1 -- -----------------------------------------------------------------------------
3 -- (c) The University of Glasgow, 2005
7 -- -----------------------------------------------------------------------------
13 defaultCleanupHandler,
17 -- * Flags and settings
18 DynFlags(..), DynFlag(..), GhcMode(..), HscTarget(..), dopt,
26 Target(..), TargetId(..), Phase,
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,
54 modInfoIsExportedName,
58 -- * Interactive evaluation
59 getBindings, getPrintUnqual,
61 setContext, getContext,
64 getInfo, GetInfoResult,
76 -- * Abstract syntax elements
79 Module, mkModule, pprModule,
86 isImplicitId, isDeadBinder,
87 isSpecPragmaId, isExportedId, isLocalId, isGlobalId,
89 isPrimOpId, isFCallId,
90 isDataConWorkId, idDataCon,
91 isBottomingId, isDictonaryId,
93 -- ** Type constructors
95 isClassTyCon, isSynTyCon, isNewTyCon,
97 -- ** Data constructors
102 classSCTheta, classTvsFds,
104 -- ** Types and Kinds
112 module HsSyn, -- ToDo: remove extraneous bits
115 GhcException(..), showGhcException,
125 * inline bits of HscMain here to simplify layering: hscGetInfo,
127 * we need to expose DynFlags, so should parseDynamicFlags really be
128 part of this interface?
129 * what StaticFlags should we expose, if any?
132 #include "HsVersions.h"
135 import qualified Linker
136 import Linker ( HValue, extendLinkEnv )
137 import NameEnv ( lookupNameEnv )
138 import TcRnDriver ( getModuleContents, tcRnLookupRdrName,
140 import RdrName ( plusGlobalRdrEnv, Provenance(..), ImportSpec(..),
141 emptyGlobalRdrEnv, mkGlobalRdrEnv )
142 import HscMain ( hscGetInfo, GetInfoResult, hscParseIdentifier,
143 hscStmt, hscTcExpr, hscKcType )
144 import Type ( tidyType )
145 import VarEnv ( emptyTidyEnv )
146 import GHC.Exts ( unsafeCoerce# )
147 import IfaceSyn ( IfaceDecl )
148 import Name ( getName, nameModule_maybe )
149 import SrcLoc ( mkSrcLoc, srcLocSpan, interactiveSrcLoc )
150 import Bag ( unitBag, emptyBag )
153 import Packages ( initPackages )
154 import NameSet ( NameSet, nameSetToList, elemNameSet )
155 import RdrName ( GlobalRdrEnv, GlobalRdrElt(..), RdrName, gre_name,
158 import Type ( Kind, Type, dropForAlls )
159 import Id ( Id, idType, isImplicitId, isDeadBinder,
160 isSpecPragmaId, isExportedId, isLocalId, isGlobalId,
162 isPrimOpId, isFCallId,
163 isDataConWorkId, idDataCon,
165 import TyCon ( TyCon, isClassTyCon, isSynTyCon, isNewTyCon )
166 import Class ( Class, classSCTheta, classTvsFds )
167 import DataCon ( DataCon )
168 import Name ( Name, nameModule )
169 import NameEnv ( nameEnvElts )
170 import SrcLoc ( Located(..) )
171 import DriverPipeline
172 import DriverPhases ( Phase(..), isHaskellSrcFilename, startPhase )
173 import GetImports ( getImports )
174 import Packages ( isHomePackage )
176 import HscMain ( newHscEnv, hscFileCheck, HscResult(..) )
180 import SysTools ( initSysTools, cleanTempFiles )
185 import ErrUtils ( showPass, Messages, putMsg, debugTraceMsg )
186 import qualified ErrUtils
188 import StringBuffer ( StringBuffer, hGetStringBuffer )
190 import SysTools ( cleanTempFilesExcept )
191 import BasicTypes ( SuccessFlag(..), succeeded, failed )
192 import Maybes ( orElse, expectJust, mapCatMaybes )
193 import TcType ( tcSplitSigmaTy, isDictTy )
194 import FastString ( mkFastString )
196 import Directory ( getModificationTime, doesFileExist )
197 import Maybe ( isJust, isNothing, fromJust, fromMaybe, catMaybes )
198 import Maybes ( expectJust )
199 import List ( partition, nub )
200 import qualified List
201 import Monad ( unless, when, foldM )
202 import System ( exitWith, ExitCode(..) )
203 import Time ( ClockTime )
204 import EXCEPTION as Exception hiding (handle)
207 import Prelude hiding (init)
209 -- -----------------------------------------------------------------------------
210 -- Exception handlers
212 -- | Install some default exception handlers and run the inner computation.
213 -- Unless you want to handle exceptions yourself, you should wrap this around
214 -- the top level of your program. The default handlers output the error
215 -- message(s) to stderr and exit cleanly.
216 defaultErrorHandler :: IO a -> IO a
217 defaultErrorHandler inner =
218 -- top-level exception handler: any unrecognised exception is a compiler bug.
219 handle (\exception -> do
222 -- an IO exception probably isn't our fault, so don't panic
223 IOException _ -> putMsg (show exception)
224 AsyncException StackOverflow ->
225 putMsg "stack overflow: use +RTS -K<size> to increase it"
226 _other -> putMsg (show (Panic (show exception)))
227 exitWith (ExitFailure 1)
230 -- all error messages are propagated as exceptions
231 handleDyn (\dyn -> do
234 PhaseFailed _ code -> exitWith code
235 Interrupted -> exitWith (ExitFailure 1)
236 _ -> do putMsg (show (dyn :: GhcException))
237 exitWith (ExitFailure 1)
241 -- | Install a default cleanup handler to remove temporary files
242 -- deposited by a GHC run. This is seperate from
243 -- 'defaultErrorHandler', because you might want to override the error
244 -- handling, but still get the ordinary cleanup behaviour.
245 defaultCleanupHandler :: DynFlags -> IO a -> IO a
246 defaultCleanupHandler dflags inner =
247 -- make sure we clean up after ourselves
248 later (unless (dopt Opt_KeepTmpFiles dflags) $
249 cleanTempFiles dflags)
250 -- exceptions will be blocked while we clean the temporary files,
251 -- so there shouldn't be any difficulty if we receive further
256 -- | Initialises GHC. This must be done /once/ only. Takes the
257 -- command-line arguments. All command-line arguments which aren't
258 -- understood by GHC will be returned.
260 init :: [String] -> IO [String]
263 installSignalHandlers
265 -- Grab the -B option if there is one
266 let (minusB_args, argv1) = partition (prefixMatch "-B") args
267 dflags0 <- initSysTools minusB_args defaultDynFlags
268 writeIORef v_initDynFlags dflags0
270 -- Parse the static flags
271 argv2 <- parseStaticFlags argv1
274 GLOBAL_VAR(v_initDynFlags, error "initDynFlags", DynFlags)
275 -- stores the DynFlags between the call to init and subsequent
276 -- calls to newSession.
278 -- | Starts a new session. A session consists of a set of loaded
279 -- modules, a set of options (DynFlags), and an interactive context.
280 -- ToDo: GhcMode should say "keep typechecked code" and\/or "keep renamed
282 newSession :: GhcMode -> IO Session
284 dflags0 <- readIORef v_initDynFlags
285 dflags <- initDynFlags dflags0
286 env <- newHscEnv dflags{ ghcMode=mode }
290 -- tmp: this breaks the abstraction, but required because DriverMkDepend
291 -- needs to call the Finder. ToDo: untangle this.
292 sessionHscEnv :: Session -> IO HscEnv
293 sessionHscEnv (Session ref) = readIORef ref
295 withSession :: Session -> (HscEnv -> IO a) -> IO a
296 withSession (Session ref) f = do h <- readIORef ref; f h
298 modifySession :: Session -> (HscEnv -> HscEnv) -> IO ()
299 modifySession (Session ref) f = do h <- readIORef ref; writeIORef ref $! f h
301 -- -----------------------------------------------------------------------------
304 -- | Grabs the DynFlags from the Session
305 getSessionDynFlags :: Session -> IO DynFlags
306 getSessionDynFlags s = withSession s (return . hsc_dflags)
308 -- | Updates the DynFlags in a Session
309 setSessionDynFlags :: Session -> DynFlags -> IO ()
310 setSessionDynFlags s dflags = modifySession s (\h -> h{ hsc_dflags = dflags })
312 -- | Messages during compilation (eg. warnings and progress messages)
313 -- are reported using this callback. By default, these messages are
314 -- printed to stderr.
315 setMsgHandler :: (String -> IO ()) -> IO ()
316 setMsgHandler = ErrUtils.setMsgHandler
318 -- -----------------------------------------------------------------------------
321 -- ToDo: think about relative vs. absolute file paths. And what
322 -- happens when the current directory changes.
324 -- | Sets the targets for this session. Each target may be a module name
325 -- or a filename. The targets correspond to the set of root modules for
326 -- the program\/library. Unloading the current program is achieved by
327 -- setting the current set of targets to be empty, followed by load.
328 setTargets :: Session -> [Target] -> IO ()
329 setTargets s targets = modifySession s (\h -> h{ hsc_targets = targets })
331 -- | returns the current set of targets
332 getTargets :: Session -> IO [Target]
333 getTargets s = withSession s (return . hsc_targets)
335 -- | Add another target
336 addTarget :: Session -> Target -> IO ()
338 = modifySession s (\h -> h{ hsc_targets = target : hsc_targets h })
341 removeTarget :: Session -> TargetId -> IO ()
342 removeTarget s target_id
343 = modifySession s (\h -> h{ hsc_targets = filter (hsc_targets h) })
345 filter targets = [ t | t@(Target id _) <- targets, id /= target_id ]
347 -- Attempts to guess what Target a string refers to. This function implements
348 -- the --make/GHCi command-line syntax for filenames:
350 -- - if the string looks like a Haskell source filename, then interpret
352 -- - if adding a .hs or .lhs suffix yields the name of an existing file,
354 -- - otherwise interpret the string as a module name
356 guessTarget :: String -> Maybe Phase -> IO Target
357 guessTarget file (Just phase)
358 = return (Target (TargetFile file (Just phase)) Nothing)
359 guessTarget file Nothing
360 | isHaskellSrcFilename file
361 = return (Target (TargetFile file Nothing) Nothing)
363 = do exists <- doesFileExist hs_file
365 then return (Target (TargetFile hs_file Nothing) Nothing)
367 exists <- doesFileExist lhs_file
369 then return (Target (TargetFile lhs_file Nothing) Nothing)
371 return (Target (TargetModule (mkModule file)) Nothing)
373 hs_file = file `joinFileExt` "hs"
374 lhs_file = file `joinFileExt` "lhs"
376 -- -----------------------------------------------------------------------------
377 -- Loading the program
379 -- Perform a dependency analysis starting from the current targets
380 -- and update the session with the new module graph.
381 depanal :: Session -> [Module] -> IO ()
382 depanal (Session ref) excluded_mods = do
383 hsc_env <- readIORef ref
385 dflags = hsc_dflags hsc_env
386 gmode = ghcMode (hsc_dflags hsc_env)
387 targets = hsc_targets hsc_env
388 old_graph = hsc_mod_graph hsc_env
390 showPass dflags "Chasing dependencies"
391 when (gmode == BatchCompile) $
392 debugTraceMsg dflags 1 (showSDoc (hcat [
393 text "Chasing modules from: ",
394 hcat (punctuate comma (map pprTarget targets))]))
396 graph <- downsweep hsc_env old_graph excluded_mods
397 writeIORef ref hsc_env{ hsc_mod_graph=graph }
400 -- | The result of load.
402 = LoadOk Errors -- ^ all specified targets were loaded successfully.
403 | LoadFailed Errors -- ^ not all modules were loaded.
405 type Errors = [String]
407 data ErrMsg = ErrMsg {
408 errMsgSeverity :: Severity, -- warning, error, etc.
409 errMsgSpans :: [SrcSpan],
410 errMsgShortDoc :: Doc,
411 errMsgExtraInfo :: Doc
418 | LoadDependenciesOf Module
420 -- | Try to load the program. If a Module is supplied, then just
421 -- attempt to load up to this target. If no Module is supplied,
422 -- then try to load all targets.
423 load :: Session -> LoadHowMuch -> IO SuccessFlag
424 load session how_much =
425 loadMsgs session how_much ErrUtils.printErrorsAndWarnings
427 -- | Version of 'load' that takes a callback function to be invoked
428 -- on compiler errors and warnings as they occur during compilation.
429 loadMsgs :: Session -> LoadHowMuch -> (Messages-> IO ()) -> IO SuccessFlag
430 loadMsgs s@(Session ref) how_much msg_act
432 -- Dependency analysis first. Note that this fixes the module graph:
433 -- even if we don't get a fully successful upsweep, the full module
434 -- graph is still retained in the Session. We can tell which modules
435 -- were successfully loaded by inspecting the Session's HPT.
438 hsc_env <- readIORef ref
440 let hpt1 = hsc_HPT hsc_env
441 let dflags = hsc_dflags hsc_env
442 let mod_graph = hsc_mod_graph hsc_env
444 let ghci_mode = ghcMode (hsc_dflags hsc_env) -- this never changes
445 let verb = verbosity dflags
447 -- The "bad" boot modules are the ones for which we have
448 -- B.hs-boot in the module graph, but no B.hs
449 -- The downsweep should have ensured this does not happen
451 let all_home_mods = [ms_mod s | s <- mod_graph, not (isBootSummary s)]
452 bad_boot_mods = [s | s <- mod_graph, isBootSummary s,
453 not (ms_mod s `elem` all_home_mods)]
454 ASSERT( null bad_boot_mods ) return ()
456 -- mg2_with_srcimps drops the hi-boot nodes, returning a
457 -- graph with cycles. Among other things, it is used for
458 -- backing out partially complete cycles following a failed
459 -- upsweep, and for removing from hpt all the modules
460 -- not in strict downwards closure, during calls to compile.
461 let mg2_with_srcimps :: [SCC ModSummary]
462 mg2_with_srcimps = topSortModuleGraph True mod_graph Nothing
464 -- check the stability property for each module.
465 stable_mods@(stable_obj,stable_bco)
466 | BatchCompile <- ghci_mode = ([],[])
467 | otherwise = checkStability hpt1 mg2_with_srcimps all_home_mods
469 -- prune bits of the HPT which are definitely redundant now,
471 pruned_hpt = pruneHomePackageTable hpt1
472 (flattenSCCs mg2_with_srcimps)
477 debugTraceMsg dflags 2 (showSDoc (text "Stable obj:" <+> ppr stable_obj $$
478 text "Stable BCO:" <+> ppr stable_bco))
480 -- Unload any modules which are going to be re-linked this time around.
481 let stable_linkables = [ linkable
482 | m <- stable_obj++stable_bco,
483 Just hmi <- [lookupModuleEnv pruned_hpt m],
484 Just linkable <- [hm_linkable hmi] ]
485 unload hsc_env stable_linkables
487 -- We could at this point detect cycles which aren't broken by
488 -- a source-import, and complain immediately, but it seems better
489 -- to let upsweep_mods do this, so at least some useful work gets
490 -- done before the upsweep is abandoned.
491 --hPutStrLn stderr "after tsort:\n"
492 --hPutStrLn stderr (showSDoc (vcat (map ppr mg2)))
494 -- Now do the upsweep, calling compile for each module in
495 -- turn. Final result is version 3 of everything.
497 -- Topologically sort the module graph, this time including hi-boot
498 -- nodes, and possibly just including the portion of the graph
499 -- reachable from the module specified in the 2nd argument to load.
500 -- This graph should be cycle-free.
501 -- If we're restricting the upsweep to a portion of the graph, we
502 -- also want to retain everything that is still stable.
503 let full_mg :: [SCC ModSummary]
504 full_mg = topSortModuleGraph False mod_graph Nothing
506 maybe_top_mod = case how_much of
508 LoadDependenciesOf m -> Just m
511 partial_mg0 :: [SCC ModSummary]
512 partial_mg0 = topSortModuleGraph False mod_graph maybe_top_mod
514 -- LoadDependenciesOf m: we want the upsweep to stop just
515 -- short of the specified module (unless the specified module
518 | LoadDependenciesOf mod <- how_much
519 = ASSERT( case last partial_mg0 of
520 AcyclicSCC ms -> ms_mod ms == mod; _ -> False )
521 List.init partial_mg0
527 | AcyclicSCC ms <- full_mg,
528 ms_mod ms `elem` stable_obj++stable_bco,
529 ms_mod ms `notElem` [ ms_mod ms' |
530 AcyclicSCC ms' <- partial_mg ] ]
532 mg = stable_mg ++ partial_mg
534 -- clean up between compilations
535 let cleanup = cleanTempFilesExcept dflags
536 (ppFilesFromSummaries (flattenSCCs mg2_with_srcimps))
538 (upsweep_ok, hsc_env1, modsUpswept)
539 <- upsweep (hsc_env { hsc_HPT = emptyHomePackageTable })
540 pruned_hpt stable_mods cleanup msg_act mg
542 -- Make modsDone be the summaries for each home module now
543 -- available; this should equal the domain of hpt3.
544 -- Get in in a roughly top .. bottom order (hence reverse).
546 let modsDone = reverse modsUpswept
548 -- Try and do linking in some form, depending on whether the
549 -- upsweep was completely or only partially successful.
551 if succeeded upsweep_ok
554 -- Easy; just relink it all.
555 do debugTraceMsg dflags 2 "Upsweep completely successful."
557 -- Clean up after ourselves
558 cleanTempFilesExcept dflags (ppFilesFromSummaries modsDone)
560 -- Issue a warning for the confusing case where the user
561 -- said '-o foo' but we're not going to do any linking.
562 -- We attempt linking if either (a) one of the modules is
563 -- called Main, or (b) the user said -no-hs-main, indicating
564 -- that main() is going to come from somewhere else.
566 let ofile = outputFile dflags
567 let no_hs_main = dopt Opt_NoHsMain dflags
568 let mb_main_mod = mainModIs dflags
570 main_mod = mb_main_mod `orElse` "Main"
572 = any ((==main_mod).moduleUserString.ms_mod)
574 do_linking = a_root_is_Main || no_hs_main
576 when (ghci_mode == BatchCompile && isJust ofile && not do_linking) $
577 debugTraceMsg dflags 1 ("Warning: output was redirected with -o, " ++
578 "but no output will be generated\n" ++
579 "because there is no " ++ main_mod ++ " module.")
581 -- link everything together
582 linkresult <- link ghci_mode dflags do_linking (hsc_HPT hsc_env1)
584 loadFinish Succeeded linkresult ref hsc_env1
587 -- Tricky. We need to back out the effects of compiling any
588 -- half-done cycles, both so as to clean up the top level envs
589 -- and to avoid telling the interactive linker to link them.
590 do debugTraceMsg dflags 2 "Upsweep partially successful."
593 = map ms_mod modsDone
594 let mods_to_zap_names
595 = findPartiallyCompletedCycles modsDone_names
598 = filter ((`notElem` mods_to_zap_names).ms_mod)
601 let hpt4 = retainInTopLevelEnvs (map ms_mod mods_to_keep)
604 -- Clean up after ourselves
605 cleanTempFilesExcept dflags (ppFilesFromSummaries mods_to_keep)
607 -- there should be no Nothings where linkables should be, now
608 ASSERT(all (isJust.hm_linkable)
609 (moduleEnvElts (hsc_HPT hsc_env))) do
611 -- Link everything together
612 linkresult <- link ghci_mode dflags False hpt4
614 let hsc_env4 = hsc_env1{ hsc_HPT = hpt4 }
615 loadFinish Failed linkresult ref hsc_env4
617 -- Finish up after a load.
619 -- If the link failed, unload everything and return.
620 loadFinish all_ok Failed ref hsc_env
621 = do unload hsc_env []
622 writeIORef ref $! discardProg hsc_env
625 -- Empty the interactive context and set the module context to the topmost
626 -- newly loaded module, or the Prelude if none were loaded.
627 loadFinish all_ok Succeeded ref hsc_env
628 = do writeIORef ref $! hsc_env{ hsc_IC = emptyInteractiveContext }
632 -- Forget the current program, but retain the persistent info in HscEnv
633 discardProg :: HscEnv -> HscEnv
635 = hsc_env { hsc_mod_graph = emptyMG,
636 hsc_IC = emptyInteractiveContext,
637 hsc_HPT = emptyHomePackageTable }
639 -- used to fish out the preprocess output files for the purposes of
640 -- cleaning up. The preprocessed file *might* be the same as the
641 -- source file, but that doesn't do any harm.
642 ppFilesFromSummaries summaries = [ fn | Just fn <- map ms_hspp_file summaries ]
644 -- -----------------------------------------------------------------------------
648 CheckedModule { parsedSource :: ParsedSource,
649 renamedSource :: Maybe RenamedSource,
650 typecheckedSource :: Maybe TypecheckedSource,
651 checkedModuleInfo :: Maybe ModuleInfo
654 type ParsedSource = Located (HsModule RdrName)
655 type RenamedSource = HsGroup Name
656 type TypecheckedSource = LHsBinds Id
658 -- | This is the way to get access to parsed and typechecked source code
659 -- for a module. 'checkModule' loads all the dependencies of the specified
660 -- module in the Session, and then attempts to typecheck the module. If
661 -- successful, it returns the abstract syntax for the module.
662 checkModule :: Session -> Module -> (Messages -> IO ())
663 -> IO (Maybe CheckedModule)
664 checkModule session@(Session ref) mod msg_act = do
665 -- load up the dependencies first
666 r <- loadMsgs session (LoadDependenciesOf mod) msg_act
667 if (failed r) then return Nothing else do
669 -- now parse & typecheck the module
670 hsc_env <- readIORef ref
671 let mg = hsc_mod_graph hsc_env
672 case [ ms | ms <- mg, ms_mod ms == mod ] of
675 -- Add in the OPTIONS from the source file This is nasty:
676 -- we've done this once already, in the compilation manager
677 -- It might be better to cache the flags in the
678 -- ml_hspp_file field, say
679 let dflags0 = hsc_dflags hsc_env
680 hspp_buf = expectJust "GHC.checkModule" (ms_hspp_buf ms)
681 opts = getOptionsFromStringBuffer hspp_buf
682 (dflags1,leftovers) <- parseDynamicFlags dflags0 (map snd opts)
683 if (not (null leftovers))
684 then do let filename = fromJust (ml_hs_file (ms_location ms))
685 msg_act (optionsErrorMsgs leftovers opts filename)
689 r <- hscFileCheck hsc_env{hsc_dflags=dflags1} msg_act ms
693 HscChecked parsed renamed Nothing ->
694 return (Just (CheckedModule {
695 parsedSource = parsed,
696 renamedSource = renamed,
697 typecheckedSource = Nothing,
698 checkedModuleInfo = Nothing }))
699 HscChecked parsed renamed
700 (Just (tc_binds, rdr_env, details)) -> do
701 let minf = ModuleInfo {
702 minf_type_env = md_types details,
703 minf_exports = md_exports details,
704 minf_rdr_env = Just rdr_env
706 return (Just (CheckedModule {
707 parsedSource = parsed,
708 renamedSource = renamed,
709 typecheckedSource = Just tc_binds,
710 checkedModuleInfo = Just minf }))
712 -- ---------------------------------------------------------------------------
715 unload :: HscEnv -> [Linkable] -> IO ()
716 unload hsc_env stable_linkables -- Unload everthing *except* 'stable_linkables'
717 = case ghcMode (hsc_dflags hsc_env) of
718 BatchCompile -> return ()
719 JustTypecheck -> return ()
721 Interactive -> Linker.unload (hsc_dflags hsc_env) stable_linkables
723 Interactive -> panic "unload: no interpreter"
725 other -> panic "unload: strange mode"
727 -- -----------------------------------------------------------------------------
731 Stability tells us which modules definitely do not need to be recompiled.
732 There are two main reasons for having stability:
734 - avoid doing a complete upsweep of the module graph in GHCi when
735 modules near the bottom of the tree have not changed.
737 - to tell GHCi when it can load object code: we can only load object code
738 for a module when we also load object code fo all of the imports of the
739 module. So we need to know that we will definitely not be recompiling
740 any of these modules, and we can use the object code.
742 NB. stability is of no importance to BatchCompile at all, only Interactive.
743 (ToDo: what about JustTypecheck?)
745 The stability check is as follows. Both stableObject and
746 stableBCO are used during the upsweep phase later.
749 stable m = stableObject m || stableBCO m
752 all stableObject (imports m)
753 && old linkable does not exist, or is == on-disk .o
754 && date(on-disk .o) > date(.hs)
757 all stable (imports m)
758 && date(BCO) > date(.hs)
761 These properties embody the following ideas:
763 - if a module is stable:
764 - if it has been compiled in a previous pass (present in HPT)
765 then it does not need to be compiled or re-linked.
766 - if it has not been compiled in a previous pass,
767 then we only need to read its .hi file from disk and
768 link it to produce a ModDetails.
770 - if a modules is not stable, we will definitely be at least
771 re-linking, and possibly re-compiling it during the upsweep.
772 All non-stable modules can (and should) therefore be unlinked
775 - Note that objects are only considered stable if they only depend
776 on other objects. We can't link object code against byte code.
780 :: HomePackageTable -- HPT from last compilation
781 -> [SCC ModSummary] -- current module graph (cyclic)
782 -> [Module] -- all home modules
783 -> ([Module], -- stableObject
784 [Module]) -- stableBCO
786 checkStability hpt sccs all_home_mods = foldl checkSCC ([],[]) sccs
788 checkSCC (stable_obj, stable_bco) scc0
789 | stableObjects = (scc_mods ++ stable_obj, stable_bco)
790 | stableBCOs = (stable_obj, scc_mods ++ stable_bco)
791 | otherwise = (stable_obj, stable_bco)
793 scc = flattenSCC scc0
794 scc_mods = map ms_mod scc
795 home_module m = m `elem` all_home_mods && m `notElem` scc_mods
797 scc_allimps = nub (filter home_module (concatMap ms_allimps scc))
798 -- all imports outside the current SCC, but in the home pkg
800 stable_obj_imps = map (`elem` stable_obj) scc_allimps
801 stable_bco_imps = map (`elem` stable_bco) scc_allimps
808 and (zipWith (||) stable_obj_imps stable_bco_imps)
812 | Just t <- ms_obj_date ms = t >= ms_hs_date ms
816 same_as_prev t = case lookupModuleEnv hpt (ms_mod ms) of
818 Just hmi | Just l <- hm_linkable hmi
819 -> isObjectLinkable l && t == linkableTime l
820 -- why '>=' rather than '>' above? If the filesystem stores
821 -- times to the nearset second, we may occasionally find that
822 -- the object & source have the same modification time,
823 -- especially if the source was automatically generated
824 -- and compiled. Using >= is slightly unsafe, but it matches
828 = case lookupModuleEnv hpt (ms_mod ms) of
830 Just hmi | Just l <- hm_linkable hmi ->
831 not (isObjectLinkable l) &&
832 linkableTime l >= ms_hs_date ms
834 ms_allimps :: ModSummary -> [Module]
835 ms_allimps ms = ms_srcimps ms ++ ms_imps ms
837 -- -----------------------------------------------------------------------------
838 -- Prune the HomePackageTable
840 -- Before doing an upsweep, we can throw away:
842 -- - For non-stable modules:
843 -- - all ModDetails, all linked code
844 -- - all unlinked code that is out of date with respect to
847 -- This is VERY IMPORTANT otherwise we'll end up requiring 2x the
848 -- space at the end of the upsweep, because the topmost ModDetails of the
849 -- old HPT holds on to the entire type environment from the previous
852 pruneHomePackageTable
855 -> ([Module],[Module])
858 pruneHomePackageTable hpt summ (stable_obj, stable_bco)
859 = mapModuleEnv prune hpt
861 | is_stable modl = hmi'
862 | otherwise = hmi'{ hm_details = emptyModDetails }
864 modl = mi_module (hm_iface hmi)
865 hmi' | Just l <- hm_linkable hmi, linkableTime l < ms_hs_date ms
866 = hmi{ hm_linkable = Nothing }
869 where ms = expectJust "prune" (lookupModuleEnv ms_map modl)
871 ms_map = mkModuleEnv [(ms_mod ms, ms) | ms <- summ]
873 is_stable m = m `elem` stable_obj || m `elem` stable_bco
875 -- -----------------------------------------------------------------------------
877 -- Return (names of) all those in modsDone who are part of a cycle
878 -- as defined by theGraph.
879 findPartiallyCompletedCycles :: [Module] -> [SCC ModSummary] -> [Module]
880 findPartiallyCompletedCycles modsDone theGraph
884 chew ((AcyclicSCC v):rest) = chew rest -- acyclic? not interesting.
885 chew ((CyclicSCC vs):rest)
886 = let names_in_this_cycle = nub (map ms_mod vs)
888 = nub ([done | done <- modsDone,
889 done `elem` names_in_this_cycle])
890 chewed_rest = chew rest
892 if notNull mods_in_this_cycle
893 && length mods_in_this_cycle < length names_in_this_cycle
894 then mods_in_this_cycle ++ chewed_rest
897 -- -----------------------------------------------------------------------------
900 -- This is where we compile each module in the module graph, in a pass
901 -- from the bottom to the top of the graph.
903 -- There better had not be any cyclic groups here -- we check for them.
906 :: HscEnv -- Includes initially-empty HPT
907 -> HomePackageTable -- HPT from last time round (pruned)
908 -> ([Module],[Module]) -- stable modules (see checkStability)
909 -> IO () -- How to clean up unwanted tmp files
910 -> (Messages -> IO ()) -- Compiler error message callback
911 -> [SCC ModSummary] -- Mods to do (the worklist)
913 HscEnv, -- With an updated HPT
914 [ModSummary]) -- Mods which succeeded
916 upsweep hsc_env old_hpt stable_mods cleanup msg_act mods
917 = upsweep' hsc_env old_hpt stable_mods cleanup msg_act mods 1 (length mods)
919 upsweep' hsc_env old_hpt stable_mods cleanup msg_act
921 = return (Succeeded, hsc_env, [])
923 upsweep' hsc_env old_hpt stable_mods cleanup msg_act
925 = do putMsg (showSDoc (cyclicModuleErr ms))
926 return (Failed, hsc_env, [])
928 upsweep' hsc_env old_hpt stable_mods cleanup msg_act
929 (AcyclicSCC mod:mods) mod_index nmods
930 = do -- putStrLn ("UPSWEEP_MOD: hpt = " ++
931 -- show (map (moduleUserString.moduleName.mi_module.hm_iface)
932 -- (moduleEnvElts (hsc_HPT hsc_env)))
934 mb_mod_info <- upsweep_mod hsc_env old_hpt stable_mods msg_act mod
937 cleanup -- Remove unwanted tmp files between compilations
940 Nothing -> return (Failed, hsc_env, [])
942 { let this_mod = ms_mod mod
944 -- Add new info to hsc_env
945 hpt1 = extendModuleEnv (hsc_HPT hsc_env)
947 hsc_env1 = hsc_env { hsc_HPT = hpt1 }
949 -- Space-saving: delete the old HPT entry
950 -- for mod BUT if mod is a hs-boot
951 -- node, don't delete it. For the
952 -- interface, the HPT entry is probaby for the
953 -- main Haskell source file. Deleting it
954 -- would force .. (what?? --SDM)
955 old_hpt1 | isBootSummary mod = old_hpt
956 | otherwise = delModuleEnv old_hpt this_mod
958 ; (restOK, hsc_env2, modOKs)
959 <- upsweep' hsc_env1 old_hpt1 stable_mods cleanup
960 msg_act mods (mod_index+1) nmods
961 ; return (restOK, hsc_env2, mod:modOKs)
965 -- Compile a single module. Always produce a Linkable for it if
966 -- successful. If no compilation happened, return the old Linkable.
967 upsweep_mod :: HscEnv
969 -> ([Module],[Module])
970 -> (Messages -> IO ())
972 -> Int -- index of module
973 -> Int -- total number of modules
974 -> IO (Maybe HomeModInfo) -- Nothing => Failed
976 upsweep_mod hsc_env old_hpt (stable_obj, stable_bco) msg_act summary mod_index nmods
979 this_mod = ms_mod summary
980 mb_obj_date = ms_obj_date summary
981 obj_fn = ml_obj_file (ms_location summary)
982 hs_date = ms_hs_date summary
984 compile_it :: Maybe Linkable -> IO (Maybe HomeModInfo)
985 compile_it = upsweep_compile hsc_env old_hpt this_mod
986 msg_act summary mod_index nmods
988 case ghcMode (hsc_dflags hsc_env) of
991 -- Batch-compilating is easy: just check whether we have
992 -- an up-to-date object file. If we do, then the compiler
993 -- needs to do a recompilation check.
994 _ | Just obj_date <- mb_obj_date, obj_date >= hs_date -> do
996 findObjectLinkable this_mod obj_fn obj_date
997 compile_it (Just linkable)
1004 _ | is_stable_obj, isJust old_hmi ->
1006 -- object is stable, and we have an entry in the
1007 -- old HPT: nothing to do
1009 | is_stable_obj, isNothing old_hmi -> do
1011 findObjectLinkable this_mod obj_fn
1012 (expectJust "upseep1" mb_obj_date)
1013 compile_it (Just linkable)
1014 -- object is stable, but we need to load the interface
1015 -- off disk to make a HMI.
1018 ASSERT(isJust old_hmi) -- must be in the old_hpt
1020 -- BCO is stable: nothing to do
1022 | Just hmi <- old_hmi,
1023 Just l <- hm_linkable hmi, not (isObjectLinkable l),
1024 linkableTime l >= ms_hs_date summary ->
1026 -- we have an old BCO that is up to date with respect
1027 -- to the source: do a recompilation check as normal.
1031 -- no existing code at all: we must recompile.
1033 is_stable_obj = this_mod `elem` stable_obj
1034 is_stable_bco = this_mod `elem` stable_bco
1036 old_hmi = lookupModuleEnv old_hpt this_mod
1038 -- Run hsc to compile a module
1039 upsweep_compile hsc_env old_hpt this_mod msg_act summary
1041 mb_old_linkable = do
1043 -- The old interface is ok if it's in the old HPT
1044 -- a) we're compiling a source file, and the old HPT
1045 -- entry is for a source file
1046 -- b) we're compiling a hs-boot file
1047 -- Case (b) allows an hs-boot file to get the interface of its
1048 -- real source file on the second iteration of the compilation
1049 -- manager, but that does no harm. Otherwise the hs-boot file
1050 -- will always be recompiled
1053 = case lookupModuleEnv old_hpt this_mod of
1055 Just hm_info | isBootSummary summary -> Just iface
1056 | not (mi_boot iface) -> Just iface
1057 | otherwise -> Nothing
1059 iface = hm_iface hm_info
1061 compresult <- compile hsc_env msg_act summary mb_old_linkable mb_old_iface
1065 -- Compilation failed. Compile may still have updated the PCS, tho.
1066 CompErrs -> return Nothing
1068 -- Compilation "succeeded", and may or may not have returned a new
1069 -- linkable (depending on whether compilation was actually performed
1071 CompOK new_details new_iface new_linkable
1072 -> do let new_info = HomeModInfo { hm_iface = new_iface,
1073 hm_details = new_details,
1074 hm_linkable = new_linkable }
1075 return (Just new_info)
1078 -- Filter modules in the HPT
1079 retainInTopLevelEnvs :: [Module] -> HomePackageTable -> HomePackageTable
1080 retainInTopLevelEnvs keep_these hpt
1081 = mkModuleEnv [ (mod, expectJust "retain" mb_mod_info)
1083 , let mb_mod_info = lookupModuleEnv hpt mod
1084 , isJust mb_mod_info ]
1086 -- ---------------------------------------------------------------------------
1087 -- Topological sort of the module graph
1090 :: Bool -- Drop hi-boot nodes? (see below)
1094 -- Calculate SCCs of the module graph, possibly dropping the hi-boot nodes
1095 -- The resulting list of strongly-connected-components is in topologically
1096 -- sorted order, starting with the module(s) at the bottom of the
1097 -- dependency graph (ie compile them first) and ending with the ones at
1100 -- Drop hi-boot nodes (first boolean arg)?
1102 -- False: treat the hi-boot summaries as nodes of the graph,
1103 -- so the graph must be acyclic
1105 -- True: eliminate the hi-boot nodes, and instead pretend
1106 -- the a source-import of Foo is an import of Foo
1107 -- The resulting graph has no hi-boot nodes, but can by cyclic
1109 topSortModuleGraph drop_hs_boot_nodes summaries Nothing
1110 = stronglyConnComp (fst (moduleGraphNodes drop_hs_boot_nodes summaries))
1111 topSortModuleGraph drop_hs_boot_nodes summaries (Just mod)
1112 = stronglyConnComp (map vertex_fn (reachable graph root))
1114 -- restrict the graph to just those modules reachable from
1115 -- the specified module. We do this by building a graph with
1116 -- the full set of nodes, and determining the reachable set from
1117 -- the specified node.
1118 (nodes, lookup_key) = moduleGraphNodes drop_hs_boot_nodes summaries
1119 (graph, vertex_fn, key_fn) = graphFromEdges' nodes
1121 | Just key <- lookup_key HsSrcFile mod, Just v <- key_fn key = v
1122 | otherwise = throwDyn (ProgramError "module does not exist")
1124 moduleGraphNodes :: Bool -> [ModSummary]
1125 -> ([(ModSummary, Int, [Int])], HscSource -> Module -> Maybe Int)
1126 moduleGraphNodes drop_hs_boot_nodes summaries = (nodes, lookup_key)
1128 -- Drop hs-boot nodes by using HsSrcFile as the key
1129 hs_boot_key | drop_hs_boot_nodes = HsSrcFile
1130 | otherwise = HsBootFile
1132 -- We use integers as the keys for the SCC algorithm
1133 nodes :: [(ModSummary, Int, [Int])]
1134 nodes = [(s, expectJust "topSort" (lookup_key (ms_hsc_src s) (ms_mod s)),
1135 out_edge_keys hs_boot_key (ms_srcimps s) ++
1136 out_edge_keys HsSrcFile (ms_imps s) )
1138 , not (isBootSummary s && drop_hs_boot_nodes) ]
1139 -- Drop the hi-boot ones if told to do so
1141 key_map :: NodeMap Int
1142 key_map = listToFM ([(ms_mod s, ms_hsc_src s) | s <- summaries]
1145 lookup_key :: HscSource -> Module -> Maybe Int
1146 lookup_key hs_src mod = lookupFM key_map (mod, hs_src)
1148 out_edge_keys :: HscSource -> [Module] -> [Int]
1149 out_edge_keys hi_boot ms = mapCatMaybes (lookup_key hi_boot) ms
1150 -- If we want keep_hi_boot_nodes, then we do lookup_key with
1151 -- the IsBootInterface parameter True; else False
1154 type NodeKey = (Module, HscSource) -- The nodes of the graph are
1155 type NodeMap a = FiniteMap NodeKey a -- keyed by (mod, src_file_type) pairs
1157 msKey :: ModSummary -> NodeKey
1158 msKey (ModSummary { ms_mod = mod, ms_hsc_src = boot }) = (mod,boot)
1160 emptyNodeMap :: NodeMap a
1161 emptyNodeMap = emptyFM
1163 mkNodeMap :: [ModSummary] -> NodeMap ModSummary
1164 mkNodeMap summaries = listToFM [ (msKey s, s) | s <- summaries]
1166 nodeMapElts :: NodeMap a -> [a]
1167 nodeMapElts = eltsFM
1169 -- -----------------------------------------------------------------
1170 -- The unlinked image
1172 -- The compilation manager keeps a list of compiled, but as-yet unlinked
1173 -- binaries (byte code or object code). Even when it links bytecode
1174 -- it keeps the unlinked version so it can re-link it later without
1177 type UnlinkedImage = [Linkable] -- the unlinked images (should be a set, really)
1179 findModuleLinkable_maybe :: [Linkable] -> Module -> Maybe Linkable
1180 findModuleLinkable_maybe lis mod
1181 = case [LM time nm us | LM time nm us <- lis, nm == mod] of
1184 many -> pprPanic "findModuleLinkable" (ppr mod)
1186 delModuleLinkable :: [Linkable] -> Module -> [Linkable]
1187 delModuleLinkable ls mod = [ l | l@(LM _ nm _) <- ls, nm /= mod ]
1189 -----------------------------------------------------------------------------
1190 -- Downsweep (dependency analysis)
1192 -- Chase downwards from the specified root set, returning summaries
1193 -- for all home modules encountered. Only follow source-import
1196 -- We pass in the previous collection of summaries, which is used as a
1197 -- cache to avoid recalculating a module summary if the source is
1200 -- The returned list of [ModSummary] nodes has one node for each home-package
1201 -- module, plus one for any hs-boot files. The imports of these nodes
1202 -- are all there, including the imports of non-home-package modules.
1205 -> [ModSummary] -- Old summaries
1206 -> [Module] -- Ignore dependencies on these; treat them as
1207 -- if they were package modules
1209 downsweep hsc_env old_summaries excl_mods
1210 = do rootSummaries <- mapM getRootSummary roots
1211 checkDuplicates rootSummaries
1212 loop (concatMap msDeps rootSummaries)
1213 (mkNodeMap rootSummaries)
1215 roots = hsc_targets hsc_env
1217 old_summary_map :: NodeMap ModSummary
1218 old_summary_map = mkNodeMap old_summaries
1220 getRootSummary :: Target -> IO ModSummary
1221 getRootSummary (Target (TargetFile file mb_phase) maybe_buf)
1222 = do exists <- doesFileExist file
1224 then summariseFile hsc_env old_summaries file mb_phase maybe_buf
1226 throwDyn (CmdLineError ("can't find file: " ++ file))
1227 getRootSummary (Target (TargetModule modl) maybe_buf)
1228 = do maybe_summary <- summariseModule hsc_env old_summary_map Nothing False
1229 modl maybe_buf excl_mods
1230 case maybe_summary of
1231 Nothing -> packageModErr modl
1234 -- In a root module, the filename is allowed to diverge from the module
1235 -- name, so we have to check that there aren't multiple root files
1236 -- defining the same module (otherwise the duplicates will be silently
1237 -- ignored, leading to confusing behaviour).
1238 checkDuplicates :: [ModSummary] -> IO ()
1239 checkDuplicates summaries = mapM_ check summaries
1244 many -> multiRootsErr modl many
1245 where modl = ms_mod summ
1247 [ expectJust "checkDup" (ml_hs_file (ms_location summ'))
1248 | summ' <- summaries, ms_mod summ' == modl ]
1250 loop :: [(FilePath,Module,IsBootInterface)]
1251 -- Work list: process these modules
1252 -> NodeMap ModSummary
1255 -- The result includes the worklist, except
1256 -- for those mentioned in the visited set
1257 loop [] done = return (nodeMapElts done)
1258 loop ((cur_path, wanted_mod, is_boot) : ss) done
1259 | key `elemFM` done = loop ss done
1260 | otherwise = do { mb_s <- summariseModule hsc_env old_summary_map
1261 (Just cur_path) is_boot
1262 wanted_mod Nothing excl_mods
1264 Nothing -> loop ss done
1265 Just s -> loop (msDeps s ++ ss)
1266 (addToFM done key s) }
1268 key = (wanted_mod, if is_boot then HsBootFile else HsSrcFile)
1270 msDeps :: ModSummary -> [(FilePath, -- Importing module
1271 Module, -- Imported module
1272 IsBootInterface)] -- {-# SOURCE #-} import or not
1273 -- (msDeps s) returns the dependencies of the ModSummary s.
1274 -- A wrinkle is that for a {-# SOURCE #-} import we return
1275 -- *both* the hs-boot file
1276 -- *and* the source file
1277 -- as "dependencies". That ensures that the list of all relevant
1278 -- modules always contains B.hs if it contains B.hs-boot.
1279 -- Remember, this pass isn't doing the topological sort. It's
1280 -- just gathering the list of all relevant ModSummaries
1281 msDeps s = concat [ [(f, m, True), (f,m,False)] | m <- ms_srcimps s]
1282 ++ [(f,m,False) | m <- ms_imps s]
1284 f = msHsFilePath s -- Keep the importing module for error reporting
1287 -----------------------------------------------------------------------------
1288 -- Summarising modules
1290 -- We have two types of summarisation:
1292 -- * Summarise a file. This is used for the root module(s) passed to
1293 -- cmLoadModules. The file is read, and used to determine the root
1294 -- module name. The module name may differ from the filename.
1296 -- * Summarise a module. We are given a module name, and must provide
1297 -- a summary. The finder is used to locate the file in which the module
1302 -> [ModSummary] -- old summaries
1303 -> FilePath -- source file name
1304 -> Maybe Phase -- start phase
1305 -> Maybe (StringBuffer,ClockTime)
1308 summariseFile hsc_env old_summaries file mb_phase maybe_buf
1309 -- we can use a cached summary if one is available and the
1310 -- source file hasn't changed, But we have to look up the summary
1311 -- by source file, rather than module name as we do in summarise.
1312 | Just old_summary <- findSummaryBySourceFile old_summaries file
1314 let location = ms_location old_summary
1316 -- return the cached summary if the source didn't change
1317 src_timestamp <- case maybe_buf of
1318 Just (_,t) -> return t
1319 Nothing -> getModificationTime file
1321 if ms_hs_date old_summary == src_timestamp
1322 then do -- update the object-file timestamp
1323 obj_timestamp <- getObjTimestamp location False
1324 return old_summary{ ms_obj_date = obj_timestamp }
1332 let dflags = hsc_dflags hsc_env
1334 (dflags', hspp_fn, buf)
1335 <- preprocessFile dflags file mb_phase maybe_buf
1337 (srcimps,the_imps,mod) <- getImports dflags' buf hspp_fn
1339 -- Make a ModLocation for this file
1340 location <- mkHomeModLocation dflags mod file
1342 -- Tell the Finder cache where it is, so that subsequent calls
1343 -- to findModule will find it, even if it's not on any search path
1344 addHomeModuleToFinder hsc_env mod location
1346 src_timestamp <- case maybe_buf of
1347 Just (_,t) -> return t
1348 Nothing -> getModificationTime file
1350 obj_timestamp <- modificationTimeIfExists (ml_obj_file location)
1352 return (ModSummary { ms_mod = mod, ms_hsc_src = HsSrcFile,
1353 ms_location = location,
1354 ms_hspp_file = Just hspp_fn,
1355 ms_hspp_buf = Just buf,
1356 ms_srcimps = srcimps, ms_imps = the_imps,
1357 ms_hs_date = src_timestamp,
1358 ms_obj_date = obj_timestamp })
1360 findSummaryBySourceFile :: [ModSummary] -> FilePath -> Maybe ModSummary
1361 findSummaryBySourceFile summaries file
1362 = case [ ms | ms <- summaries, HsSrcFile <- [ms_hsc_src ms],
1363 fromJust (ml_hs_file (ms_location ms)) == file ] of
1367 -- Summarise a module, and pick up source and timestamp.
1370 -> NodeMap ModSummary -- Map of old summaries
1371 -> Maybe FilePath -- Importing module (for error messages)
1372 -> IsBootInterface -- True <=> a {-# SOURCE #-} import
1373 -> Module -- Imported module to be summarised
1374 -> Maybe (StringBuffer, ClockTime)
1375 -> [Module] -- Modules to exclude
1376 -> IO (Maybe ModSummary) -- Its new summary
1378 summariseModule hsc_env old_summary_map cur_mod is_boot wanted_mod maybe_buf excl_mods
1379 | wanted_mod `elem` excl_mods
1382 | Just old_summary <- lookupFM old_summary_map (wanted_mod, hsc_src)
1383 = do -- Find its new timestamp; all the
1384 -- ModSummaries in the old map have valid ml_hs_files
1385 let location = ms_location old_summary
1386 src_fn = expectJust "summariseModule" (ml_hs_file location)
1388 -- return the cached summary if the source didn't change
1389 src_timestamp <- case maybe_buf of
1390 Just (_,t) -> return t
1391 Nothing -> getModificationTime src_fn
1393 if ms_hs_date old_summary == src_timestamp
1394 then do -- update the object-file timestamp
1395 obj_timestamp <- getObjTimestamp location is_boot
1396 return (Just old_summary{ ms_obj_date = obj_timestamp })
1398 -- source changed: re-summarise
1399 new_summary location src_fn maybe_buf src_timestamp
1402 = do found <- findModule hsc_env wanted_mod True {-explicit-}
1405 | not (isHomePackage pkg) -> return Nothing
1406 -- Drop external-pkg
1407 | isJust (ml_hs_file location) -> just_found location
1409 err -> noModError dflags cur_mod wanted_mod err
1412 dflags = hsc_dflags hsc_env
1414 hsc_src = if is_boot then HsBootFile else HsSrcFile
1416 just_found location = do
1417 -- Adjust location to point to the hs-boot source file,
1418 -- hi file, object file, when is_boot says so
1419 let location' | is_boot = addBootSuffixLocn location
1420 | otherwise = location
1421 src_fn = expectJust "summarise2" (ml_hs_file location')
1423 -- Check that it exists
1424 -- It might have been deleted since the Finder last found it
1425 maybe_t <- modificationTimeIfExists src_fn
1427 Nothing -> noHsFileErr cur_mod src_fn
1428 Just t -> new_summary location' src_fn Nothing t
1431 new_summary location src_fn maybe_bug src_timestamp
1433 -- Preprocess the source file and get its imports
1434 -- The dflags' contains the OPTIONS pragmas
1435 (dflags', hspp_fn, buf) <- preprocessFile dflags src_fn Nothing maybe_buf
1436 (srcimps, the_imps, mod_name) <- getImports dflags' buf hspp_fn
1438 when (mod_name /= wanted_mod) $
1439 throwDyn (ProgramError
1440 (showSDoc (text src_fn
1441 <> text ": file name does not match module name"
1442 <+> quotes (ppr mod_name))))
1444 -- Find the object timestamp, and return the summary
1445 obj_timestamp <- getObjTimestamp location is_boot
1447 return (Just ( ModSummary { ms_mod = wanted_mod,
1448 ms_hsc_src = hsc_src,
1449 ms_location = location,
1450 ms_hspp_file = Just hspp_fn,
1451 ms_hspp_buf = Just buf,
1452 ms_srcimps = srcimps,
1454 ms_hs_date = src_timestamp,
1455 ms_obj_date = obj_timestamp }))
1458 getObjTimestamp location is_boot
1459 = if is_boot then return Nothing
1460 else modificationTimeIfExists (ml_obj_file location)
1463 preprocessFile :: DynFlags -> FilePath -> Maybe Phase -> Maybe (StringBuffer,ClockTime)
1464 -> IO (DynFlags, FilePath, StringBuffer)
1465 preprocessFile dflags src_fn mb_phase Nothing
1467 (dflags', hspp_fn) <- preprocess dflags (src_fn, mb_phase)
1468 buf <- hGetStringBuffer hspp_fn
1469 return (dflags', hspp_fn, buf)
1471 preprocessFile dflags src_fn mb_phase (Just (buf, time))
1473 -- case we bypass the preprocessing stage?
1475 local_opts = getOptionsFromStringBuffer buf
1477 (dflags', errs) <- parseDynamicFlags dflags (map snd local_opts)
1481 | Just (Unlit _) <- mb_phase = True
1482 | Nothing <- mb_phase, Unlit _ <- startPhase src_fn = True
1483 -- note: local_opts is only required if there's no Unlit phase
1484 | dopt Opt_Cpp dflags' = True
1485 | dopt Opt_Pp dflags' = True
1488 when needs_preprocessing $
1489 ghcError (ProgramError "buffer needs preprocesing; interactive check disabled")
1491 return (dflags', src_fn, buf)
1494 -----------------------------------------------------------------------------
1496 -----------------------------------------------------------------------------
1498 noModError :: DynFlags -> Maybe FilePath -> Module -> FindResult -> IO ab
1499 -- ToDo: we don't have a proper line number for this error
1500 noModError dflags cur_mod wanted_mod err
1501 = throwDyn $ ProgramError $ showSDoc $
1502 vcat [cantFindError dflags wanted_mod err,
1503 nest 2 (parens (pp_where cur_mod))]
1505 noHsFileErr cur_mod path
1506 = throwDyn $ CmdLineError $ showSDoc $
1507 vcat [text "Can't find" <+> text path,
1508 nest 2 (parens (pp_where cur_mod))]
1510 pp_where Nothing = text "one of the roots of the dependency analysis"
1511 pp_where (Just p) = text "imported from" <+> text p
1514 = throwDyn (CmdLineError (showSDoc (text "module" <+>
1515 quotes (ppr mod) <+>
1516 text "is a package module")))
1518 multiRootsErr mod files
1519 = throwDyn (ProgramError (showSDoc (
1520 text "module" <+> quotes (ppr mod) <+>
1521 text "is defined in multiple files:" <+>
1522 sep (map text files))))
1524 cyclicModuleErr :: [ModSummary] -> SDoc
1526 = hang (ptext SLIT("Module imports form a cycle for modules:"))
1527 2 (vcat (map show_one ms))
1529 show_one ms = sep [ show_mod (ms_hsc_src ms) (ms_mod ms),
1530 nest 2 $ ptext SLIT("imports:") <+>
1531 (pp_imps HsBootFile (ms_srcimps ms)
1532 $$ pp_imps HsSrcFile (ms_imps ms))]
1533 show_mod hsc_src mod = ppr mod <> text (hscSourceString hsc_src)
1534 pp_imps src mods = fsep (map (show_mod src) mods)
1537 -- | Inform GHC that the working directory has changed. GHC will flush
1538 -- its cache of module locations, since it may no longer be valid.
1539 -- Note: if you change the working directory, you should also unload
1540 -- the current program (set targets to empty, followed by load).
1541 workingDirectoryChanged :: Session -> IO ()
1542 workingDirectoryChanged s = withSession s $ \hsc_env ->
1543 flushFinderCache (hsc_FC hsc_env)
1545 -- -----------------------------------------------------------------------------
1546 -- inspecting the session
1548 -- | Get the module dependency graph.
1549 getModuleGraph :: Session -> IO ModuleGraph -- ToDo: DiGraph ModSummary
1550 getModuleGraph s = withSession s (return . hsc_mod_graph)
1552 isLoaded :: Session -> Module -> IO Bool
1553 isLoaded s m = withSession s $ \hsc_env ->
1554 return $! isJust (lookupModuleEnv (hsc_HPT hsc_env) m)
1556 getBindings :: Session -> IO [TyThing]
1557 getBindings s = withSession s (return . nameEnvElts . ic_type_env . hsc_IC)
1559 getPrintUnqual :: Session -> IO PrintUnqualified
1560 getPrintUnqual s = withSession s (return . icPrintUnqual . hsc_IC)
1562 -- | Container for information about a 'Module'.
1563 data ModuleInfo = ModuleInfo {
1564 minf_type_env :: TypeEnv,
1565 minf_exports :: NameSet,
1566 minf_rdr_env :: Maybe GlobalRdrEnv
1568 -- ToDo: this should really contain the ModIface too
1569 -- We don't want HomeModInfo here, because a ModuleInfo applies
1570 -- to package modules too.
1572 -- | Request information about a loaded 'Module'
1573 getModuleInfo :: Session -> Module -> IO (Maybe ModuleInfo)
1574 getModuleInfo s mdl = withSession s $ \hsc_env -> do
1575 case lookupModuleEnv (hsc_HPT hsc_env) mdl of
1578 mb_names <- getModuleExports hsc_env mdl
1580 Nothing -> return Nothing
1582 eps <- readIORef (hsc_EPS hsc_env)
1585 n_list = nameSetToList names
1586 tys = [ ty | name <- n_list,
1587 Just ty <- [lookupTypeEnv pte name] ]
1589 return (Just (ModuleInfo {
1590 minf_type_env = mkTypeEnv tys,
1591 minf_exports = names,
1592 minf_rdr_env = Just $! nameSetToGlobalRdrEnv names mdl
1595 -- bogusly different for non-GHCI (ToDo)
1599 let details = hm_details hmi in
1600 return (Just (ModuleInfo {
1601 minf_type_env = md_types details,
1602 minf_exports = md_exports details,
1603 minf_rdr_env = mi_globals $! hm_iface hmi
1606 -- ToDo: we should be able to call getModuleInfo on a package module,
1607 -- even one that isn't loaded yet.
1609 -- | The list of top-level entities defined in a module
1610 modInfoTyThings :: ModuleInfo -> [TyThing]
1611 modInfoTyThings minf = typeEnvElts (minf_type_env minf)
1613 modInfoTopLevelScope :: ModuleInfo -> Maybe [Name]
1614 modInfoTopLevelScope minf
1615 = fmap (map gre_name . globalRdrEnvElts) (minf_rdr_env minf)
1617 modInfoExports :: ModuleInfo -> [Name]
1618 modInfoExports minf = nameSetToList $! minf_exports minf
1620 modInfoIsExportedName :: ModuleInfo -> Name -> Bool
1621 modInfoIsExportedName minf name = elemNameSet name (minf_exports minf)
1623 modInfoPrintUnqualified :: ModuleInfo -> Maybe PrintUnqualified
1624 modInfoPrintUnqualified minf = fmap unQualInScope (minf_rdr_env minf)
1626 modInfoLookupName :: Session -> ModuleInfo -> Name -> IO (Maybe TyThing)
1627 modInfoLookupName s minf name = withSession s $ \hsc_env -> do
1628 case lookupTypeEnv (minf_type_env minf) name of
1629 Just tyThing -> return (Just tyThing)
1631 eps <- readIORef (hsc_EPS hsc_env)
1632 return $! lookupType (hsc_HPT hsc_env) (eps_PTE eps) name
1634 isDictonaryId :: Id -> Bool
1636 = case tcSplitSigmaTy (idType id) of { (tvs, theta, tau) -> isDictTy tau }
1638 -- | Looks up a global name: that is, any top-level name in any
1639 -- visible module. Unlike 'lookupName', lookupGlobalName does not use
1640 -- the interactive context, and therefore does not require a preceding
1642 lookupGlobalName :: Session -> Name -> IO (Maybe TyThing)
1643 lookupGlobalName s name = withSession s $ \hsc_env -> do
1644 eps <- readIORef (hsc_EPS hsc_env)
1645 return $! lookupType (hsc_HPT hsc_env) (eps_PTE eps) name
1651 | BinaryCode FilePath
1653 -- ToDo: typechecks abstract syntax or renamed abstract syntax. Issues:
1654 -- - typechecked syntax includes extra dictionary translation and
1655 -- AbsBinds which need to be translated back into something closer to
1656 -- the original source.
1659 -- - Data and Typeable instances for HsSyn.
1662 -- - things that aren't in the output of the renamer:
1663 -- - the export list
1667 -- - things that aren't in the output of the typechecker right now:
1668 -- - the export list
1670 -- - type signatures
1671 -- - type/data/newtype declarations
1672 -- - class declarations
1674 -- - extra things in the typechecker's output:
1675 -- - default methods are turned into top-level decls.
1676 -- - dictionary bindings
1678 -- ToDo: check for small transformations that happen to the syntax in
1679 -- the typechecker (eg. -e ==> negate e, perhaps for fromIntegral)
1681 -- ToDo: maybe use TH syntax instead of IfaceSyn? There's already a way
1682 -- to get from TyCons, Ids etc. to TH syntax (reify).
1684 -- :browse will use either lm_toplev or inspect lm_interface, depending
1685 -- on whether the module is interpreted or not.
1687 -- This is for reconstructing refactored source code
1688 -- Calls the lexer repeatedly.
1689 -- ToDo: add comment tokens to token stream
1690 getTokenStream :: Session -> Module -> IO [Located Token]
1693 -- -----------------------------------------------------------------------------
1694 -- Interactive evaluation
1698 -- | Set the interactive evaluation context.
1700 -- Setting the context doesn't throw away any bindings; the bindings
1701 -- we've built up in the InteractiveContext simply move to the new
1702 -- module. They always shadow anything in scope in the current context.
1703 setContext :: Session
1704 -> [Module] -- entire top level scope of these modules
1705 -> [Module] -- exports only of these modules
1707 setContext (Session ref) toplevs exports = do
1708 hsc_env <- readIORef ref
1709 let old_ic = hsc_IC hsc_env
1710 hpt = hsc_HPT hsc_env
1712 mapM_ (checkModuleExists hsc_env hpt) exports
1713 export_env <- mkExportEnv hsc_env exports
1714 toplev_envs <- mapM (mkTopLevEnv hpt) toplevs
1715 let all_env = foldr plusGlobalRdrEnv export_env toplev_envs
1716 writeIORef ref hsc_env{ hsc_IC = old_ic { ic_toplev_scope = toplevs,
1717 ic_exports = exports,
1718 ic_rn_gbl_env = all_env } }
1720 -- Make a GlobalRdrEnv based on the exports of the modules only.
1721 mkExportEnv :: HscEnv -> [Module] -> IO GlobalRdrEnv
1722 mkExportEnv hsc_env mods = do
1723 mb_name_sets <- mapM (getModuleExports hsc_env) mods
1725 gres = [ nameSetToGlobalRdrEnv name_set mod
1726 | (Just name_set, mod) <- zip mb_name_sets mods ]
1728 return $! foldr plusGlobalRdrEnv emptyGlobalRdrEnv gres
1730 nameSetToGlobalRdrEnv :: NameSet -> Module -> GlobalRdrEnv
1731 nameSetToGlobalRdrEnv names mod =
1732 mkGlobalRdrEnv [ GRE { gre_name = name, gre_prov = vanillaProv mod }
1733 | name <- nameSetToList names ]
1735 vanillaProv :: Module -> Provenance
1736 -- We're building a GlobalRdrEnv as if the user imported
1737 -- all the specified modules into the global interactive module
1738 vanillaProv mod = Imported [ImportSpec { is_mod = mod, is_as = mod,
1739 is_qual = False, is_explicit = False,
1740 is_loc = srcLocSpan interactiveSrcLoc }]
1742 checkModuleExists :: HscEnv -> HomePackageTable -> Module -> IO ()
1743 checkModuleExists hsc_env hpt mod =
1744 case lookupModuleEnv hpt mod of
1745 Just mod_info -> return ()
1746 _not_a_home_module -> do
1747 res <- findPackageModule hsc_env mod True
1749 Found _ _ -> return ()
1750 err -> let msg = cantFindError (hsc_dflags hsc_env) mod err in
1751 throwDyn (CmdLineError (showSDoc msg))
1753 mkTopLevEnv :: HomePackageTable -> Module -> IO GlobalRdrEnv
1754 mkTopLevEnv hpt modl
1755 = case lookupModuleEnv hpt modl of
1757 throwDyn (ProgramError ("mkTopLevEnv: not a home module "
1758 ++ showSDoc (pprModule modl)))
1760 case mi_globals (hm_iface details) of
1762 throwDyn (ProgramError ("mkTopLevEnv: not interpreted "
1763 ++ showSDoc (pprModule modl)))
1764 Just env -> return env
1766 -- | Get the interactive evaluation context, consisting of a pair of the
1767 -- set of modules from which we take the full top-level scope, and the set
1768 -- of modules from which we take just the exports respectively.
1769 getContext :: Session -> IO ([Module],[Module])
1770 getContext s = withSession s (\HscEnv{ hsc_IC=ic } ->
1771 return (ic_toplev_scope ic, ic_exports ic))
1773 -- | Returns 'True' if the specified module is interpreted, and hence has
1774 -- its full top-level scope available.
1775 moduleIsInterpreted :: Session -> Module -> IO Bool
1776 moduleIsInterpreted s modl = withSession s $ \h ->
1777 case lookupModuleEnv (hsc_HPT h) modl of
1778 Just details -> return (isJust (mi_globals (hm_iface details)))
1779 _not_a_home_module -> return False
1781 -- | Looks up an identifier in the current interactive context (for :info)
1782 {-# DEPRECATED getInfo "we should be using parseName/lookupName instead" #-}
1783 getInfo :: Session -> String -> IO [GetInfoResult]
1784 getInfo s id = withSession s $ \hsc_env -> hscGetInfo hsc_env id
1786 -- | Returns all names in scope in the current interactive context
1787 getNamesInScope :: Session -> IO [Name]
1788 getNamesInScope s = withSession s $ \hsc_env -> do
1789 return (map gre_name (globalRdrEnvElts (ic_rn_gbl_env (hsc_IC hsc_env))))
1791 -- | Parses a string as an identifier, and returns the list of 'Name's that
1792 -- the identifier can refer to in the current interactive context.
1793 parseName :: Session -> String -> IO [Name]
1794 parseName s str = withSession s $ \hsc_env -> do
1795 maybe_rdr_name <- hscParseIdentifier (hsc_dflags hsc_env) str
1796 case maybe_rdr_name of
1797 Nothing -> return []
1798 Just (L _ rdr_name) -> do
1799 mb_names <- tcRnLookupRdrName hsc_env rdr_name
1801 Nothing -> return []
1802 Just ns -> return ns
1803 -- ToDo: should return error messages
1805 -- | Returns the 'TyThing' for a 'Name'. The 'Name' may refer to any
1806 -- entity known to GHC, including 'Name's defined using 'runStmt'.
1807 lookupName :: Session -> Name -> IO (Maybe TyThing)
1808 lookupName s name = withSession s $ \hsc_env -> do
1809 case lookupTypeEnv (ic_type_env (hsc_IC hsc_env)) name of
1810 Just tt -> return (Just tt)
1812 eps <- readIORef (hsc_EPS hsc_env)
1813 return $! lookupType (hsc_HPT hsc_env) (eps_PTE eps) name
1815 -- -----------------------------------------------------------------------------
1816 -- Getting the type of an expression
1818 -- | Get the type of an expression
1819 exprType :: Session -> String -> IO (Maybe Type)
1820 exprType s expr = withSession s $ \hsc_env -> do
1821 maybe_stuff <- hscTcExpr hsc_env expr
1823 Nothing -> return Nothing
1824 Just ty -> return (Just tidy_ty)
1826 tidy_ty = tidyType emptyTidyEnv ty
1827 dflags = hsc_dflags hsc_env
1829 -- -----------------------------------------------------------------------------
1830 -- Getting the kind of a type
1832 -- | Get the kind of a type
1833 typeKind :: Session -> String -> IO (Maybe Kind)
1834 typeKind s str = withSession s $ \hsc_env -> do
1835 maybe_stuff <- hscKcType hsc_env str
1837 Nothing -> return Nothing
1838 Just kind -> return (Just kind)
1840 -----------------------------------------------------------------------------
1841 -- cmCompileExpr: compile an expression and deliver an HValue
1843 compileExpr :: Session -> String -> IO (Maybe HValue)
1844 compileExpr s expr = withSession s $ \hsc_env -> do
1845 maybe_stuff <- hscStmt hsc_env ("let __cmCompileExpr = "++expr)
1847 Nothing -> return Nothing
1848 Just (new_ic, names, hval) -> do
1850 hvals <- (unsafeCoerce# hval) :: IO [HValue]
1852 case (names,hvals) of
1853 ([n],[hv]) -> return (Just hv)
1854 _ -> panic "compileExpr"
1856 -- -----------------------------------------------------------------------------
1857 -- running a statement interactively
1860 = RunOk [Name] -- ^ names bound by this evaluation
1861 | RunFailed -- ^ statement failed compilation
1862 | RunException Exception -- ^ statement raised an exception
1864 -- | Run a statement in the current interactive context. Statemenet
1865 -- may bind multple values.
1866 runStmt :: Session -> String -> IO RunResult
1867 runStmt (Session ref) expr
1869 hsc_env <- readIORef ref
1871 -- Turn off -fwarn-unused-bindings when running a statement, to hide
1872 -- warnings about the implicit bindings we introduce.
1873 let dflags' = dopt_unset (hsc_dflags hsc_env) Opt_WarnUnusedBinds
1874 hsc_env' = hsc_env{ hsc_dflags = dflags' }
1876 maybe_stuff <- hscStmt hsc_env' expr
1879 Nothing -> return RunFailed
1880 Just (new_hsc_env, names, hval) -> do
1882 let thing_to_run = unsafeCoerce# hval :: IO [HValue]
1883 either_hvals <- sandboxIO thing_to_run
1885 case either_hvals of
1887 -- on error, keep the *old* interactive context,
1888 -- so that 'it' is not bound to something
1889 -- that doesn't exist.
1890 return (RunException e)
1893 -- Get the newly bound things, and bind them.
1894 -- Don't need to delete any shadowed bindings;
1895 -- the new ones override the old ones.
1896 extendLinkEnv (zip names hvals)
1898 writeIORef ref new_hsc_env
1899 return (RunOk names)
1902 -- We run the statement in a "sandbox" to protect the rest of the
1903 -- system from anything the expression might do. For now, this
1904 -- consists of just wrapping it in an exception handler, but see below
1905 -- for another version.
1907 sandboxIO :: IO a -> IO (Either Exception a)
1908 sandboxIO thing = Exception.try thing
1911 -- This version of sandboxIO runs the expression in a completely new
1912 -- RTS main thread. It is disabled for now because ^C exceptions
1913 -- won't be delivered to the new thread, instead they'll be delivered
1914 -- to the (blocked) GHCi main thread.
1916 -- SLPJ: when re-enabling this, reflect a wrong-stat error as an exception
1918 sandboxIO :: IO a -> IO (Either Int (Either Exception a))
1919 sandboxIO thing = do
1920 st_thing <- newStablePtr (Exception.try thing)
1921 alloca $ \ p_st_result -> do
1922 stat <- rts_evalStableIO st_thing p_st_result
1923 freeStablePtr st_thing
1925 then do st_result <- peek p_st_result
1926 result <- deRefStablePtr st_result
1927 freeStablePtr st_result
1928 return (Right result)
1930 return (Left (fromIntegral stat))
1932 foreign import "rts_evalStableIO" {- safe -}
1933 rts_evalStableIO :: StablePtr (IO a) -> Ptr (StablePtr a) -> IO CInt
1934 -- more informative than the C type!
1937 -- ---------------------------------------------------------------------------
1938 -- cmBrowseModule: get all the TyThings defined in a module
1940 {-# DEPRECATED browseModule "we should be using getModuleInfo instead" #-}
1941 browseModule :: Session -> Module -> Bool -> IO [IfaceDecl]
1942 browseModule s modl exports_only = withSession s $ \hsc_env -> do
1943 mb_decls <- getModuleContents hsc_env modl exports_only
1945 Nothing -> return [] -- An error of some kind
1946 Just ds -> return ds
1949 -----------------------------------------------------------------------------
1950 -- show a module and it's source/object filenames
1952 showModule :: Session -> ModSummary -> IO String
1953 showModule s mod_summary = withSession s $ \hsc_env -> do
1954 case lookupModuleEnv (hsc_HPT hsc_env) (ms_mod mod_summary) of
1955 Nothing -> panic "missing linkable"
1956 Just mod_info -> return (showModMsg obj_linkable mod_summary)
1958 obj_linkable = isObjectLinkable (fromJust (hm_linkable mod_info))