext (Session ref) toplevs exports = do
1647 hsc_env <- readIORef ref
1648 let old_ic = hsc_IC hsc_env
1649 hpt = hsc_HPT hsc_env
1651 mapM_ (checkModuleExists hsc_env hpt) exports
1652 export_env <- mkExportEnv hsc_env exports
1653 toplev_envs <- mapM (mkTopLevEnv hpt) toplevs
1654 let all_env = foldr plusGlobalRdrEnv export_env toplev_envs
1655 writeIORef ref hsc_env{ hsc_IC = old_ic { ic_toplev_scope = toplevs,
1656 ic_exports = exports,
1657 ic_rn_gbl_env = all_env } }
1659 checkModuleExists :: HscEnv -> HomePackageTable -> Module -> IO ()
1660 checkModuleExists hsc_env hpt mod =
1661 case lookupModuleEnv hpt mod of
1662 Just mod_info -> return ()
1663 _not_a_home_module -> do
1664 res <- findPackageModule hsc_env mod True
1666 Found _ _ -> return ()
1667 err -> let msg = cantFindError (hsc_dflags hsc_env) mod err in
1668 throwDyn (CmdLineError (showSDoc msg))
1670 mkTopLevEnv :: HomePackageTable -> Module -> IO GlobalRdrEnv
1671 mkTopLevEnv hpt modl
1672 = case lookupModuleEnv hpt modl of
1674 throwDyn (ProgramError ("mkTopLevEnv: not a home module "
1675 ++ showSDoc (pprModule modl)))
1677 case mi_globals (hm_iface details) of
1679 throwDyn (ProgramError ("mkTopLevEnv: not interpreted "
1680 ++ showSDoc (pprModule modl)))
1681 Just env -> return env
1683 -- | Get the interactive evaluation context, consisting of a pair of the
1684 -- set of modules from which we take the full top-level scope, and the set
1685 -- of modules from which we take just the exports respectively.
1686 getContext :: Session -> IO ([Module],[Module])
1687 getContext s = withSession s (\HscEnv{ hsc_IC=ic } ->
1688 return (ic_toplev_scope ic, ic_exports ic))
1690 -- | Returns 'True' if the specified module is interpreted, and hence has
1691 -- its full top-level scope available.
1692 moduleIsInterpreted :: Session -> Module -> IO Bool
1693 moduleIsInterpreted s modl = withSession s $ \h ->
1694 case lookupModuleEnv (hsc_HPT h) modl of
1695 Just details -> return (isJust (mi_globals (hm_iface details)))
1696 _not_a_home_module -> return False
1698 -- | Looks up an identifier in the current interactive context (for :info)
1699 {-# DEPRECATED getInfo "we should be using parseName/lookupName instead" #-}
1700 getInfo :: Session -> String -> IO [GetInfoResult]
1701 getInfo s id = withSession s $ \hsc_env -> hscGetInfo hsc_env id
1703 -- | Returns all names in scope in the current interactive context
1704 getNamesInScope :: Session -> IO [Name]
1705 getNamesInScope s = withSession s $ \hsc_env -> do
1706 return (map gre_name (globalRdrEnvElts (ic_rn_gbl_env (hsc_IC hsc_env))))
1708 -- -----------------------------------------------------------------------------
1709 -- Getting the type of an expression
1711 -- | Get the type of an expression
1712 exprType :: Session -> String -> IO (Maybe Type)
1713 exprType s expr = withSession s $ \hsc_env -> do
1714 maybe_stuff <- hscTcExpr hsc_env expr
1716 Nothing -> return Nothing
1717 Just ty -> return (Just tidy_ty)
1719 tidy_ty = tidyType emptyTidyEnv ty
1720 dflags = hsc_dflags hsc_env
1722 -- -----------------------------------------------------------------------------
1723 -- Getting the kind of a type
1725 -- | Get the kind of a type
1726 typeKind :: Session -> String -> IO (Maybe Kind)
1727 typeKind s str = withSession s $ \hsc_env -> do
1728 maybe_stuff <- hscKcType hsc_env str
1730 Nothing -> return Nothing
1731 Just kind -> return (Just kind)
1733 -----------------------------------------------------------------------------
1734 -- cmCompileExpr: compile an expression and deliver an HValue
1736 compileExpr :: Session -> String -> IO (Maybe HValue)
1737 compileExpr s expr = withSession s $ \hsc_env -> do
1738 maybe_stuff <- hscStmt hsc_env ("let __cmCompileExpr = "++expr)
1740 Nothing -> return Nothing
1741 Just (new_ic, names, hval) -> do
1743 hvals <- (unsafeCoerce# hval) :: IO [HValue]
1745 case (names,hvals) of
1746 ([n],[hv]) -> return (Just hv)
1747 _ -> panic "compileExpr"
1749 -- -----------------------------------------------------------------------------
1750 -- running a statement interactively
1753 = RunOk [Name] -- ^ names bound by this evaluation
1754 | RunFailed -- ^ statement failed compilation
1755 | RunException Exception -- ^ statement raised an exception
1757 -- | Run a statement in the current interactive context. Statemenet
1758 -- may bind multple values.
1759 runStmt :: Session -> String -> IO RunResult
1760 runStmt (Session ref) expr
1762 hsc_env <- readIORef ref
1764 -- Turn off -fwarn-unused-bindings when running a statement, to hide
1765 -- warnings about the implicit bindings we introduce.
1766 let dflags' = dopt_unset (hsc_dflags hsc_env) Opt_WarnUnusedBinds
1767 hsc_env' = hsc_env{ hsc_dflags = dflags' }
1769 maybe_stuff <- hscStmt hsc_env' expr
1772 Nothing -> return RunFailed
1773 Just (new_hsc_env, names, hval) -> do
1775 let thing_to_run = unsafeCoerce# hval :: IO [HValue]
1776 either_hvals <- sandboxIO thing_to_run
1778 case either_hvals of
1780 -- on error, keep the *old* interactive context,
1781 -- so that 'it' is not bound to something
1782 -- that doesn't exist.
1783 return (RunException e)
1786 -- Get the newly bound things, and bind them.
1787 -- Don't need to delete any shadowed bindings;
1788 -- the new ones override the old ones.
1789 extendLinkEnv (zip names hvals)
1791 writeIORef ref new_hsc_env
1792 return (RunOk names)
1795 -- We run the statement in a "sandbox" to protect the rest of the
1796 -- system from anything the expression might do. For now, this
1797 -- consists of just wrapping it in an exception handler, but see below
1798 -- for another version.
1800 sandboxIO :: IO a -> IO (Either Exception a)
1801 sandboxIO thing = Exception.try thing
1804 -- This version of sandboxIO runs the expression in a completely new
1805 -- RTS main thread. It is disabled for now because ^C exceptions
1806 -- won't be delivered to the new thread, instead they'll be delivered
1807 -- to the (blocked) GHCi main thread.
1809 -- SLPJ: when re-enabling this, reflect a wrong-stat error as an exception
1811 sandboxIO :: IO a -> IO (Either Int (Either Exception a))
1812 sandboxIO thing = do
1813 st_thing <- newStablePtr (Exception.try thing)
1814 alloca $ \ p_st_result -> do
1815 stat <- rts_evalStableIO st_thing p_st_result
1816 freeStablePtr st_thing
1818 then do st_result <- peek p_st_result
1819 result <- deRefStablePtr st_result
1820 freeStablePtr st_result
1821 return (Right result)
1823 return (Left (fromIntegral stat))
1825 foreign import "rts_evalStableIO" {- safe -}
1826 rts_evalStableIO :: StablePtr (IO a) -> Ptr (StablePtr a) -> IO CInt
1827 -- more informative than the C type!
1830 -- ---------------------------------------------------------------------------
1831 -- cmBrowseModule: get all the TyThings defined in a module
1833 {-# DEPRECATED browseModule "we should be using getModuleInfo instead" #-}
1834 browseModule :: Session -> Module -> Bool -> IO [IfaceDecl]
1835 browseModule s modl exports_only = withSession s $ \hsc_env -> do
1836 mb_decls <- getModuleContents hsc_env modl exports_only
1838 Nothing -> return [] -- An error of some kind
1839 Just ds -> return ds
1842 -----------------------------------------------------------------------------
1843 -- show a module and it's source/object filenames
1845 showModule :: Session -> ModSummary -> IO String
1846 showModule s mod_summary = withSession s $ \hsc_env -> do
1847 case lookupModuleEnv (hsc_HPT hsc_env) (ms_mod mod_summary) of
1848 Nothing -> panic "missing linkable"
1849 Just mod_info -> return (showModMsg obj_linkable mod_summary)
1851 obj_linkable = isObjectLinkable (fromJust (hm_linkable mod_info))