trac #2362 (full import syntax in ghci)
[ghc.git] / compiler / main / GHC.hs
1 -- -----------------------------------------------------------------------------
2 --
3 -- (c) The University of Glasgow, 2005
4 --
5 -- The GHC API
6 --
7 -- -----------------------------------------------------------------------------
8
9 module GHC (
10 -- * Initialisation
11 defaultErrorHandler,
12 defaultCleanupHandler,
13
14 -- * GHC Monad
15 Ghc, GhcT, GhcMonad(..),
16 runGhc, runGhcT, initGhcMonad,
17 gcatch, gbracket, gfinally,
18 clearWarnings, getWarnings, hasWarnings,
19 printExceptionAndWarnings, printWarnings,
20 handleSourceError, defaultCallbacks, GhcApiCallbacks(..),
21 needsTemplateHaskell,
22
23 -- * Flags and settings
24 DynFlags(..), DynFlag(..), Severity(..), HscTarget(..), dopt,
25 GhcMode(..), GhcLink(..), defaultObjectTarget,
26 parseDynamicFlags,
27 getSessionDynFlags,
28 setSessionDynFlags,
29 parseStaticFlags,
30
31 -- * Targets
32 Target(..), TargetId(..), Phase,
33 setTargets,
34 getTargets,
35 addTarget,
36 removeTarget,
37 guessTarget,
38
39 -- * Extending the program scope
40 extendGlobalRdrScope,
41 setGlobalRdrScope,
42 extendGlobalTypeScope,
43 setGlobalTypeScope,
44
45 -- * Loading\/compiling the program
46 depanal,
47 load, loadWithLogger, LoadHowMuch(..),
48 SuccessFlag(..), succeeded, failed,
49 defaultWarnErrLogger, WarnErrLogger,
50 workingDirectoryChanged,
51 parseModule, typecheckModule, desugarModule, loadModule,
52 ParsedModule(..), TypecheckedModule(..), DesugaredModule(..),
53 TypecheckedSource, ParsedSource, RenamedSource, -- ditto
54 TypecheckedMod, ParsedMod,
55 moduleInfo, renamedSource, typecheckedSource,
56 parsedSource, coreModule,
57 compileToCoreModule, compileToCoreSimplified,
58 compileCoreToObj,
59 getModSummary,
60
61 -- * Inspecting the module structure of the program
62 ModuleGraph, ModSummary(..), ms_mod_name, ModLocation(..),
63 getModuleGraph,
64 isLoaded,
65 topSortModuleGraph,
66
67 -- * Inspecting modules
68 ModuleInfo,
69 getModuleInfo,
70 modInfoTyThings,
71 modInfoTopLevelScope,
72 modInfoExports,
73 modInfoInstances,
74 modInfoIsExportedName,
75 modInfoLookupName,
76 lookupGlobalName,
77 findGlobalAnns,
78 mkPrintUnqualifiedForModule,
79
80 -- * Querying the environment
81 packageDbModules,
82
83 -- * Printing
84 PrintUnqualified, alwaysQualify,
85
86 -- * Interactive evaluation
87 getBindings, getPrintUnqual,
88 findModule,
89 lookupModule,
90 #ifdef GHCI
91 setContext, getContext,
92 getNamesInScope,
93 getRdrNamesInScope,
94 getGRE,
95 moduleIsInterpreted,
96 getInfo,
97 exprType,
98 typeKind,
99 parseName,
100 RunResult(..),
101 runStmt, parseImportDecl, SingleStep(..),
102 resume,
103 Resume(resumeStmt, resumeThreadId, resumeBreakInfo, resumeSpan,
104 resumeHistory, resumeHistoryIx),
105 History(historyBreakInfo, historyEnclosingDecl),
106 GHC.getHistorySpan, getHistoryModule,
107 getResumeContext,
108 abandon, abandonAll,
109 InteractiveEval.back,
110 InteractiveEval.forward,
111 showModule,
112 isModuleInterpreted,
113 InteractiveEval.compileExpr, HValue, dynCompileExpr,
114 lookupName,
115 GHC.obtainTermFromId, GHC.obtainTermFromVal, reconstructType,
116 modInfoModBreaks,
117 ModBreaks(..), BreakIndex,
118 BreakInfo(breakInfo_number, breakInfo_module),
119 BreakArray, setBreakOn, setBreakOff, getBreak,
120 #endif
121
122 -- * Abstract syntax elements
123
124 -- ** Packages
125 PackageId,
126
127 -- ** Modules
128 Module, mkModule, pprModule, moduleName, modulePackageId,
129 ModuleName, mkModuleName, moduleNameString,
130
131 -- ** Names
132 Name,
133 isExternalName, nameModule, pprParenSymName, nameSrcSpan,
134 NamedThing(..),
135 RdrName(Qual,Unqual),
136
137 -- ** Identifiers
138 Id, idType,
139 isImplicitId, isDeadBinder,
140 isExportedId, isLocalId, isGlobalId,
141 isRecordSelector,
142 isPrimOpId, isFCallId, isClassOpId_maybe,
143 isDataConWorkId, idDataCon,
144 isBottomingId, isDictonaryId,
145 recordSelectorFieldLabel,
146
147 -- ** Type constructors
148 TyCon,
149 tyConTyVars, tyConDataCons, tyConArity,
150 isClassTyCon, isSynTyCon, isNewTyCon, isPrimTyCon, isFunTyCon,
151 isOpenTyCon,
152 synTyConDefn, synTyConType, synTyConResKind,
153
154 -- ** Type variables
155 TyVar,
156 alphaTyVars,
157
158 -- ** Data constructors
159 DataCon,
160 dataConSig, dataConType, dataConTyCon, dataConFieldLabels,
161 dataConIsInfix, isVanillaDataCon, dataConUserType,
162 dataConStrictMarks,
163 StrictnessMark(..), isMarkedStrict,
164
165 -- ** Classes
166 Class,
167 classMethods, classSCTheta, classTvsFds,
168 pprFundeps,
169
170 -- ** Instances
171 Instance,
172 instanceDFunId, pprInstance, pprInstanceHdr,
173
174 -- ** Types and Kinds
175 Type, splitForAllTys, funResultTy,
176 pprParendType, pprTypeApp,
177 Kind,
178 PredType,
179 ThetaType, pprForAll, pprThetaArrow,
180
181 -- ** Entities
182 TyThing(..),
183
184 -- ** Syntax
185 module HsSyn, -- ToDo: remove extraneous bits
186
187 -- ** Fixities
188 FixityDirection(..),
189 defaultFixity, maxPrecedence,
190 negateFixity,
191 compareFixity,
192
193 -- ** Source locations
194 SrcLoc, pprDefnLoc,
195 mkSrcLoc, isGoodSrcLoc, noSrcLoc,
196 srcLocFile, srcLocLine, srcLocCol,
197 SrcSpan,
198 mkSrcSpan, srcLocSpan, isGoodSrcSpan, noSrcSpan,
199 srcSpanStart, srcSpanEnd,
200 srcSpanFile,
201 srcSpanStartLine, srcSpanEndLine,
202 srcSpanStartCol, srcSpanEndCol,
203
204 -- ** Located
205 Located(..),
206
207 -- *** Constructing Located
208 noLoc, mkGeneralLocated,
209
210 -- *** Deconstructing Located
211 getLoc, unLoc,
212
213 -- *** Combining and comparing Located values
214 eqLocated, cmpLocated, combineLocs, addCLoc,
215 leftmost_smallest, leftmost_largest, rightmost,
216 spans, isSubspanOf,
217
218 -- * Exceptions
219 GhcException(..), showGhcException,
220
221 -- * Token stream manipulations
222 Token,
223 getTokenStream, getRichTokenStream,
224 showRichTokenStream, addSourceToTokens,
225
226 -- * Miscellaneous
227 --sessionHscEnv,
228 cyclicModuleErr,
229 ) where
230
231 {-
232 ToDo:
233
234 * inline bits of HscMain here to simplify layering: hscTcExpr, hscStmt.
235 * what StaticFlags should we expose, if any?
236 -}
237
238 #include "HsVersions.h"
239
240 #ifdef GHCI
241 import qualified Linker
242 import Linker ( HValue )
243 import ByteCodeInstr
244 import BreakArray
245 import InteractiveEval
246 import TcRnDriver
247 #endif
248
249 import TcIface
250 import TcRnTypes hiding (LIE)
251 import TcRnMonad ( initIfaceCheck )
252 import Packages
253 import NameSet
254 import RdrName
255 import qualified HsSyn -- hack as we want to reexport the whole module
256 import HsSyn hiding ((<.>))
257 import Type
258 import TcType hiding( typeKind )
259 import Id
260 import Var
261 import TysPrim ( alphaTyVars )
262 import TyCon
263 import Class
264 -- import FunDeps
265 import DataCon
266 import Name hiding ( varName )
267 -- import OccName ( parenSymOcc )
268 import InstEnv ( Instance, instanceDFunId, pprInstance, pprInstanceHdr,
269 emptyInstEnv )
270 import FamInstEnv ( emptyFamInstEnv )
271 import SrcLoc
272 --import CoreSyn
273 import TidyPgm
274 import DriverPipeline
275 import DriverPhases ( Phase(..), isHaskellSrcFilename, startPhase )
276 import HeaderInfo
277 import Finder
278 import HscMain
279 import HscTypes
280 import DynFlags
281 import StaticFlagParser
282 import qualified StaticFlags
283 import SysTools ( initSysTools, cleanTempFiles, cleanTempFilesExcept,
284 cleanTempDirs )
285 import Annotations
286 import Module
287 import UniqFM
288 import FiniteMap
289 import Panic
290 import Digraph
291 import Bag ( unitBag, listToBag, emptyBag, isEmptyBag )
292 import ErrUtils
293 import MonadUtils
294 import Util
295 import StringBuffer ( StringBuffer, hGetStringBuffer, nextChar )
296 import Outputable
297 import BasicTypes
298 import Maybes ( expectJust, mapCatMaybes )
299 import FastString
300 import Lexer
301
302 import System.Directory ( getModificationTime, doesFileExist,
303 getCurrentDirectory )
304 import Data.Maybe
305 import Data.List
306 import qualified Data.List as List
307 import Data.Typeable ( Typeable )
308 import Data.Word ( Word8 )
309 import Control.Monad
310 import System.Exit ( exitWith, ExitCode(..) )
311 import System.Time ( ClockTime, getClockTime )
312 import Exception
313 import Data.IORef
314 import System.FilePath
315 import System.IO
316 import System.IO.Error ( try, isDoesNotExistError )
317 import Prelude hiding (init)
318
319
320 -- -----------------------------------------------------------------------------
321 -- Exception handlers
322
323 -- | Install some default exception handlers and run the inner computation.
324 -- Unless you want to handle exceptions yourself, you should wrap this around
325 -- the top level of your program. The default handlers output the error
326 -- message(s) to stderr and exit cleanly.
327 defaultErrorHandler :: (ExceptionMonad m, MonadIO m) => DynFlags -> m a -> m a
328 defaultErrorHandler dflags inner =
329 -- top-level exception handler: any unrecognised exception is a compiler bug.
330 ghandle (\exception -> liftIO $ do
331 hFlush stdout
332 case fromException exception of
333 -- an IO exception probably isn't our fault, so don't panic
334 Just (ioe :: IOException) ->
335 fatalErrorMsg dflags (text (show ioe))
336 _ -> case fromException exception of
337 Just UserInterrupt -> exitWith (ExitFailure 1)
338 Just StackOverflow ->
339 fatalErrorMsg dflags (text "stack overflow: use +RTS -K<size> to increase it")
340 _ -> case fromException exception of
341 Just (ex :: ExitCode) -> throw ex
342 _ ->
343 fatalErrorMsg dflags
344 (text (show (Panic (show exception))))
345 exitWith (ExitFailure 1)
346 ) $
347
348 -- error messages propagated as exceptions
349 handleGhcException
350 (\ge -> liftIO $ do
351 hFlush stdout
352 case ge of
353 PhaseFailed _ code -> exitWith code
354 Signal _ -> exitWith (ExitFailure 1)
355 _ -> do fatalErrorMsg dflags (text (show ge))
356 exitWith (ExitFailure 1)
357 ) $
358 inner
359
360 -- | Install a default cleanup handler to remove temporary files deposited by
361 -- a GHC run. This is seperate from 'defaultErrorHandler', because you might
362 -- want to override the error handling, but still get the ordinary cleanup
363 -- behaviour.
364 defaultCleanupHandler :: (ExceptionMonad m, MonadIO m) =>
365 DynFlags -> m a -> m a
366 defaultCleanupHandler dflags inner =
367 -- make sure we clean up after ourselves
368 inner `gfinally`
369 (liftIO $ do
370 cleanTempFiles dflags
371 cleanTempDirs dflags
372 )
373 -- exceptions will be blocked while we clean the temporary files,
374 -- so there shouldn't be any difficulty if we receive further
375 -- signals.
376
377 -- | Print the error message and all warnings. Useful inside exception
378 -- handlers. Clears warnings after printing.
379 printExceptionAndWarnings :: GhcMonad m => SourceError -> m ()
380 printExceptionAndWarnings err = do
381 let errs = srcErrorMessages err
382 warns <- getWarnings
383 dflags <- getSessionDynFlags
384 if isEmptyBag errs
385 -- Empty errors means we failed due to -Werror. (Since this function
386 -- takes a source error as argument, we know for sure _some_ error
387 -- did indeed happen.)
388 then liftIO $ do
389 printBagOfWarnings dflags warns
390 printBagOfErrors dflags (unitBag warnIsErrorMsg)
391 else liftIO $ printBagOfErrors dflags errs
392 clearWarnings
393
394 -- | Print all accumulated warnings using 'log_action'.
395 printWarnings :: GhcMonad m => m ()
396 printWarnings = do
397 dflags <- getSessionDynFlags
398 warns <- getWarnings
399 liftIO $ printBagOfWarnings dflags warns
400 clearWarnings
401
402 -- | Run function for the 'Ghc' monad.
403 --
404 -- It initialises the GHC session and warnings via 'initGhcMonad'. Each call
405 -- to this function will create a new session which should not be shared among
406 -- several threads.
407 --
408 -- Any errors not handled inside the 'Ghc' action are propagated as IO
409 -- exceptions.
410
411 runGhc :: Maybe FilePath -- ^ See argument to 'initGhcMonad'.
412 -> Ghc a -- ^ The action to perform.
413 -> IO a
414 runGhc mb_top_dir ghc = do
415 wref <- newIORef emptyBag
416 ref <- newIORef undefined
417 let session = Session ref wref
418 flip unGhc session $ do
419 initGhcMonad mb_top_dir
420 ghc
421 -- XXX: unregister interrupt handlers here?
422
423 -- | Run function for 'GhcT' monad transformer.
424 --
425 -- It initialises the GHC session and warnings via 'initGhcMonad'. Each call
426 -- to this function will create a new session which should not be shared among
427 -- several threads.
428
429 runGhcT :: (ExceptionMonad m, Functor m, MonadIO m) =>
430 Maybe FilePath -- ^ See argument to 'initGhcMonad'.
431 -> GhcT m a -- ^ The action to perform.
432 -> m a
433 runGhcT mb_top_dir ghct = do
434 wref <- liftIO $ newIORef emptyBag
435 ref <- liftIO $ newIORef undefined
436 let session = Session ref wref
437 flip unGhcT session $ do
438 initGhcMonad mb_top_dir
439 ghct
440
441 -- | Initialise a GHC session.
442 --
443 -- If you implement a custom 'GhcMonad' you must call this function in the
444 -- monad run function. It will initialise the session variable and clear all
445 -- warnings.
446 --
447 -- The first argument should point to the directory where GHC's library files
448 -- reside. More precisely, this should be the output of @ghc --print-libdir@
449 -- of the version of GHC the module using this API is compiled with. For
450 -- portability, you should use the @ghc-paths@ package, available at
451 -- <http://hackage.haskell.org/cgi-bin/hackage-scripts/package/ghc-paths>.
452
453 initGhcMonad :: GhcMonad m => Maybe FilePath -> m ()
454 initGhcMonad mb_top_dir = do
455 -- catch ^C
456 liftIO $ installSignalHandlers
457
458 liftIO $ StaticFlags.initStaticOpts
459
460 dflags0 <- liftIO $ initDynFlags defaultDynFlags
461 dflags <- liftIO $ initSysTools mb_top_dir dflags0
462 env <- liftIO $ newHscEnv defaultCallbacks dflags
463 setSession env
464 clearWarnings
465
466 defaultCallbacks :: GhcApiCallbacks
467 defaultCallbacks =
468 GhcApiCallbacks {
469 reportModuleCompilationResult =
470 \_ mb_err -> defaultWarnErrLogger mb_err
471 }
472
473 -- -----------------------------------------------------------------------------
474 -- Flags & settings
475
476 -- | Grabs the DynFlags from the Session
477 getSessionDynFlags :: GhcMonad m => m DynFlags
478 getSessionDynFlags = withSession (return . hsc_dflags)
479
480 -- | Updates the DynFlags in a Session. This also reads
481 -- the package database (unless it has already been read),
482 -- and prepares the compilers knowledge about packages. It
483 -- can be called again to load new packages: just add new
484 -- package flags to (packageFlags dflags).
485 --
486 -- Returns a list of new packages that may need to be linked in using
487 -- the dynamic linker (see 'linkPackages') as a result of new package
488 -- flags. If you are not doing linking or doing static linking, you
489 -- can ignore the list of packages returned.
490 --
491 setSessionDynFlags :: GhcMonad m => DynFlags -> m [PackageId]
492 setSessionDynFlags dflags = do
493 (dflags', preload) <- liftIO $ initPackages dflags
494 modifySession (\h -> h{ hsc_dflags = dflags' })
495 return preload
496
497 -- | If there is no -o option, guess the name of target executable
498 -- by using top-level source file name as a base.
499 guessOutputFile :: GhcMonad m => m ()
500 guessOutputFile = modifySession $ \env ->
501 let dflags = hsc_dflags env
502 mod_graph = hsc_mod_graph env
503 mainModuleSrcPath :: Maybe String
504 mainModuleSrcPath = do
505 let isMain = (== mainModIs dflags) . ms_mod
506 [ms] <- return (filter isMain mod_graph)
507 ml_hs_file (ms_location ms)
508 name = fmap dropExtension mainModuleSrcPath
509
510 #if defined(mingw32_HOST_OS)
511 -- we must add the .exe extention unconditionally here, otherwise
512 -- when name has an extension of its own, the .exe extension will
513 -- not be added by DriverPipeline.exeFileName. See #2248
514 name_exe = fmap (<.> "exe") name
515 #else
516 name_exe = name
517 #endif
518 in
519 case outputFile dflags of
520 Just _ -> env
521 Nothing -> env { hsc_dflags = dflags { outputFile = name_exe } }
522
523 -- -----------------------------------------------------------------------------
524 -- Targets
525
526 -- ToDo: think about relative vs. absolute file paths. And what
527 -- happens when the current directory changes.
528
529 -- | Sets the targets for this session. Each target may be a module name
530 -- or a filename. The targets correspond to the set of root modules for
531 -- the program\/library. Unloading the current program is achieved by
532 -- setting the current set of targets to be empty, followed by 'load'.
533 setTargets :: GhcMonad m => [Target] -> m ()
534 setTargets targets = modifySession (\h -> h{ hsc_targets = targets })
535
536 -- | Returns the current set of targets
537 getTargets :: GhcMonad m => m [Target]
538 getTargets = withSession (return . hsc_targets)
539
540 -- | Add another target.
541 addTarget :: GhcMonad m => Target -> m ()
542 addTarget target
543 = modifySession (\h -> h{ hsc_targets = target : hsc_targets h })
544
545 -- | Remove a target
546 removeTarget :: GhcMonad m => TargetId -> m ()
547 removeTarget target_id
548 = modifySession (\h -> h{ hsc_targets = filter (hsc_targets h) })
549 where
550 filter targets = [ t | t@(Target id _ _) <- targets, id /= target_id ]
551
552 -- | Attempts to guess what Target a string refers to. This function
553 -- implements the @--make@/GHCi command-line syntax for filenames:
554 --
555 -- - if the string looks like a Haskell source filename, then interpret it
556 -- as such
557 --
558 -- - if adding a .hs or .lhs suffix yields the name of an existing file,
559 -- then use that
560 --
561 -- - otherwise interpret the string as a module name
562 --
563 guessTarget :: GhcMonad m => String -> Maybe Phase -> m Target
564 guessTarget str (Just phase)
565 = return (Target (TargetFile str (Just phase)) True Nothing)
566 guessTarget str Nothing
567 | isHaskellSrcFilename file
568 = return (target (TargetFile file Nothing))
569 | otherwise
570 = do exists <- liftIO $ doesFileExist hs_file
571 if exists
572 then return (target (TargetFile hs_file Nothing))
573 else do
574 exists <- liftIO $ doesFileExist lhs_file
575 if exists
576 then return (target (TargetFile lhs_file Nothing))
577 else do
578 if looksLikeModuleName file
579 then return (target (TargetModule (mkModuleName file)))
580 else do
581 throwGhcException
582 (ProgramError (showSDoc $
583 text "target" <+> quotes (text file) <+>
584 text "is not a module name or a source file"))
585 where
586 (file,obj_allowed)
587 | '*':rest <- str = (rest, False)
588 | otherwise = (str, True)
589
590 hs_file = file <.> "hs"
591 lhs_file = file <.> "lhs"
592
593 target tid = Target tid obj_allowed Nothing
594
595 -- -----------------------------------------------------------------------------
596 -- Extending the program scope
597
598 extendGlobalRdrScope :: GhcMonad m => [GlobalRdrElt] -> m ()
599 extendGlobalRdrScope rdrElts
600 = modifySession $ \hscEnv ->
601 let global_rdr = hsc_global_rdr_env hscEnv
602 in hscEnv{ hsc_global_rdr_env = foldl extendGlobalRdrEnv global_rdr rdrElts }
603
604 setGlobalRdrScope :: GhcMonad m => [GlobalRdrElt] -> m ()
605 setGlobalRdrScope rdrElts
606 = modifySession $ \hscEnv ->
607 hscEnv{ hsc_global_rdr_env = foldl extendGlobalRdrEnv emptyGlobalRdrEnv rdrElts }
608
609 extendGlobalTypeScope :: GhcMonad m => [Id] -> m ()
610 extendGlobalTypeScope ids
611 = modifySession $ \hscEnv ->
612 let global_type = hsc_global_type_env hscEnv
613 in hscEnv{ hsc_global_type_env = extendTypeEnvWithIds global_type ids }
614
615 setGlobalTypeScope :: GhcMonad m => [Id] -> m ()
616 setGlobalTypeScope ids
617 = modifySession $ \hscEnv ->
618 hscEnv{ hsc_global_type_env = extendTypeEnvWithIds emptyTypeEnv ids }
619
620 -- -----------------------------------------------------------------------------
621 -- Loading the program
622
623 -- | Perform a dependency analysis starting from the current targets
624 -- and update the session with the new module graph.
625 --
626 -- Dependency analysis entails parsing the @import@ directives and may
627 -- therefore require running certain preprocessors.
628 --
629 -- Note that each 'ModSummary' in the module graph caches its 'DynFlags'.
630 -- These 'DynFlags' are determined by the /current/ session 'DynFlags' and the
631 -- @OPTIONS@ and @LANGUAGE@ pragmas of the parsed module. Thus if you want to
632 -- changes to the 'DynFlags' to take effect you need to call this function
633 -- again.
634 --
635 depanal :: GhcMonad m =>
636 [ModuleName] -- ^ excluded modules
637 -> Bool -- ^ allow duplicate roots
638 -> m ModuleGraph
639 depanal excluded_mods allow_dup_roots = do
640 hsc_env <- getSession
641 let
642 dflags = hsc_dflags hsc_env
643 targets = hsc_targets hsc_env
644 old_graph = hsc_mod_graph hsc_env
645
646 liftIO $ showPass dflags "Chasing dependencies"
647 liftIO $ debugTraceMsg dflags 2 (hcat [
648 text "Chasing modules from: ",
649 hcat (punctuate comma (map pprTarget targets))])
650
651 mod_graph <- downsweep hsc_env old_graph excluded_mods allow_dup_roots
652 modifySession $ \_ -> hsc_env { hsc_mod_graph = mod_graph }
653 return mod_graph
654
655 -- | Describes which modules of the module graph need to be loaded.
656 data LoadHowMuch
657 = LoadAllTargets
658 -- ^ Load all targets and its dependencies.
659 | LoadUpTo ModuleName
660 -- ^ Load only the given module and its dependencies.
661 | LoadDependenciesOf ModuleName
662 -- ^ Load only the dependencies of the given module, but not the module
663 -- itself.
664
665 -- | Try to load the program. See 'LoadHowMuch' for the different modes.
666 --
667 -- This function implements the core of GHC's @--make@ mode. It preprocesses,
668 -- compiles and loads the specified modules, avoiding re-compilation wherever
669 -- possible. Depending on the target (see 'DynFlags.hscTarget') compilating
670 -- and loading may result in files being created on disk.
671 --
672 -- Calls the 'reportModuleCompilationResult' callback after each compiling
673 -- each module, whether successful or not.
674 --
675 -- Throw a 'SourceError' if errors are encountered before the actual
676 -- compilation starts (e.g., during dependency analysis). All other errors
677 -- are reported using the callback.
678 --
679 load :: GhcMonad m => LoadHowMuch -> m SuccessFlag
680 load how_much = do
681 mod_graph <- depanal [] False
682 load2 how_much mod_graph
683
684 -- | A function called to log warnings and errors.
685 type WarnErrLogger = GhcMonad m => Maybe SourceError -> m ()
686
687 defaultWarnErrLogger :: WarnErrLogger
688 defaultWarnErrLogger Nothing = printWarnings
689 defaultWarnErrLogger (Just e) = printExceptionAndWarnings e
690
691 -- | Try to load the program. If a Module is supplied, then just
692 -- attempt to load up to this target. If no Module is supplied,
693 -- then try to load all targets.
694 --
695 -- The first argument is a function that is called after compiling each
696 -- module to print wanrings and errors.
697 --
698 -- While compiling a module, all 'SourceError's are caught and passed to the
699 -- logger, however, this function may still throw a 'SourceError' if
700 -- dependency analysis failed (e.g., due to a parse error).
701 --
702 loadWithLogger :: GhcMonad m => WarnErrLogger -> LoadHowMuch -> m SuccessFlag
703 loadWithLogger logger how_much = do
704 -- Dependency analysis first. Note that this fixes the module graph:
705 -- even if we don't get a fully successful upsweep, the full module
706 -- graph is still retained in the Session. We can tell which modules
707 -- were successfully loaded by inspecting the Session's HPT.
708 withLocalCallbacks (\cbs -> cbs { reportModuleCompilationResult =
709 \_ -> logger }) $
710 load how_much
711
712 load2 :: GhcMonad m => LoadHowMuch -> [ModSummary]
713 -> m SuccessFlag
714 load2 how_much mod_graph = do
715 guessOutputFile
716 hsc_env <- getSession
717
718 let hpt1 = hsc_HPT hsc_env
719 let dflags = hsc_dflags hsc_env
720
721 -- The "bad" boot modules are the ones for which we have
722 -- B.hs-boot in the module graph, but no B.hs
723 -- The downsweep should have ensured this does not happen
724 -- (see msDeps)
725 let all_home_mods = [ms_mod_name s
726 | s <- mod_graph, not (isBootSummary s)]
727 bad_boot_mods = [s | s <- mod_graph, isBootSummary s,
728 not (ms_mod_name s `elem` all_home_mods)]
729 ASSERT( null bad_boot_mods ) return ()
730
731 -- check that the module given in HowMuch actually exists, otherwise
732 -- topSortModuleGraph will bomb later.
733 let checkHowMuch (LoadUpTo m) = checkMod m
734 checkHowMuch (LoadDependenciesOf m) = checkMod m
735 checkHowMuch _ = id
736
737 checkMod m and_then
738 | m `elem` all_home_mods = and_then
739 | otherwise = do
740 liftIO $ errorMsg dflags (text "no such module:" <+>
741 quotes (ppr m))
742 return Failed
743
744 checkHowMuch how_much $ do
745
746 -- mg2_with_srcimps drops the hi-boot nodes, returning a
747 -- graph with cycles. Among other things, it is used for
748 -- backing out partially complete cycles following a failed
749 -- upsweep, and for removing from hpt all the modules
750 -- not in strict downwards closure, during calls to compile.
751 let mg2_with_srcimps :: [SCC ModSummary]
752 mg2_with_srcimps = topSortModuleGraph True mod_graph Nothing
753
754 -- If we can determine that any of the {-# SOURCE #-} imports
755 -- are definitely unnecessary, then emit a warning.
756 warnUnnecessarySourceImports mg2_with_srcimps
757
758 let
759 -- check the stability property for each module.
760 stable_mods@(stable_obj,stable_bco)
761 = checkStability hpt1 mg2_with_srcimps all_home_mods
762
763 -- prune bits of the HPT which are definitely redundant now,
764 -- to save space.
765 pruned_hpt = pruneHomePackageTable hpt1
766 (flattenSCCs mg2_with_srcimps)
767 stable_mods
768
769 _ <- liftIO $ evaluate pruned_hpt
770
771 -- before we unload anything, make sure we don't leave an old
772 -- interactive context around pointing to dead bindings. Also,
773 -- write the pruned HPT to allow the old HPT to be GC'd.
774 modifySession $ \_ -> hsc_env{ hsc_IC = emptyInteractiveContext,
775 hsc_HPT = pruned_hpt }
776
777 liftIO $ debugTraceMsg dflags 2 (text "Stable obj:" <+> ppr stable_obj $$
778 text "Stable BCO:" <+> ppr stable_bco)
779
780 -- Unload any modules which are going to be re-linked this time around.
781 let stable_linkables = [ linkable
782 | m <- stable_obj++stable_bco,
783 Just hmi <- [lookupUFM pruned_hpt m],
784 Just linkable <- [hm_linkable hmi] ]
785 liftIO $ unload hsc_env stable_linkables
786
787 -- We could at this point detect cycles which aren't broken by
788 -- a source-import, and complain immediately, but it seems better
789 -- to let upsweep_mods do this, so at least some useful work gets
790 -- done before the upsweep is abandoned.
791 --hPutStrLn stderr "after tsort:\n"
792 --hPutStrLn stderr (showSDoc (vcat (map ppr mg2)))
793
794 -- Now do the upsweep, calling compile for each module in
795 -- turn. Final result is version 3 of everything.
796
797 -- Topologically sort the module graph, this time including hi-boot
798 -- nodes, and possibly just including the portion of the graph
799 -- reachable from the module specified in the 2nd argument to load.
800 -- This graph should be cycle-free.
801 -- If we're restricting the upsweep to a portion of the graph, we
802 -- also want to retain everything that is still stable.
803 let full_mg :: [SCC ModSummary]
804 full_mg = topSortModuleGraph False mod_graph Nothing
805
806 maybe_top_mod = case how_much of
807 LoadUpTo m -> Just m
808 LoadDependenciesOf m -> Just m
809 _ -> Nothing
810
811 partial_mg0 :: [SCC ModSummary]
812 partial_mg0 = topSortModuleGraph False mod_graph maybe_top_mod
813
814 -- LoadDependenciesOf m: we want the upsweep to stop just
815 -- short of the specified module (unless the specified module
816 -- is stable).
817 partial_mg
818 | LoadDependenciesOf _mod <- how_much
819 = ASSERT( case last partial_mg0 of
820 AcyclicSCC ms -> ms_mod_name ms == _mod; _ -> False )
821 List.init partial_mg0
822 | otherwise
823 = partial_mg0
824
825 stable_mg =
826 [ AcyclicSCC ms
827 | AcyclicSCC ms <- full_mg,
828 ms_mod_name ms `elem` stable_obj++stable_bco,
829 ms_mod_name ms `notElem` [ ms_mod_name ms' |
830 AcyclicSCC ms' <- partial_mg ] ]
831
832 mg = stable_mg ++ partial_mg
833
834 -- clean up between compilations
835 let cleanup = cleanTempFilesExcept dflags
836 (ppFilesFromSummaries (flattenSCCs mg2_with_srcimps))
837
838 liftIO $ debugTraceMsg dflags 2 (hang (text "Ready for upsweep")
839 2 (ppr mg))
840 (upsweep_ok, hsc_env1, modsUpswept)
841 <- upsweep (hsc_env { hsc_HPT = emptyHomePackageTable })
842 pruned_hpt stable_mods cleanup mg
843
844 -- Make modsDone be the summaries for each home module now
845 -- available; this should equal the domain of hpt3.
846 -- Get in in a roughly top .. bottom order (hence reverse).
847
848 let modsDone = reverse modsUpswept
849
850 -- Try and do linking in some form, depending on whether the
851 -- upsweep was completely or only partially successful.
852
853 if succeeded upsweep_ok
854
855 then
856 -- Easy; just relink it all.
857 do liftIO $ debugTraceMsg dflags 2 (text "Upsweep completely successful.")
858
859 -- Clean up after ourselves
860 liftIO $ cleanTempFilesExcept dflags (ppFilesFromSummaries modsDone)
861
862 -- Issue a warning for the confusing case where the user
863 -- said '-o foo' but we're not going to do any linking.
864 -- We attempt linking if either (a) one of the modules is
865 -- called Main, or (b) the user said -no-hs-main, indicating
866 -- that main() is going to come from somewhere else.
867 --
868 let ofile = outputFile dflags
869 let no_hs_main = dopt Opt_NoHsMain dflags
870 let
871 main_mod = mainModIs dflags
872 a_root_is_Main = any ((==main_mod).ms_mod) mod_graph
873 do_linking = a_root_is_Main || no_hs_main || ghcLink dflags == LinkDynLib
874
875 when (ghcLink dflags == LinkBinary
876 && isJust ofile && not do_linking) $
877 liftIO $ debugTraceMsg dflags 1 $
878 text ("Warning: output was redirected with -o, " ++
879 "but no output will be generated\n" ++
880 "because there is no " ++
881 moduleNameString (moduleName main_mod) ++ " module.")
882
883 -- link everything together
884 linkresult <- liftIO $ link (ghcLink dflags) dflags do_linking (hsc_HPT hsc_env1)
885
886 loadFinish Succeeded linkresult hsc_env1
887
888 else
889 -- Tricky. We need to back out the effects of compiling any
890 -- half-done cycles, both so as to clean up the top level envs
891 -- and to avoid telling the interactive linker to link them.
892 do liftIO $ debugTraceMsg dflags 2 (text "Upsweep partially successful.")
893
894 let modsDone_names
895 = map ms_mod modsDone
896 let mods_to_zap_names
897 = findPartiallyCompletedCycles modsDone_names
898 mg2_with_srcimps
899 let mods_to_keep
900 = filter ((`notElem` mods_to_zap_names).ms_mod)
901 modsDone
902
903 let hpt4 = retainInTopLevelEnvs (map ms_mod_name mods_to_keep)
904 (hsc_HPT hsc_env1)
905
906 -- Clean up after ourselves
907 liftIO $ cleanTempFilesExcept dflags (ppFilesFromSummaries mods_to_keep)
908
909 -- there should be no Nothings where linkables should be, now
910 ASSERT(all (isJust.hm_linkable)
911 (eltsUFM (hsc_HPT hsc_env))) do
912
913 -- Link everything together
914 linkresult <- liftIO $ link (ghcLink dflags) dflags False hpt4
915
916 let hsc_env4 = hsc_env1{ hsc_HPT = hpt4 }
917 loadFinish Failed linkresult hsc_env4
918
919 -- Finish up after a load.
920
921 -- If the link failed, unload everything and return.
922 loadFinish :: GhcMonad m =>
923 SuccessFlag -> SuccessFlag -> HscEnv
924 -> m SuccessFlag
925 loadFinish _all_ok Failed hsc_env
926 = do liftIO $ unload hsc_env []
927 modifySession $ \_ -> discardProg hsc_env
928 return Failed
929
930 -- Empty the interactive context and set the module context to the topmost
931 -- newly loaded module, or the Prelude if none were loaded.
932 loadFinish all_ok Succeeded hsc_env
933 = do modifySession $ \_ -> hsc_env{ hsc_IC = emptyInteractiveContext }
934 return all_ok
935
936
937 -- Forget the current program, but retain the persistent info in HscEnv
938 discardProg :: HscEnv -> HscEnv
939 discardProg hsc_env
940 = hsc_env { hsc_mod_graph = emptyMG,
941 hsc_IC = emptyInteractiveContext,
942 hsc_HPT = emptyHomePackageTable }
943
944 -- used to fish out the preprocess output files for the purposes of
945 -- cleaning up. The preprocessed file *might* be the same as the
946 -- source file, but that doesn't do any harm.
947 ppFilesFromSummaries :: [ModSummary] -> [FilePath]
948 ppFilesFromSummaries summaries = map ms_hspp_file summaries
949
950 -- -----------------------------------------------------------------------------
951
952 class ParsedMod m where
953 modSummary :: m -> ModSummary
954 parsedSource :: m -> ParsedSource
955
956 class ParsedMod m => TypecheckedMod m where
957 renamedSource :: m -> Maybe RenamedSource
958 typecheckedSource :: m -> TypecheckedSource
959 moduleInfo :: m -> ModuleInfo
960 tm_internals :: m -> (TcGblEnv, ModDetails)
961 -- ToDo: improvements that could be made here:
962 -- if the module succeeded renaming but not typechecking,
963 -- we can still get back the GlobalRdrEnv and exports, so
964 -- perhaps the ModuleInfo should be split up into separate
965 -- fields.
966
967 class TypecheckedMod m => DesugaredMod m where
968 coreModule :: m -> ModGuts
969
970 -- | The result of successful parsing.
971 data ParsedModule =
972 ParsedModule { pm_mod_summary :: ModSummary
973 , pm_parsed_source :: ParsedSource }
974
975 instance ParsedMod ParsedModule where
976 modSummary m = pm_mod_summary m
977 parsedSource m = pm_parsed_source m
978
979 -- | The result of successful typechecking. It also contains the parser
980 -- result.
981 data TypecheckedModule =
982 TypecheckedModule { tm_parsed_module :: ParsedModule
983 , tm_renamed_source :: Maybe RenamedSource
984 , tm_typechecked_source :: TypecheckedSource
985 , tm_checked_module_info :: ModuleInfo
986 , tm_internals_ :: (TcGblEnv, ModDetails)
987 }
988
989 instance ParsedMod TypecheckedModule where
990 modSummary m = modSummary (tm_parsed_module m)
991 parsedSource m = parsedSource (tm_parsed_module m)
992
993 instance TypecheckedMod TypecheckedModule where
994 renamedSource m = tm_renamed_source m
995 typecheckedSource m = tm_typechecked_source m
996 moduleInfo m = tm_checked_module_info m
997 tm_internals m = tm_internals_ m
998
999 -- | The result of successful desugaring (i.e., translation to core). Also
1000 -- contains all the information of a typechecked module.
1001 data DesugaredModule =
1002 DesugaredModule { dm_typechecked_module :: TypecheckedModule
1003 , dm_core_module :: ModGuts
1004 }
1005
1006 instance ParsedMod DesugaredModule where
1007 modSummary m = modSummary (dm_typechecked_module m)
1008 parsedSource m = parsedSource (dm_typechecked_module m)
1009
1010 instance TypecheckedMod DesugaredModule where
1011 renamedSource m = renamedSource (dm_typechecked_module m)
1012 typecheckedSource m = typecheckedSource (dm_typechecked_module m)
1013 moduleInfo m = moduleInfo (dm_typechecked_module m)
1014 tm_internals m = tm_internals_ (dm_typechecked_module m)
1015
1016 instance DesugaredMod DesugaredModule where
1017 coreModule m = dm_core_module m
1018
1019 type ParsedSource = Located (HsModule RdrName)
1020 type RenamedSource = (HsGroup Name, [LImportDecl Name], Maybe [LIE Name],
1021 Maybe LHsDocString)
1022 type TypecheckedSource = LHsBinds Id
1023
1024 -- NOTE:
1025 -- - things that aren't in the output of the typechecker right now:
1026 -- - the export list
1027 -- - the imports
1028 -- - type signatures
1029 -- - type/data/newtype declarations
1030 -- - class declarations
1031 -- - instances
1032 -- - extra things in the typechecker's output:
1033 -- - default methods are turned into top-level decls.
1034 -- - dictionary bindings
1035
1036 -- | Return the 'ModSummary' of a module with the given name.
1037 --
1038 -- The module must be part of the module graph (see 'hsc_mod_graph' and
1039 -- 'ModuleGraph'). If this is not the case, this function will throw a
1040 -- 'GhcApiError'.
1041 --
1042 -- This function ignores boot modules and requires that there is only one
1043 -- non-boot module with the given name.
1044 getModSummary :: GhcMonad m => ModuleName -> m ModSummary
1045 getModSummary mod = do
1046 mg <- liftM hsc_mod_graph getSession
1047 case [ ms | ms <- mg, ms_mod_name ms == mod, not (isBootSummary ms) ] of
1048 [] -> throw $ mkApiErr (text "Module not part of module graph")
1049 [ms] -> return ms
1050 multiple -> throw $ mkApiErr (text "getModSummary is ambiguous: " <+> ppr multiple)
1051
1052 -- | Parse a module.
1053 --
1054 -- Throws a 'SourceError' on parse error.
1055 parseModule :: GhcMonad m => ModSummary -> m ParsedModule
1056 parseModule ms = do
1057 rdr_module <- withTempSession
1058 (\e -> e { hsc_dflags = ms_hspp_opts ms }) $
1059 hscParse ms
1060 return (ParsedModule ms rdr_module)
1061
1062 -- | Typecheck and rename a parsed module.
1063 --
1064 -- Throws a 'SourceError' if either fails.
1065 typecheckModule :: GhcMonad m => ParsedModule -> m TypecheckedModule
1066 typecheckModule pmod = do
1067 let ms = modSummary pmod
1068 withTempSession (\e -> e { hsc_dflags = ms_hspp_opts ms }) $ do
1069 (tc_gbl_env, rn_info)
1070 <- hscTypecheckRename ms (parsedSource pmod)
1071 details <- makeSimpleDetails tc_gbl_env
1072 return $
1073 TypecheckedModule {
1074 tm_internals_ = (tc_gbl_env, details),
1075 tm_parsed_module = pmod,
1076 tm_renamed_source = rn_info,
1077 tm_typechecked_source = tcg_binds tc_gbl_env,
1078 tm_checked_module_info =
1079 ModuleInfo {
1080 minf_type_env = md_types details,
1081 minf_exports = availsToNameSet $ md_exports details,
1082 minf_rdr_env = Just (tcg_rdr_env tc_gbl_env),
1083 minf_instances = md_insts details
1084 #ifdef GHCI
1085 ,minf_modBreaks = emptyModBreaks
1086 #endif
1087 }}
1088
1089 -- | Desugar a typechecked module.
1090 desugarModule :: GhcMonad m => TypecheckedModule -> m DesugaredModule
1091 desugarModule tcm = do
1092 let ms = modSummary tcm
1093 withTempSession (\e -> e { hsc_dflags = ms_hspp_opts ms }) $ do
1094 let (tcg, _) = tm_internals tcm
1095 guts <- hscDesugar ms tcg
1096 return $
1097 DesugaredModule {
1098 dm_typechecked_module = tcm,
1099 dm_core_module = guts
1100 }
1101
1102 -- | Load a module. Input doesn't need to be desugared.
1103 --
1104 -- A module must be loaded before dependent modules can be typechecked. This
1105 -- always includes generating a 'ModIface' and, depending on the
1106 -- 'DynFlags.hscTarget', may also include code generation.
1107 --
1108 -- This function will always cause recompilation and will always overwrite
1109 -- previous compilation results (potentially files on disk).
1110 --
1111 loadModule :: (TypecheckedMod mod, GhcMonad m) => mod -> m mod
1112 loadModule tcm = do
1113 let ms = modSummary tcm
1114 let mod = ms_mod_name ms
1115 let loc = ms_location ms
1116 let (tcg, _details) = tm_internals tcm
1117 hpt_new <-
1118 withTempSession (\e -> e { hsc_dflags = ms_hspp_opts ms }) $ do
1119
1120 let compilerBackend comp env ms' _ _mb_old_iface _ =
1121 withTempSession (\_ -> env) $
1122 hscBackend comp tcg ms' Nothing
1123
1124 hsc_env <- getSession
1125 mod_info <- do
1126 mb_linkable <-
1127 case ms_obj_date ms of
1128 Just t | t > ms_hs_date ms -> do
1129 l <- liftIO $ findObjectLinkable (ms_mod ms)
1130 (ml_obj_file loc) t
1131 return (Just l)
1132 _otherwise -> return Nothing
1133
1134 compile' (compilerBackend hscNothingCompiler
1135 ,compilerBackend hscInteractiveCompiler
1136 ,hscCheckRecompBackend hscBatchCompiler tcg)
1137 hsc_env ms 1 1 Nothing mb_linkable
1138 -- compile' shouldn't change the environment
1139 return $ addToUFM (hsc_HPT hsc_env) mod mod_info
1140 modifySession $ \e -> e{ hsc_HPT = hpt_new }
1141 return tcm
1142
1143
1144 -- | This is the way to get access to the Core bindings corresponding
1145 -- to a module. 'compileToCore' parses, typechecks, and
1146 -- desugars the module, then returns the resulting Core module (consisting of
1147 -- the module name, type declarations, and function declarations) if
1148 -- successful.
1149 compileToCoreModule :: GhcMonad m => FilePath -> m CoreModule
1150 compileToCoreModule = compileCore False
1151
1152 -- | Like compileToCoreModule, but invokes the simplifier, so
1153 -- as to return simplified and tidied Core.
1154 compileToCoreSimplified :: GhcMonad m => FilePath -> m CoreModule
1155 compileToCoreSimplified = compileCore True
1156 {-
1157 -- | Provided for backwards-compatibility: compileToCore returns just the Core
1158 -- bindings, but for most purposes, you probably want to call
1159 -- compileToCoreModule.
1160 compileToCore :: GhcMonad m => FilePath -> m [CoreBind]
1161 compileToCore fn = do
1162 mod <- compileToCoreModule session fn
1163 return $ cm_binds mod
1164 -}
1165 -- | Takes a CoreModule and compiles the bindings therein
1166 -- to object code. The first argument is a bool flag indicating
1167 -- whether to run the simplifier.
1168 -- The resulting .o, .hi, and executable files, if any, are stored in the
1169 -- current directory, and named according to the module name.
1170 -- This has only so far been tested with a single self-contained module.
1171 compileCoreToObj :: GhcMonad m => Bool -> CoreModule -> m ()
1172 compileCoreToObj simplify cm@(CoreModule{ cm_module = mName }) = do
1173 dflags <- getSessionDynFlags
1174 currentTime <- liftIO $ getClockTime
1175 cwd <- liftIO $ getCurrentDirectory
1176 modLocation <- liftIO $ mkHiOnlyModLocation dflags (hiSuf dflags) cwd
1177 ((moduleNameSlashes . moduleName) mName)
1178
1179 let modSummary = ModSummary { ms_mod = mName,
1180 ms_hsc_src = ExtCoreFile,
1181 ms_location = modLocation,
1182 -- By setting the object file timestamp to Nothing,
1183 -- we always force recompilation, which is what we
1184 -- want. (Thus it doesn't matter what the timestamp
1185 -- for the (nonexistent) source file is.)
1186 ms_hs_date = currentTime,
1187 ms_obj_date = Nothing,
1188 -- Only handling the single-module case for now, so no imports.
1189 ms_srcimps = [],
1190 ms_imps = [],
1191 -- No source file
1192 ms_hspp_file = "",
1193 ms_hspp_opts = dflags,
1194 ms_hspp_buf = Nothing
1195 }
1196
1197 let maybe_simplify mod_guts | simplify = hscSimplify mod_guts
1198 | otherwise = return mod_guts
1199 guts <- maybe_simplify (mkModGuts cm)
1200 (iface, changed, _details, cgguts)
1201 <- hscNormalIface guts Nothing
1202 hscWriteIface iface changed modSummary
1203 _ <- hscGenHardCode cgguts modSummary
1204 return ()
1205
1206 -- Makes a "vanilla" ModGuts.
1207 mkModGuts :: CoreModule -> ModGuts
1208 mkModGuts coreModule = ModGuts {
1209 mg_module = cm_module coreModule,
1210 mg_boot = False,
1211 mg_exports = [],
1212 mg_deps = noDependencies,
1213 mg_dir_imps = emptyModuleEnv,
1214 mg_used_names = emptyNameSet,
1215 mg_rdr_env = emptyGlobalRdrEnv,
1216 mg_fix_env = emptyFixityEnv,
1217 mg_types = emptyTypeEnv,
1218 mg_insts = [],
1219 mg_fam_insts = [],
1220 mg_rules = [],
1221 mg_binds = cm_binds coreModule,
1222 mg_foreign = NoStubs,
1223 mg_warns = NoWarnings,
1224 mg_anns = [],
1225 mg_hpc_info = emptyHpcInfo False,
1226 mg_modBreaks = emptyModBreaks,
1227 mg_vect_info = noVectInfo,
1228 mg_inst_env = emptyInstEnv,
1229 mg_fam_inst_env = emptyFamInstEnv
1230 }
1231
1232 compileCore :: GhcMonad m => Bool -> FilePath -> m CoreModule
1233 compileCore simplify fn = do
1234 -- First, set the target to the desired filename
1235 target <- guessTarget fn Nothing
1236 addTarget target
1237 _ <- load LoadAllTargets
1238 -- Then find dependencies
1239 modGraph <- depanal [] True
1240 case find ((== fn) . msHsFilePath) modGraph of
1241 Just modSummary -> do
1242 -- Now we have the module name;
1243 -- parse, typecheck and desugar the module
1244 mod_guts <- coreModule `fmap`
1245 -- TODO: space leaky: call hsc* directly?
1246 (desugarModule =<< typecheckModule =<< parseModule modSummary)
1247 liftM gutsToCoreModule $
1248 if simplify
1249 then do
1250 -- If simplify is true: simplify (hscSimplify), then tidy
1251 -- (tidyProgram).
1252 hsc_env <- getSession
1253 simpl_guts <- hscSimplify mod_guts
1254 tidy_guts <- liftIO $ tidyProgram hsc_env simpl_guts
1255 return $ Left tidy_guts
1256 else
1257 return $ Right mod_guts
1258
1259 Nothing -> panic "compileToCoreModule: target FilePath not found in\
1260 module dependency graph"
1261 where -- two versions, based on whether we simplify (thus run tidyProgram,
1262 -- which returns a (CgGuts, ModDetails) pair, or not (in which case
1263 -- we just have a ModGuts.
1264 gutsToCoreModule :: Either (CgGuts, ModDetails) ModGuts -> CoreModule
1265 gutsToCoreModule (Left (cg, md)) = CoreModule {
1266 cm_module = cg_module cg, cm_types = md_types md,
1267 cm_imports = cg_dir_imps cg, cm_binds = cg_binds cg
1268 }
1269 gutsToCoreModule (Right mg) = CoreModule {
1270 cm_module = mg_module mg, cm_types = mg_types mg,
1271 cm_imports = moduleEnvKeys (mg_dir_imps mg), cm_binds = mg_binds mg
1272 }
1273
1274 -- ---------------------------------------------------------------------------
1275 -- Unloading
1276
1277 unload :: HscEnv -> [Linkable] -> IO ()
1278 unload hsc_env stable_linkables -- Unload everthing *except* 'stable_linkables'
1279 = case ghcLink (hsc_dflags hsc_env) of
1280 #ifdef GHCI
1281 LinkInMemory -> Linker.unload (hsc_dflags hsc_env) stable_linkables
1282 #else
1283 LinkInMemory -> panic "unload: no interpreter"
1284 -- urgh. avoid warnings:
1285 hsc_env stable_linkables
1286 #endif
1287 _other -> return ()
1288
1289 -- -----------------------------------------------------------------------------
1290
1291 {- |
1292
1293 Stability tells us which modules definitely do not need to be recompiled.
1294 There are two main reasons for having stability:
1295
1296 - avoid doing a complete upsweep of the module graph in GHCi when
1297 modules near the bottom of the tree have not changed.
1298
1299 - to tell GHCi when it can load object code: we can only load object code
1300 for a module when we also load object code fo all of the imports of the
1301 module. So we need to know that we will definitely not be recompiling
1302 any of these modules, and we can use the object code.
1303
1304 The stability check is as follows. Both stableObject and
1305 stableBCO are used during the upsweep phase later.
1306
1307 @
1308 stable m = stableObject m || stableBCO m
1309
1310 stableObject m =
1311 all stableObject (imports m)
1312 && old linkable does not exist, or is == on-disk .o
1313 && date(on-disk .o) > date(.hs)
1314
1315 stableBCO m =
1316 all stable (imports m)
1317 && date(BCO) > date(.hs)
1318 @
1319
1320 These properties embody the following ideas:
1321
1322 - if a module is stable, then:
1323
1324 - if it has been compiled in a previous pass (present in HPT)
1325 then it does not need to be compiled or re-linked.
1326
1327 - if it has not been compiled in a previous pass,
1328 then we only need to read its .hi file from disk and
1329 link it to produce a 'ModDetails'.
1330
1331 - if a modules is not stable, we will definitely be at least
1332 re-linking, and possibly re-compiling it during the 'upsweep'.
1333 All non-stable modules can (and should) therefore be unlinked
1334 before the 'upsweep'.
1335
1336 - Note that objects are only considered stable if they only depend
1337 on other objects. We can't link object code against byte code.
1338 -}
1339
1340 checkStability
1341 :: HomePackageTable -- HPT from last compilation
1342 -> [SCC ModSummary] -- current module graph (cyclic)
1343 -> [ModuleName] -- all home modules
1344 -> ([ModuleName], -- stableObject
1345 [ModuleName]) -- stableBCO
1346
1347 checkStability hpt sccs all_home_mods = foldl checkSCC ([],[]) sccs
1348 where
1349 checkSCC (stable_obj, stable_bco) scc0
1350 | stableObjects = (scc_mods ++ stable_obj, stable_bco)
1351 | stableBCOs = (stable_obj, scc_mods ++ stable_bco)
1352 | otherwise = (stable_obj, stable_bco)
1353 where
1354 scc = flattenSCC scc0
1355 scc_mods = map ms_mod_name scc
1356 home_module m = m `elem` all_home_mods && m `notElem` scc_mods
1357
1358 scc_allimps = nub (filter home_module (concatMap ms_home_allimps scc))
1359 -- all imports outside the current SCC, but in the home pkg
1360
1361 stable_obj_imps = map (`elem` stable_obj) scc_allimps
1362 stable_bco_imps = map (`elem` stable_bco) scc_allimps
1363
1364 stableObjects =
1365 and stable_obj_imps
1366 && all object_ok scc
1367
1368 stableBCOs =
1369 and (zipWith (||) stable_obj_imps stable_bco_imps)
1370 && all bco_ok scc
1371
1372 object_ok ms
1373 | Just t <- ms_obj_date ms = t >= ms_hs_date ms
1374 && same_as_prev t
1375 | otherwise = False
1376 where
1377 same_as_prev t = case lookupUFM hpt (ms_mod_name ms) of
1378 Just hmi | Just l <- hm_linkable hmi
1379 -> isObjectLinkable l && t == linkableTime l
1380 _other -> True
1381 -- why '>=' rather than '>' above? If the filesystem stores
1382 -- times to the nearset second, we may occasionally find that
1383 -- the object & source have the same modification time,
1384 -- especially if the source was automatically generated
1385 -- and compiled. Using >= is slightly unsafe, but it matches
1386 -- make's behaviour.
1387
1388 bco_ok ms
1389 = case lookupUFM hpt (ms_mod_name ms) of
1390 Just hmi | Just l <- hm_linkable hmi ->
1391 not (isObjectLinkable l) &&
1392 linkableTime l >= ms_hs_date ms
1393 _other -> False
1394
1395 -- -----------------------------------------------------------------------------
1396
1397 -- | Prune the HomePackageTable
1398 --
1399 -- Before doing an upsweep, we can throw away:
1400 --
1401 -- - For non-stable modules:
1402 -- - all ModDetails, all linked code
1403 -- - all unlinked code that is out of date with respect to
1404 -- the source file
1405 --
1406 -- This is VERY IMPORTANT otherwise we'll end up requiring 2x the
1407 -- space at the end of the upsweep, because the topmost ModDetails of the
1408 -- old HPT holds on to the entire type environment from the previous
1409 -- compilation.
1410
1411 pruneHomePackageTable
1412 :: HomePackageTable
1413 -> [ModSummary]
1414 -> ([ModuleName],[ModuleName])
1415 -> HomePackageTable
1416
1417 pruneHomePackageTable hpt summ (stable_obj, stable_bco)
1418 = mapUFM prune hpt
1419 where prune hmi
1420 | is_stable modl = hmi'
1421 | otherwise = hmi'{ hm_details = emptyModDetails }
1422 where
1423 modl = moduleName (mi_module (hm_iface hmi))
1424 hmi' | Just l <- hm_linkable hmi, linkableTime l < ms_hs_date ms
1425 = hmi{ hm_linkable = Nothing }
1426 | otherwise
1427 = hmi
1428 where ms = expectJust "prune" (lookupUFM ms_map modl)
1429
1430 ms_map = listToUFM [(ms_mod_name ms, ms) | ms <- summ]
1431
1432 is_stable m = m `elem` stable_obj || m `elem` stable_bco
1433
1434 -- -----------------------------------------------------------------------------
1435
1436 -- Return (names of) all those in modsDone who are part of a cycle
1437 -- as defined by theGraph.
1438 findPartiallyCompletedCycles :: [Module] -> [SCC ModSummary] -> [Module]
1439 findPartiallyCompletedCycles modsDone theGraph
1440 = chew theGraph
1441 where
1442 chew [] = []
1443 chew ((AcyclicSCC _):rest) = chew rest -- acyclic? not interesting.
1444 chew ((CyclicSCC vs):rest)
1445 = let names_in_this_cycle = nub (map ms_mod vs)
1446 mods_in_this_cycle
1447 = nub ([done | done <- modsDone,
1448 done `elem` names_in_this_cycle])
1449 chewed_rest = chew rest
1450 in
1451 if notNull mods_in_this_cycle
1452 && length mods_in_this_cycle < length names_in_this_cycle
1453 then mods_in_this_cycle ++ chewed_rest
1454 else chewed_rest
1455
1456 -- -----------------------------------------------------------------------------
1457
1458 -- | The upsweep
1459 --
1460 -- This is where we compile each module in the module graph, in a pass
1461 -- from the bottom to the top of the graph.
1462 --
1463 -- There better had not be any cyclic groups here -- we check for them.
1464
1465 upsweep
1466 :: GhcMonad m =>
1467 HscEnv -- ^ Includes initially-empty HPT
1468 -> HomePackageTable -- ^ HPT from last time round (pruned)
1469 -> ([ModuleName],[ModuleName]) -- ^ stable modules (see checkStability)
1470 -> IO () -- ^ How to clean up unwanted tmp files
1471 -> [SCC ModSummary] -- ^ Mods to do (the worklist)
1472 -> m (SuccessFlag,
1473 HscEnv,
1474 [ModSummary])
1475 -- ^ Returns:
1476 --
1477 -- 1. A flag whether the complete upsweep was successful.
1478 -- 2. The 'HscEnv' with an updated HPT
1479 -- 3. A list of modules which succeeded loading.
1480
1481 upsweep hsc_env old_hpt stable_mods cleanup sccs = do
1482 (res, hsc_env, done) <- upsweep' hsc_env old_hpt [] sccs 1 (length sccs)
1483 return (res, hsc_env, reverse done)
1484 where
1485
1486 upsweep' hsc_env _old_hpt done
1487 [] _ _
1488 = return (Succeeded, hsc_env, done)
1489
1490 upsweep' hsc_env _old_hpt done
1491 (CyclicSCC ms:_) _ _
1492 = do liftIO $ fatalErrorMsg (hsc_dflags hsc_env) (cyclicModuleErr ms)
1493 return (Failed, hsc_env, done)
1494
1495 upsweep' hsc_env old_hpt done
1496 (AcyclicSCC mod:mods) mod_index nmods
1497 = do -- putStrLn ("UPSWEEP_MOD: hpt = " ++
1498 -- show (map (moduleUserString.moduleName.mi_module.hm_iface)
1499 -- (moduleEnvElts (hsc_HPT hsc_env)))
1500 let logger = reportModuleCompilationResult (hsc_callbacks hsc_env)
1501
1502 mb_mod_info
1503 <- handleSourceError
1504 (\err -> do logger mod (Just err); return Nothing) $ do
1505 mod_info <- upsweep_mod hsc_env old_hpt stable_mods
1506 mod mod_index nmods
1507 logger mod Nothing -- log warnings
1508 return (Just mod_info)
1509
1510 liftIO cleanup -- Remove unwanted tmp files between compilations
1511
1512 case mb_mod_info of
1513 Nothing -> return (Failed, hsc_env, done)
1514 Just mod_info -> do
1515 let this_mod = ms_mod_name mod
1516
1517 -- Add new info to hsc_env
1518 hpt1 = addToUFM (hsc_HPT hsc_env) this_mod mod_info
1519 hsc_env1 = hsc_env { hsc_HPT = hpt1 }
1520
1521 -- Space-saving: delete the old HPT entry
1522 -- for mod BUT if mod is a hs-boot
1523 -- node, don't delete it. For the
1524 -- interface, the HPT entry is probaby for the
1525 -- main Haskell source file. Deleting it
1526 -- would force the real module to be recompiled
1527 -- every time.
1528 old_hpt1 | isBootSummary mod = old_hpt
1529 | otherwise = delFromUFM old_hpt this_mod
1530
1531 done' = mod:done
1532
1533 -- fixup our HomePackageTable after we've finished compiling
1534 -- a mutually-recursive loop. See reTypecheckLoop, below.
1535 hsc_env2 <- liftIO $ reTypecheckLoop hsc_env1 mod done'
1536
1537 upsweep' hsc_env2 old_hpt1 done' mods (mod_index+1) nmods
1538
1539 -- | Compile a single module. Always produce a Linkable for it if
1540 -- successful. If no compilation happened, return the old Linkable.
1541 upsweep_mod :: GhcMonad m =>
1542 HscEnv
1543 -> HomePackageTable
1544 -> ([ModuleName],[ModuleName])
1545 -> ModSummary
1546 -> Int -- index of module
1547 -> Int -- total number of modules
1548 -> m HomeModInfo
1549
1550 upsweep_mod hsc_env old_hpt (stable_obj, stable_bco) summary mod_index nmods
1551 = let
1552 this_mod_name = ms_mod_name summary
1553 this_mod = ms_mod summary
1554 mb_obj_date = ms_obj_date summary
1555 obj_fn = ml_obj_file (ms_location summary)
1556 hs_date = ms_hs_date summary
1557
1558 is_stable_obj = this_mod_name `elem` stable_obj
1559 is_stable_bco = this_mod_name `elem` stable_bco
1560
1561 old_hmi = lookupUFM old_hpt this_mod_name
1562
1563 -- We're using the dflags for this module now, obtained by
1564 -- applying any options in its LANGUAGE & OPTIONS_GHC pragmas.
1565 dflags = ms_hspp_opts summary
1566 prevailing_target = hscTarget (hsc_dflags hsc_env)
1567 local_target = hscTarget dflags
1568
1569 -- If OPTIONS_GHC contains -fasm or -fvia-C, be careful that
1570 -- we don't do anything dodgy: these should only work to change
1571 -- from -fvia-C to -fasm and vice-versa, otherwise we could
1572 -- end up trying to link object code to byte code.
1573 target = if prevailing_target /= local_target
1574 && (not (isObjectTarget prevailing_target)
1575 || not (isObjectTarget local_target))
1576 then prevailing_target
1577 else local_target
1578
1579 -- store the corrected hscTarget into the summary
1580 summary' = summary{ ms_hspp_opts = dflags { hscTarget = target } }
1581
1582 -- The old interface is ok if
1583 -- a) we're compiling a source file, and the old HPT
1584 -- entry is for a source file
1585 -- b) we're compiling a hs-boot file
1586 -- Case (b) allows an hs-boot file to get the interface of its
1587 -- real source file on the second iteration of the compilation
1588 -- manager, but that does no harm. Otherwise the hs-boot file
1589 -- will always be recompiled
1590
1591 mb_old_iface
1592 = case old_hmi of
1593 Nothing -> Nothing
1594 Just hm_info | isBootSummary summary -> Just iface
1595 | not (mi_boot iface) -> Just iface
1596 | otherwise -> Nothing
1597 where
1598 iface = hm_iface hm_info
1599
1600 compile_it :: GhcMonad m => Maybe Linkable -> m HomeModInfo
1601 compile_it = compile hsc_env summary' mod_index nmods mb_old_iface
1602
1603 compile_it_discard_iface :: GhcMonad m =>
1604 Maybe Linkable -> m HomeModInfo
1605 compile_it_discard_iface
1606 = compile hsc_env summary' mod_index nmods Nothing
1607
1608 -- With the HscNothing target we create empty linkables to avoid
1609 -- recompilation. We have to detect these to recompile anyway if
1610 -- the target changed since the last compile.
1611 is_fake_linkable
1612 | Just hmi <- old_hmi, Just l <- hm_linkable hmi =
1613 null (linkableUnlinked l)
1614 | otherwise =
1615 -- we have no linkable, so it cannot be fake
1616 False
1617
1618 implies False _ = True
1619 implies True x = x
1620
1621 in
1622 case () of
1623 _
1624 -- Regardless of whether we're generating object code or
1625 -- byte code, we can always use an existing object file
1626 -- if it is *stable* (see checkStability).
1627 | is_stable_obj, Just hmi <- old_hmi -> do
1628 liftIO $ debugTraceMsg (hsc_dflags hsc_env) 5
1629 (text "skipping stable obj mod:" <+> ppr this_mod_name)
1630 return hmi
1631 -- object is stable, and we have an entry in the
1632 -- old HPT: nothing to do
1633
1634 | is_stable_obj, isNothing old_hmi -> do
1635 liftIO $ debugTraceMsg (hsc_dflags hsc_env) 5
1636 (text "compiling stable on-disk mod:" <+> ppr this_mod_name)
1637 linkable <- liftIO $ findObjectLinkable this_mod obj_fn
1638 (expectJust "upsweep1" mb_obj_date)
1639 compile_it (Just linkable)
1640 -- object is stable, but we need to load the interface
1641 -- off disk to make a HMI.
1642
1643 | not (isObjectTarget target), is_stable_bco,
1644 (target /= HscNothing) `implies` not is_fake_linkable ->
1645 ASSERT(isJust old_hmi) -- must be in the old_hpt
1646 let Just hmi = old_hmi in do
1647 liftIO $ debugTraceMsg (hsc_dflags hsc_env) 5
1648 (text "skipping stable BCO mod:" <+> ppr this_mod_name)
1649 return hmi
1650 -- BCO is stable: nothing to do
1651
1652 | not (isObjectTarget target),
1653 Just hmi <- old_hmi,
1654 Just l <- hm_linkable hmi,
1655 not (isObjectLinkable l),
1656 (target /= HscNothing) `implies` not is_fake_linkable,
1657 linkableTime l >= ms_hs_date summary -> do
1658 liftIO $ debugTraceMsg (hsc_dflags hsc_env) 5
1659 (text "compiling non-stable BCO mod:" <+> ppr this_mod_name)
1660 compile_it (Just l)
1661 -- we have an old BCO that is up to date with respect
1662 -- to the source: do a recompilation check as normal.
1663
1664 -- When generating object code, if there's an up-to-date
1665 -- object file on the disk, then we can use it.
1666 -- However, if the object file is new (compared to any
1667 -- linkable we had from a previous compilation), then we
1668 -- must discard any in-memory interface, because this
1669 -- means the user has compiled the source file
1670 -- separately and generated a new interface, that we must
1671 -- read from the disk.
1672 --
1673 | isObjectTarget target,
1674 Just obj_date <- mb_obj_date,
1675 obj_date >= hs_date -> do
1676 case old_hmi of
1677 Just hmi
1678 | Just l <- hm_linkable hmi,
1679 isObjectLinkable l && linkableTime l == obj_date -> do
1680 liftIO $ debugTraceMsg (hsc_dflags hsc_env) 5
1681 (text "compiling mod with new on-disk obj:" <+> ppr this_mod_name)
1682 compile_it (Just l)
1683 _otherwise -> do
1684 liftIO $ debugTraceMsg (hsc_dflags hsc_env) 5
1685 (text "compiling mod with new on-disk obj2:" <+> ppr this_mod_name)
1686 linkable <- liftIO $ findObjectLinkable this_mod obj_fn obj_date
1687 compile_it_discard_iface (Just linkable)
1688
1689 _otherwise -> do
1690 liftIO $ debugTraceMsg (hsc_dflags hsc_env) 5
1691 (text "compiling mod:" <+> ppr this_mod_name)
1692 compile_it Nothing
1693
1694
1695
1696 -- Filter modules in the HPT
1697 retainInTopLevelEnvs :: [ModuleName] -> HomePackageTable -> HomePackageTable
1698 retainInTopLevelEnvs keep_these hpt
1699 = listToUFM [ (mod, expectJust "retain" mb_mod_info)
1700 | mod <- keep_these
1701 , let mb_mod_info = lookupUFM hpt mod
1702 , isJust mb_mod_info ]
1703
1704 -- ---------------------------------------------------------------------------
1705 -- Typecheck module loops
1706
1707 {-
1708 See bug #930. This code fixes a long-standing bug in --make. The
1709 problem is that when compiling the modules *inside* a loop, a data
1710 type that is only defined at the top of the loop looks opaque; but
1711 after the loop is done, the structure of the data type becomes
1712 apparent.
1713
1714 The difficulty is then that two different bits of code have
1715 different notions of what the data type looks like.
1716
1717 The idea is that after we compile a module which also has an .hs-boot
1718 file, we re-generate the ModDetails for each of the modules that
1719 depends on the .hs-boot file, so that everyone points to the proper
1720 TyCons, Ids etc. defined by the real module, not the boot module.
1721 Fortunately re-generating a ModDetails from a ModIface is easy: the
1722 function TcIface.typecheckIface does exactly that.
1723
1724 Picking the modules to re-typecheck is slightly tricky. Starting from
1725 the module graph consisting of the modules that have already been
1726 compiled, we reverse the edges (so they point from the imported module
1727 to the importing module), and depth-first-search from the .hs-boot
1728 node. This gives us all the modules that depend transitively on the
1729 .hs-boot module, and those are exactly the modules that we need to
1730 re-typecheck.
1731
1732 Following this fix, GHC can compile itself with --make -O2.
1733 -}
1734
1735 reTypecheckLoop :: HscEnv -> ModSummary -> ModuleGraph -> IO HscEnv
1736 reTypecheckLoop hsc_env ms graph
1737 | not (isBootSummary ms) &&
1738 any (\m -> ms_mod m == this_mod && isBootSummary m) graph
1739 = do
1740 let mss = reachableBackwards (ms_mod_name ms) graph
1741 non_boot = filter (not.isBootSummary) mss
1742 debugTraceMsg (hsc_dflags hsc_env) 2 $
1743 text "Re-typechecking loop: " <> ppr (map ms_mod_name non_boot)
1744 typecheckLoop hsc_env (map ms_mod_name non_boot)
1745 | otherwise
1746 = return hsc_env
1747 where
1748 this_mod = ms_mod ms
1749
1750 typecheckLoop :: HscEnv -> [ModuleName] -> IO HscEnv
1751 typecheckLoop hsc_env mods = do
1752 new_hpt <-
1753 fixIO $ \new_hpt -> do
1754 let new_hsc_env = hsc_env{ hsc_HPT = new_hpt }
1755 mds <- initIfaceCheck new_hsc_env $
1756 mapM (typecheckIface . hm_iface) hmis
1757 let new_hpt = addListToUFM old_hpt
1758 (zip mods [ hmi{ hm_details = details }
1759 | (hmi,details) <- zip hmis mds ])
1760 return new_hpt
1761 return hsc_env{ hsc_HPT = new_hpt }
1762 where
1763 old_hpt = hsc_HPT hsc_env
1764 hmis = map (expectJust "typecheckLoop" . lookupUFM old_hpt) mods
1765
1766 reachableBackwards :: ModuleName -> [ModSummary] -> [ModSummary]
1767 reachableBackwards mod summaries
1768 = [ ms | (ms,_,_) <- reachableG (transposeG graph) root ]
1769 where -- the rest just sets up the graph:
1770 (graph, lookup_node) = moduleGraphNodes False summaries
1771 root = expectJust "reachableBackwards" (lookup_node HsBootFile mod)
1772
1773 -- ---------------------------------------------------------------------------
1774 -- Topological sort of the module graph
1775
1776 type SummaryNode = (ModSummary, Int, [Int])
1777
1778 topSortModuleGraph
1779 :: Bool
1780 -- ^ Drop hi-boot nodes? (see below)
1781 -> [ModSummary]
1782 -> Maybe ModuleName
1783 -- ^ Root module name. If @Nothing@, use the full graph.
1784 -> [SCC ModSummary]
1785 -- ^ Calculate SCCs of the module graph, possibly dropping the hi-boot nodes
1786 -- The resulting list of strongly-connected-components is in topologically
1787 -- sorted order, starting with the module(s) at the bottom of the
1788 -- dependency graph (ie compile them first) and ending with the ones at
1789 -- the top.
1790 --
1791 -- Drop hi-boot nodes (first boolean arg)?
1792 --
1793 -- - @False@: treat the hi-boot summaries as nodes of the graph,
1794 -- so the graph must be acyclic
1795 --
1796 -- - @True@: eliminate the hi-boot nodes, and instead pretend
1797 -- the a source-import of Foo is an import of Foo
1798 -- The resulting graph has no hi-boot nodes, but can be cyclic
1799
1800 topSortModuleGraph drop_hs_boot_nodes summaries mb_root_mod
1801 = map (fmap summaryNodeSummary) $ stronglyConnCompG initial_graph
1802 where
1803 (graph, lookup_node) = moduleGraphNodes drop_hs_boot_nodes summaries
1804
1805 initial_graph = case mb_root_mod of
1806 Nothing -> graph
1807 Just root_mod ->
1808 -- restrict the graph to just those modules reachable from
1809 -- the specified module. We do this by building a graph with
1810 -- the full set of nodes, and determining the reachable set from
1811 -- the specified node.
1812 let root | Just node <- lookup_node HsSrcFile root_mod, graph `hasVertexG` node = node
1813 | otherwise = ghcError (ProgramError "module does not exist")
1814 in graphFromEdgedVertices (seq root (reachableG graph root))
1815
1816 summaryNodeKey :: SummaryNode -> Int
1817 summaryNodeKey (_, k, _) = k
1818
1819 summaryNodeSummary :: SummaryNode -> ModSummary
1820 summaryNodeSummary (s, _, _) = s
1821
1822 moduleGraphNodes :: Bool -> [ModSummary]
1823 -> (Graph SummaryNode, HscSource -> ModuleName -> Maybe SummaryNode)
1824 moduleGraphNodes drop_hs_boot_nodes summaries = (graphFromEdgedVertices nodes, lookup_node)
1825 where
1826 numbered_summaries = zip summaries [1..]
1827
1828 lookup_node :: HscSource -> ModuleName -> Maybe SummaryNode
1829 lookup_node hs_src mod = lookupFM node_map (mod, hs_src)
1830
1831 lookup_key :: HscSource -> ModuleName -> Maybe Int
1832 lookup_key hs_src mod = fmap summaryNodeKey (lookup_node hs_src mod)
1833
1834 node_map :: NodeMap SummaryNode
1835 node_map = listToFM [ ((moduleName (ms_mod s), ms_hsc_src s), node)
1836 | node@(s, _, _) <- nodes ]
1837
1838 -- We use integers as the keys for the SCC algorithm
1839 nodes :: [SummaryNode]
1840 nodes = [ (s, key, out_keys)
1841 | (s, key) <- numbered_summaries
1842 -- Drop the hi-boot ones if told to do so
1843 , not (isBootSummary s && drop_hs_boot_nodes)
1844 , let out_keys = out_edge_keys hs_boot_key (map unLoc (ms_home_srcimps s)) ++
1845 out_edge_keys HsSrcFile (map unLoc (ms_home_imps s)) ++
1846 (-- see [boot-edges] below
1847 if drop_hs_boot_nodes || ms_hsc_src s == HsBootFile
1848 then []
1849 else case lookup_key HsBootFile (ms_mod_name s) of
1850 Nothing -> []
1851 Just k -> [k]) ]
1852
1853 -- [boot-edges] if this is a .hs and there is an equivalent
1854 -- .hs-boot, add a link from the former to the latter. This
1855 -- has the effect of detecting bogus cases where the .hs-boot
1856 -- depends on the .hs, by introducing a cycle. Additionally,
1857 -- it ensures that we will always process the .hs-boot before
1858 -- the .hs, and so the HomePackageTable will always have the
1859 -- most up to date information.
1860
1861 -- Drop hs-boot nodes by using HsSrcFile as the key
1862 hs_boot_key | drop_hs_boot_nodes = HsSrcFile
1863 | otherwise = HsBootFile
1864
1865 out_edge_keys :: HscSource -> [ModuleName] -> [Int]
1866 out_edge_keys hi_boot ms = mapCatMaybes (lookup_key hi_boot) ms
1867 -- If we want keep_hi_boot_nodes, then we do lookup_key with
1868 -- the IsBootInterface parameter True; else False
1869
1870
1871 type NodeKey = (ModuleName, HscSource) -- The nodes of the graph are
1872 type NodeMap a = FiniteMap NodeKey a -- keyed by (mod, src_file_type) pairs
1873
1874 msKey :: ModSummary -> NodeKey
1875 msKey (ModSummary { ms_mod = mod, ms_hsc_src = boot }) = (moduleName mod,boot)
1876
1877 mkNodeMap :: [ModSummary] -> NodeMap ModSummary
1878 mkNodeMap summaries = listToFM [ (msKey s, s) | s <- summaries]
1879
1880 nodeMapElts :: NodeMap a -> [a]
1881 nodeMapElts = eltsFM
1882
1883 -- | If there are {-# SOURCE #-} imports between strongly connected
1884 -- components in the topological sort, then those imports can
1885 -- definitely be replaced by ordinary non-SOURCE imports: if SOURCE
1886 -- were necessary, then the edge would be part of a cycle.
1887 warnUnnecessarySourceImports :: GhcMonad m => [SCC ModSummary] -> m ()
1888 warnUnnecessarySourceImports sccs =
1889 logWarnings (listToBag (concatMap (check.flattenSCC) sccs))
1890 where check ms =
1891 let mods_in_this_cycle = map ms_mod_name ms in
1892 [ warn i | m <- ms, i <- ms_home_srcimps m,
1893 unLoc i `notElem` mods_in_this_cycle ]
1894
1895 warn :: Located ModuleName -> WarnMsg
1896 warn (L loc mod) =
1897 mkPlainErrMsg loc
1898 (ptext (sLit "Warning: {-# SOURCE #-} unnecessary in import of ")
1899 <+> quotes (ppr mod))
1900
1901 -----------------------------------------------------------------------------
1902 -- Downsweep (dependency analysis)
1903
1904 -- Chase downwards from the specified root set, returning summaries
1905 -- for all home modules encountered. Only follow source-import
1906 -- links.
1907
1908 -- We pass in the previous collection of summaries, which is used as a
1909 -- cache to avoid recalculating a module summary if the source is
1910 -- unchanged.
1911 --
1912 -- The returned list of [ModSummary] nodes has one node for each home-package
1913 -- module, plus one for any hs-boot files. The imports of these nodes
1914 -- are all there, including the imports of non-home-package modules.
1915
1916 downsweep :: GhcMonad m =>
1917 HscEnv
1918 -> [ModSummary] -- Old summaries
1919 -> [ModuleName] -- Ignore dependencies on these; treat
1920 -- them as if they were package modules
1921 -> Bool -- True <=> allow multiple targets to have
1922 -- the same module name; this is
1923 -- very useful for ghc -M
1924 -> m [ModSummary]
1925 -- The elts of [ModSummary] all have distinct
1926 -- (Modules, IsBoot) identifiers, unless the Bool is true
1927 -- in which case there can be repeats
1928 downsweep hsc_env old_summaries excl_mods allow_dup_roots
1929 = do -- catch error messages and return them
1930 --handleErrMsg -- should be covered by GhcMonad now
1931 -- (\err_msg -> printBagOfErrors (hsc_dflags hsc_env) (unitBag err_msg) >> return Nothing) $ do
1932 rootSummaries <- mapM getRootSummary roots
1933 let root_map = mkRootMap rootSummaries
1934 checkDuplicates root_map
1935 summs <- loop (concatMap msDeps rootSummaries) root_map
1936 return summs
1937 where
1938 roots = hsc_targets hsc_env
1939
1940 old_summary_map :: NodeMap ModSummary
1941 old_summary_map = mkNodeMap old_summaries
1942
1943 getRootSummary :: GhcMonad m => Target -> m ModSummary
1944 getRootSummary (Target (TargetFile file mb_phase) obj_allowed maybe_buf)
1945 = do exists <- liftIO $ doesFileExist file
1946 if exists
1947 then summariseFile hsc_env old_summaries file mb_phase
1948 obj_allowed maybe_buf
1949 else throwOneError $ mkPlainErrMsg noSrcSpan $
1950 text "can't find file:" <+> text file
1951 getRootSummary (Target (TargetModule modl) obj_allowed maybe_buf)
1952 = do maybe_summary <- summariseModule hsc_env old_summary_map False
1953 (L rootLoc modl) obj_allowed
1954 maybe_buf excl_mods
1955 case maybe_summary of
1956 Nothing -> packageModErr modl
1957 Just s -> return s
1958
1959 rootLoc = mkGeneralSrcSpan (fsLit "<command line>")
1960
1961 -- In a root module, the filename is allowed to diverge from the module
1962 -- name, so we have to check that there aren't multiple root files
1963 -- defining the same module (otherwise the duplicates will be silently
1964 -- ignored, leading to confusing behaviour).
1965 checkDuplicates :: GhcMonad m => NodeMap [ModSummary] -> m ()
1966 checkDuplicates root_map
1967 | allow_dup_roots = return ()
1968 | null dup_roots = return ()
1969 | otherwise = liftIO $ multiRootsErr (head dup_roots)
1970 where
1971 dup_roots :: [[ModSummary]] -- Each at least of length 2
1972 dup_roots = filterOut isSingleton (nodeMapElts root_map)
1973
1974 loop :: GhcMonad m =>
1975 [(Located ModuleName,IsBootInterface)]
1976 -- Work list: process these modules
1977 -> NodeMap [ModSummary]
1978 -- Visited set; the range is a list because
1979 -- the roots can have the same module names
1980 -- if allow_dup_roots is True
1981 -> m [ModSummary]
1982 -- The result includes the worklist, except
1983 -- for those mentioned in the visited set
1984 loop [] done = return (concat (nodeMapElts done))
1985 loop ((wanted_mod, is_boot) : ss) done
1986 | Just summs <- lookupFM done key
1987 = if isSingleton summs then
1988 loop ss done
1989 else
1990 do { liftIO $ multiRootsErr summs; return [] }
1991 | otherwise
1992 = do mb_s <- summariseModule hsc_env old_summary_map
1993 is_boot wanted_mod True
1994 Nothing excl_mods
1995 case mb_s of
1996 Nothing -> loop ss done
1997 Just s -> loop (msDeps s ++ ss) (addToFM done key [s])
1998 where
1999 key = (unLoc wanted_mod, if is_boot then HsBootFile else HsSrcFile)
2000
2001 mkRootMap :: [ModSummary] -> NodeMap [ModSummary]
2002 mkRootMap summaries = addListToFM_C (++) emptyFM
2003 [ (msKey s, [s]) | s <- summaries ]
2004
2005 msDeps :: ModSummary -> [(Located ModuleName, IsBootInterface)]
2006 -- (msDeps s) returns the dependencies of the ModSummary s.
2007 -- A wrinkle is that for a {-# SOURCE #-} import we return
2008 -- *both* the hs-boot file
2009 -- *and* the source file
2010 -- as "dependencies". That ensures that the list of all relevant
2011 -- modules always contains B.hs if it contains B.hs-boot.
2012 -- Remember, this pass isn't doing the topological sort. It's
2013 -- just gathering the list of all relevant ModSummaries
2014 msDeps s =
2015 concat [ [(m,True), (m,False)] | m <- ms_home_srcimps s ]
2016 ++ [ (m,False) | m <- ms_home_imps s ]
2017
2018 home_imps :: [Located (ImportDecl RdrName)] -> [Located ModuleName]
2019 home_imps imps = [ ideclName i | L _ i <- imps, isLocal (ideclPkgQual i) ]
2020 where isLocal Nothing = True
2021 isLocal (Just pkg) | pkg == fsLit "this" = True -- "this" is special
2022 isLocal _ = False
2023
2024 ms_home_allimps :: ModSummary -> [ModuleName]
2025 ms_home_allimps ms = map unLoc (ms_home_srcimps ms ++ ms_home_imps ms)
2026
2027 ms_home_srcimps :: ModSummary -> [Located ModuleName]
2028 ms_home_srcimps = home_imps . ms_srcimps
2029
2030 ms_home_imps :: ModSummary -> [Located ModuleName]
2031 ms_home_imps = home_imps . ms_imps
2032
2033 -----------------------------------------------------------------------------
2034 -- Summarising modules
2035
2036 -- We have two types of summarisation:
2037 --
2038 -- * Summarise a file. This is used for the root module(s) passed to
2039 -- cmLoadModules. The file is read, and used to determine the root
2040 -- module name. The module name may differ from the filename.
2041 --
2042 -- * Summarise a module. We are given a module name, and must provide
2043 -- a summary. The finder is used to locate the file in which the module
2044 -- resides.
2045
2046 summariseFile
2047 :: GhcMonad m =>
2048 HscEnv
2049 -> [ModSummary] -- old summaries
2050 -> FilePath -- source file name
2051 -> Maybe Phase -- start phase
2052 -> Bool -- object code allowed?
2053 -> Maybe (StringBuffer,ClockTime)
2054 -> m ModSummary
2055
2056 summariseFile hsc_env old_summaries file mb_phase obj_allowed maybe_buf
2057 -- we can use a cached summary if one is available and the
2058 -- source file hasn't changed, But we have to look up the summary
2059 -- by source file, rather than module name as we do in summarise.
2060 | Just old_summary <- findSummaryBySourceFile old_summaries file
2061 = do
2062 let location = ms_location old_summary
2063
2064 -- return the cached summary if the source didn't change
2065 src_timestamp <- case maybe_buf of
2066 Just (_,t) -> return t
2067 Nothing -> liftIO $ getModificationTime file
2068 -- The file exists; we checked in getRootSummary above.
2069 -- If it gets removed subsequently, then this
2070 -- getModificationTime may fail, but that's the right
2071 -- behaviour.
2072
2073 if ms_hs_date old_summary == src_timestamp
2074 then do -- update the object-file timestamp
2075 obj_timestamp <-
2076 if isObjectTarget (hscTarget (hsc_dflags hsc_env))
2077 || obj_allowed -- bug #1205
2078 then liftIO $ getObjTimestamp location False
2079 else return Nothing
2080 return old_summary{ ms_obj_date = obj_timestamp }
2081 else
2082 new_summary
2083
2084 | otherwise
2085 = new_summary
2086 where
2087 new_summary = do
2088 let dflags = hsc_dflags hsc_env
2089
2090 (dflags', hspp_fn, buf)
2091 <- preprocessFile hsc_env file mb_phase maybe_buf
2092
2093 (srcimps,the_imps, L _ mod_name) <- getImports dflags' buf hspp_fn file
2094
2095 -- Make a ModLocation for this file
2096 location <- liftIO $ mkHomeModLocation dflags mod_name file
2097
2098 -- Tell the Finder cache where it is, so that subsequent calls
2099 -- to findModule will find it, even if it's not on any search path
2100 mod <- liftIO $ addHomeModuleToFinder hsc_env mod_name location
2101
2102 src_timestamp <- case maybe_buf of
2103 Just (_,t) -> return t
2104 Nothing -> liftIO $ getModificationTime file
2105 -- getMofificationTime may fail
2106
2107 -- when the user asks to load a source file by name, we only
2108 -- use an object file if -fobject-code is on. See #1205.
2109 obj_timestamp <-
2110 if isObjectTarget (hscTarget (hsc_dflags hsc_env))
2111 || obj_allowed -- bug #1205
2112 then liftIO $ modificationTimeIfExists (ml_obj_file location)
2113 else return Nothing
2114
2115 return (ModSummary { ms_mod = mod, ms_hsc_src = HsSrcFile,
2116 ms_location = location,
2117 ms_hspp_file = hspp_fn,
2118 ms_hspp_opts = dflags',
2119 ms_hspp_buf = Just buf,
2120 ms_srcimps = srcimps, ms_imps = the_imps,
2121 ms_hs_date = src_timestamp,
2122 ms_obj_date = obj_timestamp })
2123
2124 findSummaryBySourceFile :: [ModSummary] -> FilePath -> Maybe ModSummary
2125 findSummaryBySourceFile summaries file
2126 = case [ ms | ms <- summaries, HsSrcFile <- [ms_hsc_src ms],
2127 expectJust "findSummaryBySourceFile" (ml_hs_file (ms_location ms)) == file ] of
2128 [] -> Nothing
2129 (x:_) -> Just x
2130
2131 -- Summarise a module, and pick up source and timestamp.
2132 summariseModule
2133 :: GhcMonad m =>
2134 HscEnv
2135 -> NodeMap ModSummary -- Map of old summaries
2136 -> IsBootInterface -- True <=> a {-# SOURCE #-} import
2137 -> Located ModuleName -- Imported module to be summarised
2138 -> Bool -- object code allowed?
2139 -> Maybe (StringBuffer, ClockTime)
2140 -> [ModuleName] -- Modules to exclude
2141 -> m (Maybe ModSummary) -- Its new summary
2142
2143 summariseModule hsc_env old_summary_map is_boot (L loc wanted_mod)
2144 obj_allowed maybe_buf excl_mods
2145 | wanted_mod `elem` excl_mods
2146 = return Nothing
2147
2148 | Just old_summary <- lookupFM old_summary_map (wanted_mod, hsc_src)
2149 = do -- Find its new timestamp; all the
2150 -- ModSummaries in the old map have valid ml_hs_files
2151 let location = ms_location old_summary
2152 src_fn = expectJust "summariseModule" (ml_hs_file location)
2153
2154 -- check the modification time on the source file, and
2155 -- return the cached summary if it hasn't changed. If the
2156 -- file has disappeared, we need to call the Finder again.
2157 case maybe_buf of
2158 Just (_,t) -> check_timestamp old_summary location src_fn t
2159 Nothing -> do
2160 m <- liftIO $ System.IO.Error.try (getModificationTime src_fn)
2161 case m of
2162 Right t -> check_timestamp old_summary location src_fn t
2163 Left e | isDoesNotExistError e -> find_it
2164 | otherwise -> liftIO $ ioError e
2165
2166 | otherwise = find_it
2167 where
2168 dflags = hsc_dflags hsc_env
2169
2170 hsc_src = if is_boot then HsBootFile else HsSrcFile
2171
2172 check_timestamp old_summary location src_fn src_timestamp
2173 | ms_hs_date old_summary == src_timestamp = do
2174 -- update the object-file timestamp
2175 obj_timestamp <- liftIO $
2176 if isObjectTarget (hscTarget (hsc_dflags hsc_env))
2177 || obj_allowed -- bug #1205
2178 then getObjTimestamp location is_boot
2179 else return Nothing
2180 return (Just old_summary{ ms_obj_date = obj_timestamp })
2181 | otherwise =
2182 -- source changed: re-summarise.
2183 new_summary location (ms_mod old_summary) src_fn src_timestamp
2184
2185 find_it = do
2186 -- Don't use the Finder's cache this time. If the module was
2187 -- previously a package module, it may have now appeared on the
2188 -- search path, so we want to consider it to be a home module. If
2189 -- the module was previously a home module, it may have moved.
2190 liftIO $ uncacheModule hsc_env wanted_mod
2191 found <- liftIO $ findImportedModule hsc_env wanted_mod Nothing
2192 case found of
2193 Found location mod
2194 | isJust (ml_hs_file location) ->
2195 -- Home package
2196 just_found location mod
2197 | otherwise ->
2198 -- Drop external-pkg
2199 ASSERT(modulePackageId mod /= thisPackage dflags)
2200 return Nothing
2201
2202 err -> liftIO $ noModError dflags loc wanted_mod err
2203 -- Not found
2204
2205 just_found location mod = do
2206 -- Adjust location to point to the hs-boot source file,
2207 -- hi file, object file, when is_boot says so
2208 let location' | is_boot = addBootSuffixLocn location
2209 | otherwise = location
2210 src_fn = expectJust "summarise2" (ml_hs_file location')
2211
2212 -- Check that it exists
2213 -- It might have been deleted since the Finder last found it
2214 maybe_t <- liftIO $ modificationTimeIfExists src_fn
2215 case maybe_t of
2216 Nothing -> noHsFileErr loc src_fn
2217 Just t -> new_summary location' mod src_fn t
2218
2219
2220 new_summary location mod src_fn src_timestamp
2221 = do
2222 -- Preprocess the source file and get its imports
2223 -- The dflags' contains the OPTIONS pragmas
2224 (dflags', hspp_fn, buf) <- preprocessFile hsc_env src_fn Nothing maybe_buf
2225 (srcimps, the_imps, L mod_loc mod_name) <- getImports dflags' buf hspp_fn src_fn
2226
2227 when (mod_name /= wanted_mod) $
2228 throwOneError $ mkPlainErrMsg mod_loc $
2229 text "File name does not match module name:"
2230 $$ text "Saw:" <+> quotes (ppr mod_name)
2231 $$ text "Expected:" <+> quotes (ppr wanted_mod)
2232
2233 -- Find the object timestamp, and return the summary
2234 obj_timestamp <- liftIO $
2235 if isObjectTarget (hscTarget (hsc_dflags hsc_env))
2236 || obj_allowed -- bug #1205
2237 then getObjTimestamp location is_boot
2238 else return Nothing
2239
2240 return (Just (ModSummary { ms_mod = mod,
2241 ms_hsc_src = hsc_src,
2242 ms_location = location,
2243 ms_hspp_file = hspp_fn,
2244 ms_hspp_opts = dflags',
2245 ms_hspp_buf = Just buf,
2246 ms_srcimps = srcimps,
2247 ms_imps = the_imps,
2248 ms_hs_date = src_timestamp,
2249 ms_obj_date = obj_timestamp }))
2250
2251
2252 getObjTimestamp :: ModLocation -> Bool -> IO (Maybe ClockTime)
2253 getObjTimestamp location is_boot
2254 = if is_boot then return Nothing
2255 else modificationTimeIfExists (ml_obj_file location)
2256
2257
2258 preprocessFile :: GhcMonad m =>
2259 HscEnv
2260 -> FilePath
2261 -> Maybe Phase -- ^ Starting phase
2262 -> Maybe (StringBuffer,ClockTime)
2263 -> m (DynFlags, FilePath, StringBuffer)
2264 preprocessFile hsc_env src_fn mb_phase Nothing
2265 = do
2266 (dflags', hspp_fn) <- preprocess hsc_env (src_fn, mb_phase)
2267 buf <- liftIO $ hGetStringBuffer hspp_fn
2268 return (dflags', hspp_fn, buf)
2269
2270 preprocessFile hsc_env src_fn mb_phase (Just (buf, _time))
2271 = do
2272 let dflags = hsc_dflags hsc_env
2273 -- case we bypass the preprocessing stage?
2274 let
2275 local_opts = getOptions dflags buf src_fn
2276 --
2277 (dflags', leftovers, warns)
2278 <- parseDynamicNoPackageFlags dflags local_opts
2279 checkProcessArgsResult leftovers
2280 handleFlagWarnings dflags' warns
2281
2282 let
2283 needs_preprocessing
2284 | Just (Unlit _) <- mb_phase = True
2285 | Nothing <- mb_phase, Unlit _ <- startPhase src_fn = True
2286 -- note: local_opts is only required if there's no Unlit phase
2287 | dopt Opt_Cpp dflags' = True
2288 | dopt Opt_Pp dflags' = True
2289 | otherwise = False
2290
2291 when needs_preprocessing $
2292 ghcError (ProgramError "buffer needs preprocesing; interactive check disabled")
2293
2294 return (dflags', src_fn, buf)
2295
2296
2297 -----------------------------------------------------------------------------
2298 -- Error messages
2299 -----------------------------------------------------------------------------
2300
2301 noModError :: DynFlags -> SrcSpan -> ModuleName -> FindResult -> IO ab
2302 -- ToDo: we don't have a proper line number for this error
2303 noModError dflags loc wanted_mod err
2304 = throwOneError $ mkPlainErrMsg loc $ cannotFindModule dflags wanted_mod err
2305
2306 noHsFileErr :: GhcMonad m => SrcSpan -> String -> m a
2307 noHsFileErr loc path
2308 = throwOneError $ mkPlainErrMsg loc $ text "Can't find" <+> text path
2309
2310 packageModErr :: GhcMonad m => ModuleName -> m a
2311 packageModErr mod
2312 = throwOneError $ mkPlainErrMsg noSrcSpan $
2313 text "module" <+> quotes (ppr mod) <+> text "is a package module"
2314
2315 multiRootsErr :: [ModSummary] -> IO ()
2316 multiRootsErr [] = panic "multiRootsErr"
2317 multiRootsErr summs@(summ1:_)
2318 = throwOneError $ mkPlainErrMsg noSrcSpan $
2319 text "module" <+> quotes (ppr mod) <+>
2320 text "is defined in multiple files:" <+>
2321 sep (map text files)
2322 where
2323 mod = ms_mod summ1
2324 files = map (expectJust "checkDup" . ml_hs_file . ms_location) summs
2325
2326 cyclicModuleErr :: [ModSummary] -> SDoc
2327 cyclicModuleErr ms
2328 = hang (ptext (sLit "Module imports form a cycle for modules:"))
2329 2 (vcat (map show_one ms))
2330 where
2331 mods_in_cycle = map ms_mod_name ms
2332 imp_modname = unLoc . ideclName . unLoc
2333 just_in_cycle = filter ((`elem` mods_in_cycle) . imp_modname)
2334
2335 show_one ms =
2336 vcat [ show_mod (ms_hsc_src ms) (ms_mod_name ms) <+>
2337 maybe empty (parens . text) (ml_hs_file (ms_location ms)),
2338 nest 2 $ ptext (sLit "imports:") <+> vcat [
2339 pp_imps HsBootFile (just_in_cycle $ ms_srcimps ms),
2340 pp_imps HsSrcFile (just_in_cycle $ ms_imps ms) ]
2341 ]
2342 show_mod hsc_src mod = ppr mod <> text (hscSourceString hsc_src)
2343 pp_imps src imps = fsep (map (show_mod src . unLoc . ideclName . unLoc) imps)
2344
2345
2346 -- | Inform GHC that the working directory has changed. GHC will flush
2347 -- its cache of module locations, since it may no longer be valid.
2348 --
2349 -- Note: Before changing the working directory make sure all threads running
2350 -- in the same session have stopped. If you change the working directory,
2351 -- you should also unload the current program (set targets to empty,
2352 -- followed by load).
2353 workingDirectoryChanged :: GhcMonad m => m ()
2354 workingDirectoryChanged = withSession $ (liftIO . flushFinderCaches)
2355
2356 -- -----------------------------------------------------------------------------
2357 -- inspecting the session
2358
2359 -- | Get the module dependency graph.
2360 getModuleGraph :: GhcMonad m => m ModuleGraph -- ToDo: DiGraph ModSummary
2361 getModuleGraph = liftM hsc_mod_graph getSession
2362
2363 -- | Determines whether a set of modules requires Template Haskell.
2364 --
2365 -- Note that if the session's 'DynFlags' enabled Template Haskell when
2366 -- 'depanal' was called, then each module in the returned module graph will
2367 -- have Template Haskell enabled whether it is actually needed or not.
2368 needsTemplateHaskell :: ModuleGraph -> Bool
2369 needsTemplateHaskell ms =
2370 any (dopt Opt_TemplateHaskell . ms_hspp_opts) ms
2371
2372 -- | Return @True@ <==> module is loaded.
2373 isLoaded :: GhcMonad m => ModuleName -> m Bool
2374 isLoaded m = withSession $ \hsc_env ->
2375 return $! isJust (lookupUFM (hsc_HPT hsc_env) m)
2376
2377 -- | Return the bindings for the current interactive session.
2378 getBindings :: GhcMonad m => m [TyThing]
2379 getBindings = withSession $ \hsc_env ->
2380 -- we have to implement the shadowing behaviour of ic_tmp_ids here
2381 -- (see InteractiveContext) and the quickest way is to use an OccEnv.
2382 let
2383 occ_env = mkOccEnv [ (nameOccName (idName id), AnId id)
2384 | id <- ic_tmp_ids (hsc_IC hsc_env) ]
2385 in
2386 return (occEnvElts occ_env)
2387
2388 getPrintUnqual :: GhcMonad m => m PrintUnqualified
2389 getPrintUnqual = withSession $ \hsc_env ->
2390 return (icPrintUnqual (hsc_dflags hsc_env) (hsc_IC hsc_env))
2391
2392 -- | Container for information about a 'Module'.
2393 data ModuleInfo = ModuleInfo {
2394 minf_type_env :: TypeEnv,
2395 minf_exports :: NameSet, -- ToDo, [AvailInfo] like ModDetails?
2396 minf_rdr_env :: Maybe GlobalRdrEnv, -- Nothing for a compiled/package mod
2397 minf_instances :: [Instance]
2398 #ifdef GHCI
2399 ,minf_modBreaks :: ModBreaks
2400 #endif
2401 -- ToDo: this should really contain the ModIface too
2402 }
2403 -- We don't want HomeModInfo here, because a ModuleInfo applies
2404 -- to package modules too.
2405
2406 -- | Request information about a loaded 'Module'
2407 getModuleInfo :: GhcMonad m => Module -> m (Maybe ModuleInfo) -- XXX: Maybe X
2408 getModuleInfo mdl = withSession $ \hsc_env -> do
2409 let mg = hsc_mod_graph hsc_env
2410 if mdl `elem` map ms_mod mg
2411 then liftIO $ getHomeModuleInfo hsc_env (moduleName mdl)
2412 else do
2413 {- if isHomeModule (hsc_dflags hsc_env) mdl
2414 then return Nothing
2415 else -} liftIO $ getPackageModuleInfo hsc_env mdl
2416 -- getPackageModuleInfo will attempt to find the interface, so
2417 -- we don't want to call it for a home module, just in case there
2418 -- was a problem loading the module and the interface doesn't
2419 -- exist... hence the isHomeModule test here. (ToDo: reinstate)
2420
2421 getPackageModuleInfo :: HscEnv -> Module -> IO (Maybe ModuleInfo)
2422 #ifdef GHCI
2423 getPackageModuleInfo hsc_env mdl = do
2424 (_msgs, mb_avails) <- getModuleExports hsc_env mdl
2425 case mb_avails of
2426 Nothing -> return Nothing
2427 Just avails -> do
2428 eps <- readIORef (hsc_EPS hsc_env)
2429 let
2430 names = availsToNameSet avails
2431 pte = eps_PTE eps
2432 tys = [ ty | name <- concatMap availNames avails,
2433 Just ty <- [lookupTypeEnv pte name] ]
2434 --
2435 return (Just (ModuleInfo {
2436 minf_type_env = mkTypeEnv tys,
2437 minf_exports = names,
2438 minf_rdr_env = Just $! availsToGlobalRdrEnv (moduleName mdl) avails,
2439 minf_instances = error "getModuleInfo: instances for package module unimplemented",
2440 minf_modBreaks = emptyModBreaks
2441 }))
2442 #else
2443 getPackageModuleInfo _hsc_env _mdl = do
2444 -- bogusly different for non-GHCI (ToDo)
2445 return Nothing
2446 #endif
2447
2448 getHomeModuleInfo :: HscEnv -> ModuleName -> IO (Maybe ModuleInfo)
2449 getHomeModuleInfo hsc_env mdl =
2450 case lookupUFM (hsc_HPT hsc_env) mdl of
2451 Nothing -> return Nothing
2452 Just hmi -> do
2453 let details = hm_details hmi
2454 return (Just (ModuleInfo {
2455 minf_type_env = md_types details,
2456 minf_exports = availsToNameSet (md_exports details),
2457 minf_rdr_env = mi_globals $! hm_iface hmi,
2458 minf_instances = md_insts details
2459 #ifdef GHCI
2460 ,minf_modBreaks = getModBreaks hmi
2461 #endif
2462 }))
2463
2464 -- | The list of top-level entities defined in a module
2465 modInfoTyThings :: ModuleInfo -> [TyThing]
2466 modInfoTyThings minf = typeEnvElts (minf_type_env minf)
2467
2468 modInfoTopLevelScope :: ModuleInfo -> Maybe [Name]
2469 modInfoTopLevelScope minf
2470 = fmap (map gre_name . globalRdrEnvElts) (minf_rdr_env minf)
2471
2472 modInfoExports :: ModuleInfo -> [Name]
2473 modInfoExports minf = nameSetToList $! minf_exports minf
2474
2475 -- | Returns the instances defined by the specified module.
2476 -- Warning: currently unimplemented for package modules.
2477 modInfoInstances :: ModuleInfo -> [Instance]
2478 modInfoInstances = minf_instances
2479
2480 modInfoIsExportedName :: ModuleInfo -> Name -> Bool
2481 modInfoIsExportedName minf name = elemNameSet name (minf_exports minf)
2482
2483 mkPrintUnqualifiedForModule :: GhcMonad m =>
2484 ModuleInfo
2485 -> m (Maybe PrintUnqualified) -- XXX: returns a Maybe X
2486 mkPrintUnqualifiedForModule minf = withSession $ \hsc_env -> do
2487 return (fmap (mkPrintUnqualified (hsc_dflags hsc_env)) (minf_rdr_env minf))
2488
2489 modInfoLookupName :: GhcMonad m =>
2490 ModuleInfo -> Name
2491 -> m (Maybe TyThing) -- XXX: returns a Maybe X
2492 modInfoLookupName minf name = withSession $ \hsc_env -> do
2493 case lookupTypeEnv (minf_type_env minf) name of
2494 Just tyThing -> return (Just tyThing)
2495 Nothing -> do
2496 eps <- liftIO $ readIORef (hsc_EPS hsc_env)
2497 return $! lookupType (hsc_dflags hsc_env)
2498 (hsc_HPT hsc_env) (eps_PTE eps) name
2499
2500 #ifdef GHCI
2501 modInfoModBreaks :: ModuleInfo -> ModBreaks
2502 modInfoModBreaks = minf_modBreaks
2503 #endif
2504
2505 isDictonaryId :: Id -> Bool
2506 isDictonaryId id
2507 = case tcSplitSigmaTy (idType id) of { (_tvs, _theta, tau) -> isDictTy tau }
2508
2509 -- | Looks up a global name: that is, any top-level name in any
2510 -- visible module. Unlike 'lookupName', lookupGlobalName does not use
2511 -- the interactive context, and therefore does not require a preceding
2512 -- 'setContext'.
2513 lookupGlobalName :: GhcMonad m => Name -> m (Maybe TyThing)
2514 lookupGlobalName name = withSession $ \hsc_env -> do
2515 liftIO $ lookupTypeHscEnv hsc_env name
2516
2517 findGlobalAnns :: (GhcMonad m, Typeable a) => ([Word8] -> a) -> AnnTarget Name -> m [a]
2518 findGlobalAnns deserialize target = withSession $ \hsc_env -> do
2519 ann_env <- liftIO $ prepareAnnotations hsc_env Nothing
2520 return (findAnns deserialize ann_env target)
2521
2522 #ifdef GHCI
2523 -- | get the GlobalRdrEnv for a session
2524 getGRE :: GhcMonad m => m GlobalRdrEnv
2525 getGRE = withSession $ \hsc_env-> return $ ic_rn_gbl_env (hsc_IC hsc_env)
2526 #endif
2527
2528 -- -----------------------------------------------------------------------------
2529
2530 -- | Return all /external/ modules available in the package database.
2531 -- Modules from the current session (i.e., from the 'HomePackageTable') are
2532 -- not included.
2533 packageDbModules :: GhcMonad m =>
2534 Bool -- ^ Only consider exposed packages.
2535 -> m [Module]
2536 packageDbModules only_exposed = do
2537 dflags <- getSessionDynFlags
2538 let pkgs = eltsUFM (pkgIdMap (pkgState dflags))
2539 return $
2540 [ mkModule pid modname | p <- pkgs
2541 , not only_exposed || exposed p
2542 , let pid = packageConfigId p
2543 , modname <- exposedModules p ]
2544
2545 -- -----------------------------------------------------------------------------
2546 -- Misc exported utils
2547
2548 dataConType :: DataCon -> Type
2549 dataConType dc = idType (dataConWrapId dc)
2550
2551 -- | print a 'NamedThing', adding parentheses if the name is an operator.
2552 pprParenSymName :: NamedThing a => a -> SDoc
2553 pprParenSymName a = parenSymOcc (getOccName a) (ppr (getName a))
2554
2555 -- ----------------------------------------------------------------------------
2556
2557 #if 0
2558
2559 -- ToDo:
2560 -- - Data and Typeable instances for HsSyn.
2561
2562 -- ToDo: check for small transformations that happen to the syntax in
2563 -- the typechecker (eg. -e ==> negate e, perhaps for fromIntegral)
2564
2565 -- ToDo: maybe use TH syntax instead of IfaceSyn? There's already a way
2566 -- to get from TyCons, Ids etc. to TH syntax (reify).
2567
2568 -- :browse will use either lm_toplev or inspect lm_interface, depending
2569 -- on whether the module is interpreted or not.
2570
2571 #endif
2572
2573 -- Extract the filename, stringbuffer content and dynflags associed to a module
2574 --
2575 -- XXX: Explain pre-conditions
2576 getModuleSourceAndFlags :: GhcMonad m => Module -> m (String, StringBuffer, DynFlags)
2577 getModuleSourceAndFlags mod = do
2578 m <- getModSummary (moduleName mod)
2579 case ml_hs_file $ ms_location m of
2580 Nothing -> throw $ mkApiErr (text "No source available for module " <+> ppr mod)
2581 Just sourceFile -> do
2582 source <- liftIO $ hGetStringBuffer sourceFile
2583 return (sourceFile, source, ms_hspp_opts m)
2584
2585
2586 -- | Return module source as token stream, including comments.
2587 --
2588 -- The module must be in the module graph and its source must be available.
2589 -- Throws a 'HscTypes.SourceError' on parse error.
2590 getTokenStream :: GhcMonad m => Module -> m [Located Token]
2591 getTokenStream mod = do
2592 (sourceFile, source, flags) <- getModuleSourceAndFlags mod
2593 let startLoc = mkSrcLoc (mkFastString sourceFile) 1 1
2594 case lexTokenStream source startLoc flags of
2595 POk _ ts -> return ts
2596 PFailed span err -> throw $ mkSrcErr (unitBag $ mkPlainErrMsg span err)
2597
2598 -- | Give even more information on the source than 'getTokenStream'
2599 -- This function allows reconstructing the source completely with
2600 -- 'showRichTokenStream'.
2601 getRichTokenStream :: GhcMonad m => Module -> m [(Located Token, String)]
2602 getRichTokenStream mod = do
2603 (sourceFile, source, flags) <- getModuleSourceAndFlags mod
2604 let startLoc = mkSrcLoc (mkFastString sourceFile) 1 1
2605 case lexTokenStream source startLoc flags of
2606 POk _ ts -> return $ addSourceToTokens startLoc source ts
2607 PFailed span err -> throw $ mkSrcErr (unitBag $ mkPlainErrMsg span err)
2608
2609 -- | Given a source location and a StringBuffer corresponding to this
2610 -- location, return a rich token stream with the source associated to the
2611 -- tokens.
2612 addSourceToTokens :: SrcLoc -> StringBuffer -> [Located Token]
2613 -> [(Located Token, String)]
2614 addSourceToTokens _ _ [] = []
2615 addSourceToTokens loc buf (t@(L span _) : ts)
2616 | not (isGoodSrcSpan span) = (t,"") : addSourceToTokens loc buf ts
2617 | otherwise = (t,str) : addSourceToTokens newLoc newBuf ts
2618 where
2619 (newLoc, newBuf, str) = go "" loc buf
2620 start = srcSpanStart span
2621 end = srcSpanEnd span
2622 go acc loc buf | loc < start = go acc nLoc nBuf
2623 | start <= loc && loc < end = go (ch:acc) nLoc nBuf
2624 | otherwise = (loc, buf, reverse acc)
2625 where (ch, nBuf) = nextChar buf
2626 nLoc = advanceSrcLoc loc ch
2627
2628
2629 -- | Take a rich token stream such as produced from 'getRichTokenStream' and
2630 -- return source code almost identical to the original code (except for
2631 -- insignificant whitespace.)
2632 showRichTokenStream :: [(Located Token, String)] -> String
2633 showRichTokenStream ts = go startLoc ts ""
2634 where sourceFile = srcSpanFile (getLoc . fst . head $ ts)
2635 startLoc = mkSrcLoc sourceFile 1 1
2636 go _ [] = id
2637 go loc ((L span _, str):ts)
2638 | not (isGoodSrcSpan span) = go loc ts
2639 | locLine == tokLine = ((replicate (tokCol - locCol) ' ') ++)
2640 . (str ++)
2641 . go tokEnd ts
2642 | otherwise = ((replicate (tokLine - locLine) '\n') ++)
2643 . ((replicate tokCol ' ') ++)
2644 . (str ++)
2645 . go tokEnd ts
2646 where (locLine, locCol) = (srcLocLine loc, srcLocCol loc)
2647 (tokLine, tokCol) = (srcSpanStartLine span, srcSpanStartCol span)
2648 tokEnd = srcSpanEnd span
2649
2650 -- -----------------------------------------------------------------------------
2651 -- Interactive evaluation
2652
2653 -- | Takes a 'ModuleName' and possibly a 'PackageId', and consults the
2654 -- filesystem and package database to find the corresponding 'Module',
2655 -- using the algorithm that is used for an @import@ declaration.
2656 findModule :: GhcMonad m => ModuleName -> Maybe FastString -> m Module
2657 findModule mod_name maybe_pkg = withSession $ \hsc_env -> do
2658 let
2659 dflags = hsc_dflags hsc_env
2660 this_pkg = thisPackage dflags
2661 --
2662 case maybe_pkg of
2663 Just pkg | fsToPackageId pkg /= this_pkg && pkg /= fsLit "this" -> liftIO $ do
2664 res <- findImportedModule hsc_env mod_name maybe_pkg
2665 case res of
2666 Found _ m -> return m
2667 err -> noModError dflags noSrcSpan mod_name err
2668 _otherwise -> do
2669 home <- lookupLoadedHomeModule mod_name
2670 case home of
2671 Just m -> return m
2672 Nothing -> liftIO $ do
2673 res <- findImportedModule hsc_env mod_name maybe_pkg
2674 case res of
2675 Found loc m | modulePackageId m /= this_pkg -> return m
2676 | otherwise -> modNotLoadedError m loc
2677 err -> noModError dflags noSrcSpan mod_name err
2678
2679 modNotLoadedError :: Module -> ModLocation -> IO a
2680 modNotLoadedError m loc = ghcError $ CmdLineError $ showSDoc $
2681 text "module is not loaded:" <+>
2682 quotes (ppr (moduleName m)) <+>
2683 parens (text (expectJust "modNotLoadedError" (ml_hs_file loc)))
2684
2685 -- | Like 'findModule', but differs slightly when the module refers to
2686 -- a source file, and the file has not been loaded via 'load'. In
2687 -- this case, 'findModule' will throw an error (module not loaded),
2688 -- but 'lookupModule' will check to see whether the module can also be
2689 -- found in a package, and if so, that package 'Module' will be
2690 -- returned. If not, the usual module-not-found error will be thrown.
2691 --
2692 lookupModule :: GhcMonad m => ModuleName -> Maybe FastString -> m Module
2693 lookupModule mod_name (Just pkg) = findModule mod_name (Just pkg)
2694 lookupModule mod_name Nothing = withSession $ \hsc_env -> do
2695 home <- lookupLoadedHomeModule mod_name
2696 case home of
2697 Just m -> return m
2698 Nothing -> liftIO $ do
2699 res <- findExposedPackageModule hsc_env mod_name Nothing
2700 case res of
2701 Found _ m -> return m
2702 err -> noModError (hsc_dflags hsc_env) noSrcSpan mod_name err
2703
2704 lookupLoadedHomeModule :: GhcMonad m => ModuleName -> m (Maybe Module)
2705 lookupLoadedHomeModule mod_name = withSession $ \hsc_env ->
2706 case lookupUFM (hsc_HPT hsc_env) mod_name of
2707 Just mod_info -> return (Just (mi_module (hm_iface mod_info)))
2708 _not_a_home_module -> return Nothing
2709
2710 #ifdef GHCI
2711 getHistorySpan :: GhcMonad m => History -> m SrcSpan
2712 getHistorySpan h = withSession $ \hsc_env ->
2713 return$ InteractiveEval.getHistorySpan hsc_env h
2714
2715 obtainTermFromVal :: GhcMonad m => Int -> Bool -> Type -> a -> m Term
2716 obtainTermFromVal bound force ty a =
2717 withSession $ \hsc_env ->
2718 liftIO $ InteractiveEval.obtainTermFromVal hsc_env bound force ty a
2719
2720 obtainTermFromId :: GhcMonad m => Int -> Bool -> Id -> m Term
2721 obtainTermFromId bound force id =
2722 withSession $ \hsc_env ->
2723 liftIO $ InteractiveEval.obtainTermFromId hsc_env bound force id
2724
2725 #endif