2 % (c) The GRASP/AQUA Project, Glasgow University, 1993-1998
7 pprModIface, showIface, -- Print the iface in Foo.hi
9 mkUsageInfo, -- Construct the usage info for a module
11 mkIface, -- Build a ModIface from a ModGuts,
12 -- including computing version information
14 writeIfaceFile, -- Write the interface file
16 checkOldIface -- See if recompilation is required, by
17 -- comparing version information
21 -----------------------------------------------
22 MkIface.lhs deals with versioning
23 -----------------------------------------------
25 Here's the version-related info in an interface file
27 module Foo 8 -- module-version
28 3 -- export-list-version
30 Usages: -- Version info for what this compilation of Foo imported
31 Baz 3 -- Module version
32 [4] -- The export-list version if Foo depended on it
33 (g,2) -- Function and its version
34 (T,1) -- Type and its version
36 <version> f :: Int -> Int {- Unfolding: \x -> Wib.t[2] x -}
37 -- The [2] says that f's unfolding
38 -- mentions verison 2 of Wib.t
40 -----------------------------------------------
42 -----------------------------------------------
45 * In the mi_usages information in an interface, we record the
46 version number of each free variable of the module
48 * In mkIface, we compute the version number of each exported thing A.f
49 by comparing its A.f's info with its new info, and bumping its
50 version number if it differs. If A.f mentions B.g, and B.g's version
51 number has changed, then we count A.f as having changed too.
53 * In checkOldIface we compare the mi_usages for the module with
54 the actual version info for all each thing recorded in mi_usages
59 We count A.f as changing if its fixity changes
63 If a rule changes, we want to recompile any module that might be
64 affected by that rule. For non-orphan rules, this is relatively easy.
65 If module M defines f, and a rule for f, just arrange that the version
66 number for M.f changes if any of the rules for M.f change. Any module
67 that does not depend on M.f can't be affected by the rule-change
70 Orphan rules (ones whose 'head function' is not defined in M) are
71 harder. Here's what we do.
73 * We have a per-module orphan-rule version number which changes if
74 any orphan rule changes. (It's unaffected by non-orphan rules.)
76 * We record usage info for any orphan module 'below' this one,
77 giving the orphan-rule version number. We recompile if this
80 The net effect is that if an orphan rule changes, we recompile every
81 module above it. That's very conservative, but it's devilishly hard
82 to know what it might affect, so we just have to be conservative.
86 In an iface file we have
88 instance Eq a => Eq [a] = dfun29
91 We have a version number for dfun29, covering its unfolding
92 etc. Suppose we are compiling a module M that imports A only
93 indirectly. If typechecking M uses this instance decl, we record the
94 dependency on A.dfun29 as if it were a free variable of the module
95 (via the tcg_inst_usages accumulator). That means that A will appear
96 in M's usage list. If the shape of the instance declaration changes,
97 then so will dfun29's version, triggering a recompilation.
99 Adding an instance declaration, or changing an instance decl that is
100 not currently used, is more tricky. (This really only makes a
101 difference when we have overlapping instance decls, because then the
102 new instance decl might kick in to override the old one.) We handle
103 this in a very similar way that we handle rules above.
105 * For non-orphan instance decls, identify one locally-defined tycon/class
106 mentioned in the decl. Treat the instance decl as part of the defn of that
107 tycon/class, so that if the shape of the instance decl changes, so does the
108 tycon/class; that in turn will force recompilation of anything that uses
111 * For orphan instance decls, act the same way as for orphan rules.
112 Indeed, we use the same global orphan-rule version number.
116 mkUsageInfo figures out what the ``usage information'' for this
117 moudule is; that is, what it must record in its interface file as the
120 We produce a line for every module B below the module, A, currently being
123 to record the fact that A does import B indirectly. This is used to decide
124 to look to look for B.hi rather than B.hi-boot when compiling a module that
125 imports A. This line says that A imports B, but uses nothing in it.
126 So we'll get an early bale-out when compiling A if B's version changes.
128 The usage information records:
131 \item (a) anything reachable from its body code
132 \item (b) any module exported with a @module Foo@
133 \item (c) anything reachable from an exported item
136 Why (b)? Because if @Foo@ changes then this module's export list
137 will change, so we must recompile this module at least as far as
138 making a new interface file --- but in practice that means complete
141 Why (c)? Consider this:
143 module A( f, g ) where | module B( f ) where
144 import B( f ) | f = h 3
148 Here, @B.f@ isn't used in A. Should we nevertheless record @B.f@ in
149 @A@'s usages? Our idea is that we aren't going to touch A.hi if it is
150 *identical* to what it was before. If anything about @B.f@ changes
151 than anyone who imports @A@ should be recompiled in case they use
152 @B.f@ (they'll get an early exit if they don't). So, if anything
153 about @B.f@ changes we'd better make sure that something in A.hi
154 changes, and the convenient way to do that is to record the version
155 number @B.f@ in A.hi in the usage list. If B.f changes that'll force a
156 complete recompiation of A, which is overkill but it's the only way to
157 write a new, slightly different, A.hi.
159 But the example is tricker. Even if @B.f@ doesn't change at all,
160 @B.h@ may do so, and this change may not be reflected in @f@'s version
161 number. But with -O, a module that imports A must be recompiled if
162 @B.h@ changes! So A must record a dependency on @B.h@. So we treat
163 the occurrence of @B.f@ in the export list *just as if* it were in the
164 code of A, and thereby haul in all the stuff reachable from it.
166 *** Conclusion: if A mentions B.f in its export list,
167 behave just as if A mentioned B.f in its source code,
168 and slurp in B.f and all its transitive closure ***
170 [NB: If B was compiled with -O, but A isn't, we should really *still*
171 haul in all the unfoldings for B, in case the module that imports A *is*
172 compiled with -O. I think this is the case.]
176 #include "HsVersions.h"
179 import Packages ( isHomeModule, PackageIdH(..) )
180 import IfaceSyn ( IfaceDecl(..), IfaceClassOp(..), IfaceConDecl(..),
181 IfaceRule(..), IfaceInst(..), IfaceExtName(..),
182 eqIfDecl, eqIfRule, eqIfInst, IfaceEq(..), (&&&), bool,
183 eqMaybeBy, eqListBy, visibleIfConDecls,
184 tyThingToIfaceDecl, instanceToIfaceInst, coreRuleToIfaceRule )
185 import LoadIface ( readIface, loadInterface )
186 import BasicTypes ( Version, initialVersion, bumpVersion )
188 import TcRnTypes ( mkModDeps )
189 import HscTypes ( ModIface(..), ModDetails(..),
190 ModGuts(..), IfaceExport,
191 HscEnv(..), hscEPS, Dependencies(..), FixItem(..),
192 ModSummary(..), msHiFilePath,
193 mkIfaceDepCache, mkIfaceFixCache, mkIfaceVerCache,
195 GenAvailInfo(..), availName,
196 ExternalPackageState(..),
197 Usage(..), IsBootInterface,
198 Deprecs(..), IfaceDeprecs, Deprecations,
203 import DynFlags ( GhcMode(..), DynFlags(..), DynFlag(..), dopt )
204 import StaticFlags ( opt_HiVersion )
205 import Name ( Name, nameModule, nameOccName, nameParent,
206 isExternalName, isInternalName, nameParent_maybe, isWiredInName,
207 isImplicitName, NamedThing(..) )
210 import OccName ( OccName, OccEnv, mkOccEnv, lookupOccEnv, emptyOccEnv,
212 OccSet, emptyOccSet, elemOccSet, occSetElts,
213 extendOccSet, extendOccSetList,
214 isEmptyOccSet, intersectOccSet, intersectsOccSet,
216 import Module ( Module, moduleFS,
217 ModLocation(..), mkSysModuleFS, moduleUserString,
218 ModuleEnv, emptyModuleEnv, lookupModuleEnv,
222 import Util ( createDirectoryHierarchy, directoryOf )
223 import Util ( sortLe, seqList )
224 import Binary ( getBinFileWithDict )
225 import BinIface ( writeBinIface, v_IgnoreHiWay )
226 import Unique ( Unique, Uniquable(..) )
227 import ErrUtils ( dumpIfSet_dyn, showPass )
228 import Digraph ( stronglyConnComp, SCC(..) )
229 import SrcLoc ( SrcSpan )
233 import DATA_IOREF ( writeIORef )
234 import Monad ( when )
235 import List ( insert )
236 import Maybes ( orElse, mapCatMaybes, isNothing, isJust,
237 fromJust, expectJust, MaybeErr(..) )
242 %************************************************************************
244 \subsection{Completing an interface}
246 %************************************************************************
250 -> Maybe ModIface -- The old interface, if we have it
251 -> ModGuts -- Usages, deprecations, etc
252 -> ModDetails -- The trimmed, tidied interface
253 -> IO (ModIface, -- The new one, complete with decls and versions
254 Bool) -- True <=> there was an old Iface, and the new one
255 -- is identical, so no need to write it
257 mkIface hsc_env maybe_old_iface
258 (ModGuts{ mg_module = this_mod,
262 mg_rdr_env = rdr_env,
263 mg_fix_env = fix_env,
264 mg_deprecs = src_deprecs })
265 (ModDetails{ md_insts = insts,
268 md_exports = exports })
270 -- NB: notice that mkIface does not look at the bindings
271 -- only at the TypeEnv. The previous Tidy phase has
272 -- put exactly the info into the TypeEnv that we want
273 -- to expose in the interface
275 = do { eps <- hscEPS hsc_env
276 ; let { ext_nm_rhs = mkExtNameFn hsc_env eps this_mod
277 ; ext_nm_lhs = mkLhsNameFn this_mod
279 ; decls = [ tyThingToIfaceDecl ext_nm_rhs thing
280 | thing <- typeEnvElts type_env,
281 not (isImplicitName (getName thing)) ]
282 -- Don't put implicit Ids and class tycons in the interface file
284 ; fixities = [(occ,fix) | FixItem occ fix _ <- nameEnvElts fix_env]
285 ; deprecs = mkIfaceDeprec src_deprecs
286 ; iface_rules = map (coreRuleToIfaceRule ext_nm_lhs ext_nm_rhs) rules
287 ; iface_insts = map (instanceToIfaceInst ext_nm_lhs) insts
289 ; intermediate_iface = ModIface {
290 mi_module = this_mod,
291 mi_package = HomePackage,
295 mi_exports = mkIfaceExports exports,
296 mi_insts = sortLe le_inst iface_insts,
297 mi_rules = sortLe le_rule iface_rules,
298 mi_fixities = fixities,
299 mi_deprecs = deprecs,
300 mi_globals = Just rdr_env,
302 -- Left out deliberately: filled in by addVersionInfo
303 mi_mod_vers = initialVersion,
304 mi_exp_vers = initialVersion,
305 mi_rule_vers = initialVersion,
306 mi_orphan = False, -- Always set by addVersionInfo, but
307 -- it's a strict field, so we can't omit it.
308 mi_decls = deliberatelyOmitted "decls",
309 mi_ver_fn = deliberatelyOmitted "ver_fn",
311 -- And build the cached values
312 mi_dep_fn = mkIfaceDepCache deprecs,
313 mi_fix_fn = mkIfaceFixCache fixities }
315 -- Add version information
316 ; (new_iface, no_change_at_all, pp_diffs, pp_orphs)
317 = _scc_ "versioninfo"
318 addVersionInfo maybe_old_iface intermediate_iface decls
322 ; when (isJust pp_orphs && dopt Opt_WarnOrphans dflags)
323 (printDump (fromJust pp_orphs))
324 ; when (dopt Opt_D_dump_hi_diffs dflags) (printDump pp_diffs)
325 ; dumpIfSet_dyn dflags Opt_D_dump_hi "FINAL INTERFACE"
326 (pprModIface new_iface)
328 ; return (new_iface, no_change_at_all) }
330 r1 `le_rule` r2 = ifRuleName r1 <= ifRuleName r2
331 i1 `le_inst` i2 = ifDFun i1 <= ifDFun i2
333 dflags = hsc_dflags hsc_env
334 deliberatelyOmitted x = panic ("Deliberately omitted: " ++ x)
337 -----------------------------
338 writeIfaceFile :: HscEnv -> ModLocation -> ModIface -> Bool -> IO ()
339 -- Write the interface file, if necessary
340 writeIfaceFile hsc_env location new_iface no_change_at_all
341 | no_change_at_all = return ()
342 | ghc_mode == Interactive = return ()
343 | ghc_mode == JustTypecheck = return ()
345 = do { createDirectoryHierarchy (directoryOf hi_file_path)
346 ; writeBinIface hi_file_path new_iface }
348 ghc_mode = ghcMode (hsc_dflags hsc_env)
349 hi_file_path = ml_hi_file location
352 -----------------------------
353 mkExtNameFn :: HscEnv -> ExternalPackageState -> Module -> Name -> IfaceExtName
354 mkExtNameFn hsc_env eps this_mod
357 dflags = hsc_dflags hsc_env
358 hpt = hsc_HPT hsc_env
362 | mod == this_mod = case nameParent_maybe name of
363 Nothing -> LocalTop occ
364 Just par -> LocalTopSub occ (nameOccName par)
365 | isWiredInName name = ExtPkg mod occ
366 | isHomeModule dflags mod = HomePkg mod occ vers
367 | otherwise = ExtPkg mod occ
369 mod = nameModule name
370 occ = nameOccName name
371 par_occ = nameOccName (nameParent name)
372 -- The version of the *parent* is the one want
373 vers = lookupVersion mod par_occ
375 lookupVersion :: Module -> OccName -> Version
376 -- Even though we're looking up a home-package thing, in
377 -- one-shot mode the imported interfaces may be in the PIT
378 lookupVersion mod occ
379 = mi_ver_fn iface occ `orElse`
380 pprPanic "lookupVers1" (ppr mod <+> ppr occ)
382 iface = lookupIfaceByModule hpt pit mod `orElse`
383 pprPanic "lookupVers2" (ppr mod <+> ppr occ)
386 ---------------------
387 -- mkLhsNameFn ignores versioning info altogether
388 -- It is used for the LHS of instance decls and rules, where we
389 -- there's no point in recording version info
390 mkLhsNameFn :: Module -> Name -> IfaceExtName
391 mkLhsNameFn this_mod name
392 | isInternalName name = pprTrace "mkLhsNameFn: unexpected internal" (ppr name) $
393 LocalTop occ -- Should not happen
394 | mod == this_mod = LocalTop occ
395 | otherwise = ExtPkg mod occ
397 mod = nameModule name
398 occ = nameOccName name
401 -----------------------------
402 -- Compute version numbers for local decls
404 addVersionInfo :: Maybe ModIface -- The old interface, read from M.hi
405 -> ModIface -- The new interface decls (lacking decls)
406 -> [IfaceDecl] -- The new decls
408 Bool, -- True <=> no changes at all; no need to write new Iface
410 Maybe SDoc) -- Warnings about orphans
412 addVersionInfo Nothing new_iface new_decls
413 -- No old interface, so definitely write a new one!
414 = (new_iface { mi_orphan = anyNothing ifInstOrph (mi_insts new_iface)
415 || anyNothing ifRuleOrph (mi_rules new_iface),
416 mi_decls = [(initialVersion, decl) | decl <- new_decls],
417 mi_ver_fn = \n -> Just initialVersion },
419 ptext SLIT("No old interface file"),
420 pprOrphans orph_insts orph_rules)
422 orph_insts = filter (isNothing . ifInstOrph) (mi_insts new_iface)
423 orph_rules = filter (isNothing . ifRuleOrph) (mi_rules new_iface)
425 addVersionInfo (Just old_iface@(ModIface { mi_mod_vers = old_mod_vers,
426 mi_exp_vers = old_exp_vers,
427 mi_rule_vers = old_rule_vers,
428 mi_decls = old_decls,
429 mi_ver_fn = old_decl_vers,
430 mi_fix_fn = old_fixities }))
431 new_iface@(ModIface { mi_fix_fn = new_fixities })
434 | no_change_at_all = (old_iface, True, ptext SLIT("Interface file unchanged"), pp_orphs)
435 | otherwise = (final_iface, False, vcat [ptext SLIT("Interface file has changed"),
436 nest 2 pp_diffs], pp_orphs)
438 final_iface = new_iface { mi_mod_vers = bump_unless no_output_change old_mod_vers,
439 mi_exp_vers = bump_unless no_export_change old_exp_vers,
440 mi_rule_vers = bump_unless no_rule_change old_rule_vers,
441 mi_orphan = not (null new_orph_rules && null new_orph_insts),
442 mi_decls = decls_w_vers,
443 mi_ver_fn = mkIfaceVerCache decls_w_vers }
445 decls_w_vers = [(add_vers decl, decl) | decl <- new_decls]
448 (old_non_orph_insts, old_orph_insts) = mkOrphMap ifInstOrph (mi_insts old_iface)
449 (new_non_orph_insts, new_orph_insts) = mkOrphMap ifInstOrph (mi_insts new_iface)
450 same_insts occ = eqMaybeBy (eqListBy eqIfInst)
451 (lookupOccEnv old_non_orph_insts occ)
452 (lookupOccEnv new_non_orph_insts occ)
454 (old_non_orph_rules, old_orph_rules) = mkOrphMap ifRuleOrph (mi_rules old_iface)
455 (new_non_orph_rules, new_orph_rules) = mkOrphMap ifRuleOrph (mi_rules new_iface)
456 same_rules occ = eqMaybeBy (eqListBy eqIfRule)
457 (lookupOccEnv old_non_orph_rules occ)
458 (lookupOccEnv new_non_orph_rules occ)
460 -- Computing what changed
461 no_output_change = no_decl_change && no_rule_change &&
462 no_export_change && no_deprec_change
463 no_export_change = mi_exports new_iface == mi_exports old_iface -- Kept sorted
464 no_decl_change = isEmptyOccSet changed_occs
465 no_rule_change = not (changedWrt changed_occs (eqListBy eqIfRule old_orph_rules new_orph_rules)
466 || changedWrt changed_occs (eqListBy eqIfInst old_orph_insts new_orph_insts))
467 no_deprec_change = mi_deprecs new_iface == mi_deprecs old_iface
469 -- If the usages havn't changed either, we don't need to write the interface file
470 no_other_changes = mi_usages new_iface == mi_usages old_iface &&
471 mi_deps new_iface == mi_deps old_iface
472 no_change_at_all = no_output_change && no_other_changes
474 pp_diffs = vcat [pp_change no_export_change "Export list"
475 (ppr old_exp_vers <+> arrow <+> ppr (mi_exp_vers final_iface)),
476 pp_change no_rule_change "Rules"
477 (ppr old_rule_vers <+> arrow <+> ppr (mi_rule_vers final_iface)),
478 pp_change no_deprec_change "Deprecations" empty,
479 pp_change no_other_changes "Usages" empty,
481 pp_change True what info = empty
482 pp_change False what info = text what <+> ptext SLIT("changed") <+> info
485 old_decl_env = mkOccEnv [(ifName decl, decl) | (_,decl) <- old_decls]
486 same_fixity n = bool (old_fixities n == new_fixities n)
489 -- Adding version info
490 new_version = bumpVersion old_mod_vers
491 add_vers decl | occ `elemOccSet` changed_occs = new_version
492 | otherwise = expectJust "add_vers" (old_decl_vers occ)
493 -- If it's unchanged, there jolly well
494 where -- should be an old version number
498 changed_occs :: OccSet
499 changed_occs = computeChangedOccs eq_info
501 eq_info :: [(OccName, IfaceEq)]
502 eq_info = map check_eq new_decls
503 check_eq new_decl | Just old_decl <- lookupOccEnv old_decl_env occ
504 = (occ, new_decl `eqIfDecl` old_decl &&&
505 eq_indirects new_decl)
506 | otherwise {- No corresponding old decl -}
509 occ = ifName new_decl
511 eq_indirects :: IfaceDecl -> IfaceEq
512 -- When seeing if two decls are the same, remember to
513 -- check whether any relevant fixity or rules have changed
514 eq_indirects (IfaceId {ifName = occ}) = eq_ind_occ occ
515 eq_indirects (IfaceClass {ifName = cls_occ, ifSigs = sigs})
516 = same_insts cls_occ &&&
517 eq_ind_occs [op | IfaceClassOp op _ _ <- sigs]
518 eq_indirects (IfaceData {ifName = tc_occ, ifCons = cons})
519 = same_insts tc_occ &&& same_fixity tc_occ &&& -- The TyCon can have a fixity too
520 eq_ind_occs (map ifConOcc (visibleIfConDecls cons))
521 eq_indirects other = Equal -- Synonyms and foreign declarations
523 eq_ind_occ :: OccName -> IfaceEq -- For class ops and Ids; check fixity and rules
524 eq_ind_occ occ = same_fixity occ &&& same_rules occ
525 eq_ind_occs = foldr ((&&&) . eq_ind_occ) Equal
529 pp_decl_diffs :: SDoc -- Nothing => no changes
531 | isEmptyOccSet changed_occs = empty
533 = vcat [ptext SLIT("Changed occs:") <+> ppr (occSetElts changed_occs),
534 ptext SLIT("Version change for these decls:"),
535 nest 2 (vcat (map show_change new_decls))]
537 eq_env = mkOccEnv eq_info
539 | not (occ `elemOccSet` changed_occs) = empty
541 = vcat [ppr occ <+> ppr (old_decl_vers occ) <+> arrow <+> ppr new_version,
544 occ = ifName new_decl
545 why = case lookupOccEnv eq_env occ of
546 Just (EqBut occs) -> sep [ppr occ <> colon, ptext SLIT("Free vars (only) changed:"),
547 nest 2 (braces (fsep (map ppr (occSetElts
548 (occs `intersectOccSet` changed_occs)))))]
550 | Just old_decl <- lookupOccEnv old_decl_env occ
551 -> vcat [ptext SLIT("Old:") <+> ppr old_decl,
552 ptext SLIT("New:") <+> ppr new_decl]
554 -> ppr occ <+> ptext SLIT("only in new interface")
555 other -> pprPanic "MkIface.show_change" (ppr occ)
557 pp_orphs = pprOrphans new_orph_insts new_orph_rules
559 pprOrphans insts rules
560 | null insts && null rules = Nothing
563 if null insts then empty else
564 hang (ptext SLIT("Warning: orphan instances:"))
565 2 (vcat (map ppr insts)),
566 if null rules then empty else
567 hang (ptext SLIT("Warning: orphan rules:"))
568 2 (vcat (map ppr rules))
571 computeChangedOccs :: [(OccName, IfaceEq)] -> OccSet
572 computeChangedOccs eq_info
573 = foldl add_changes emptyOccSet (stronglyConnComp edges)
575 edges :: [((OccName,IfaceEq), Unique, [Unique])]
576 edges = [ (node, getUnique occ, map getUnique occs)
577 | node@(occ, iface_eq) <- eq_info
578 , let occs = case iface_eq of
579 EqBut occ_set -> occSetElts occ_set
582 -- Changes in declarations
583 add_changes :: OccSet -> SCC (OccName, IfaceEq) -> OccSet
584 add_changes so_far (AcyclicSCC (occ, iface_eq))
585 | changedWrt so_far iface_eq -- This one has changed
586 = extendOccSet so_far occ
587 add_changes so_far (CyclicSCC pairs)
588 | changedWrt so_far (foldr1 (&&&) (map snd pairs)) -- One of this group has changed
589 = extendOccSetList so_far (map fst pairs)
590 add_changes so_far other = so_far
592 changedWrt :: OccSet -> IfaceEq -> Bool
593 changedWrt so_far Equal = False
594 changedWrt so_far NotEqual = True
595 changedWrt so_far (EqBut kids) = so_far `intersectsOccSet` kids
597 ----------------------
598 -- mkOrphMap partitions instance decls or rules into
599 -- (a) an OccEnv for ones that are not orphans,
600 -- mapping the local OccName to a list of its decls
601 -- (b) a list of orphan decls
602 mkOrphMap :: (decl -> Maybe OccName) -- (Just occ) for a non-orphan decl, keyed by occ
603 -- Nothing for an orphan decl
604 -> [decl] -- Sorted into canonical order
605 -> (OccEnv [decl], -- Non-orphan decls associated with their key;
606 -- each sublist in canonical order
607 [decl]) -- Orphan decls; in canonical order
608 mkOrphMap get_key decls
609 = foldl go (emptyOccEnv, []) decls
611 go (non_orphs, orphs) d
612 | Just occ <- get_key d
613 = (extendOccEnv_C (\ ds _ -> d:ds) non_orphs occ [d], orphs)
614 | otherwise = (non_orphs, d:orphs)
616 anyNothing :: (a -> Maybe b) -> [a] -> Bool
617 anyNothing p [] = False
618 anyNothing p (x:xs) = isNothing (p x) || anyNothing p xs
620 ----------------------
621 mkIfaceDeprec :: Deprecations -> IfaceDeprecs
622 mkIfaceDeprec NoDeprecs = NoDeprecs
623 mkIfaceDeprec (DeprecAll t) = DeprecAll t
624 mkIfaceDeprec (DeprecSome env) = DeprecSome (sortLe (<=) (nameEnvElts env))
626 ----------------------
627 bump_unless :: Bool -> Version -> Version
628 bump_unless True v = v -- True <=> no change
629 bump_unless False v = bumpVersion v
633 %*********************************************************
635 \subsection{Keeping track of what we've slurped, and version numbers}
637 %*********************************************************
641 mkUsageInfo :: HscEnv
642 -> ModuleEnv (Module, Maybe Bool, SrcSpan)
643 -> [(Module, IsBootInterface)]
644 -> NameSet -> IO [Usage]
645 mkUsageInfo hsc_env dir_imp_mods dep_mods used_names
646 = do { eps <- hscEPS hsc_env
647 ; let usages = mk_usage_info (eps_PIT eps) hsc_env
648 dir_imp_mods dep_mods used_names
649 ; usages `seqList` return usages }
650 -- seq the list of Usages returned: occasionally these
651 -- don't get evaluated for a while and we can end up hanging on to
652 -- the entire collection of Ifaces.
654 mk_usage_info pit hsc_env dir_imp_mods dep_mods proto_used_names
655 = mapCatMaybes mkUsage dep_mods
656 -- ToDo: do we need to sort into canonical order?
658 dflags = hsc_dflags hsc_env
659 hpt = hsc_HPT hsc_env
661 used_names = mkNameSet $ -- Eliminate duplicates
662 [ nameParent n -- Just record usage on the 'main' names
663 | n <- nameSetToList proto_used_names
664 , not (isWiredInName n) -- Don't record usages for wired-in names
665 , isExternalName n -- Ignore internal names
668 -- ent_map groups together all the things imported and used
669 -- from a particular module in this package
670 ent_map :: ModuleEnv [OccName]
671 ent_map = foldNameSet add_mv emptyModuleEnv used_names
672 add_mv name mv_map = extendModuleEnv_C add_item mv_map mod [occ]
674 occ = nameOccName name
675 mod = nameModule name
676 add_item occs _ = occ:occs
678 import_all mod = case lookupModuleEnv dir_imp_mods mod of
679 Just (_,imp_all,_) -> isNothing imp_all
682 -- We want to create a Usage for a home module if
683 -- a) we used something from; has something in used_names
684 -- b) we imported all of it, even if we used nothing from it
685 -- (need to recompile if its export list changes: export_vers)
686 -- c) is a home-package orphan module (need to recompile if its
687 -- instance decls change: rules_vers)
688 mkUsage :: (Module, Bool) -> Maybe Usage
689 mkUsage (mod_name, _)
690 | isNothing maybe_iface -- We can't depend on it if we didn't
691 || not (isHomeModule dflags mod) -- even open the interface!
695 = Nothing -- Record no usage info
698 = Just (Usage { usg_name = mod,
700 usg_exports = export_vers,
701 usg_entities = ent_vers,
702 usg_rules = rules_vers })
704 maybe_iface = lookupIfaceByModule hpt pit mod_name
705 -- In one-shot mode, the interfaces for home-package
706 -- modules accumulate in the PIT not HPT. Sigh.
708 Just iface = maybe_iface
709 mod = mi_module iface
710 orphan_mod = mi_orphan iface
711 version_env = mi_ver_fn iface
712 mod_vers = mi_mod_vers iface
713 rules_vers = mi_rule_vers iface
714 all_imported = import_all mod
715 export_vers | all_imported = Just (mi_exp_vers iface)
716 | otherwise = Nothing
718 -- The sort is to put them into canonical order
719 used_occs = lookupModuleEnv ent_map mod `orElse` []
720 ent_vers :: [(OccName,Version)]
721 ent_vers = [ (occ, version_env occ `orElse` initialVersion)
722 | occ <- sortLe (<=) used_occs]
726 mkIfaceExports :: NameSet -> [(Module, [GenAvailInfo OccName])]
727 -- Group by module and sort by occurrence
728 -- This keeps the list in canonical order
729 mkIfaceExports exports
730 = [ (mkSysModuleFS fs, eltsFM avails)
731 | (fs, avails) <- fmToList groupFM
734 groupFM :: FiniteMap FastString (FiniteMap FastString (GenAvailInfo OccName))
735 -- Deliberately use the FastString so we
736 -- get a canonical ordering
737 groupFM = foldl add emptyFM (nameSetToList exports)
739 add env name = addToFM_C add_avail env mod_fs
740 (unitFM avail_fs avail)
742 occ = nameOccName name
743 mod_fs = moduleFS (nameModule name)
744 avail | Just p <- nameParent_maybe name = AvailTC (nameOccName p) [occ]
745 | isTcOcc occ = AvailTC occ [occ]
746 | otherwise = Avail occ
747 avail_fs = occNameFS (availName avail)
748 add_avail avail_fm _ = addToFM_C add_item avail_fm avail_fs avail
750 add_item (AvailTC p occs) _ = AvailTC p (List.insert occ occs)
751 add_item (Avail n) _ = pprPanic "MkIface.addAvail" (ppr n <+> ppr name)
755 %************************************************************************
757 Load the old interface file for this module (unless
758 we have it aleady), and check whether it is up to date
761 %************************************************************************
764 checkOldIface :: HscEnv
766 -> Bool -- Source unchanged
767 -> Maybe ModIface -- Old interface from compilation manager, if any
768 -> IO (RecompileRequired, Maybe ModIface)
770 checkOldIface hsc_env mod_summary source_unchanged maybe_iface
771 = do { showPass (hsc_dflags hsc_env)
772 ("Checking old interface for " ++ moduleUserString (ms_mod mod_summary)) ;
774 ; initIfaceCheck hsc_env $
775 check_old_iface mod_summary source_unchanged maybe_iface
778 check_old_iface mod_summary source_unchanged maybe_iface
779 = -- CHECK WHETHER THE SOURCE HAS CHANGED
780 ifM (not source_unchanged)
781 (traceHiDiffs (nest 4 (text "Source file changed or recompilation check turned off")))
784 -- If the source has changed and we're in interactive mode, avoid reading
785 -- an interface; just return the one we might have been supplied with.
786 getGhciMode `thenM` \ ghci_mode ->
787 if (ghci_mode == Interactive || ghci_mode == JustTypecheck)
788 && not source_unchanged then
789 returnM (outOfDate, maybe_iface)
792 case maybe_iface of {
793 Just old_iface -> -- Use the one we already have
794 checkVersions source_unchanged old_iface `thenM` \ recomp ->
795 returnM (recomp, Just old_iface)
799 -- Try and read the old interface for the current module
800 -- from the .hi file left from the last time we compiled it
802 iface_path = msHiFilePath mod_summary
804 readIface (ms_mod mod_summary) iface_path False `thenM` \ read_result ->
805 case read_result of {
806 Failed err -> -- Old interface file not found, or garbled; give up
807 traceIf (text "FYI: cannot read old interface file:"
808 $$ nest 4 err) `thenM_`
809 returnM (outOfDate, Nothing)
813 -- We have got the old iface; check its versions
814 checkVersions source_unchanged iface `thenM` \ recomp ->
815 returnM (recomp, Just iface)
819 @recompileRequired@ is called from the HscMain. It checks whether
820 a recompilation is required. It needs access to the persistent state,
821 finder, etc, because it may have to load lots of interface files to
822 check their versions.
825 type RecompileRequired = Bool
826 upToDate = False -- Recompile not required
827 outOfDate = True -- Recompile required
829 checkVersions :: Bool -- True <=> source unchanged
830 -> ModIface -- Old interface
831 -> IfG RecompileRequired
832 checkVersions source_unchanged iface
833 | not source_unchanged
836 = do { traceHiDiffs (text "Considering whether compilation is required for" <+>
837 ppr (mi_module iface) <> colon)
839 -- Source code unchanged and no errors yet... carry on
841 -- First put the dependent-module info, read from the old interface, into the envt,
842 -- so that when we look for interfaces we look for the right one (.hi or .hi-boot)
844 -- It's just temporary because either the usage check will succeed
845 -- (in which case we are done with this module) or it'll fail (in which
846 -- case we'll compile the module from scratch anyhow).
848 -- We do this regardless of compilation mode
849 ; updateEps_ $ \eps -> eps { eps_is_boot = mod_deps }
851 ; checkList [checkModUsage u | u <- mi_usages iface]
854 -- This is a bit of a hack really
855 mod_deps :: ModuleEnv (Module, IsBootInterface)
856 mod_deps = mkModDeps (dep_mods (mi_deps iface))
858 checkModUsage :: Usage -> IfG RecompileRequired
859 -- Given the usage information extracted from the old
860 -- M.hi file for the module being compiled, figure out
861 -- whether M needs to be recompiled.
863 checkModUsage (Usage { usg_name = mod_name, usg_mod = old_mod_vers,
864 usg_rules = old_rule_vers,
865 usg_exports = maybe_old_export_vers,
866 usg_entities = old_decl_vers })
867 = -- Load the imported interface is possible
869 doc_str = sep [ptext SLIT("need version info for"), ppr mod_name]
871 traceHiDiffs (text "Checking usages for module" <+> ppr mod_name) `thenM_`
873 loadInterface doc_str mod_name ImportBySystem `thenM` \ mb_iface ->
874 -- Load the interface, but don't complain on failure;
875 -- Instead, get an Either back which we can test
878 Failed exn -> (out_of_date (sep [ptext SLIT("Can't find version number for module"),
880 -- Couldn't find or parse a module mentioned in the
881 -- old interface file. Don't complain -- it might just be that
882 -- the current module doesn't need that import and it's been deleted
886 new_mod_vers = mi_mod_vers iface
887 new_decl_vers = mi_ver_fn iface
888 new_export_vers = mi_exp_vers iface
889 new_rule_vers = mi_rule_vers iface
892 checkModuleVersion old_mod_vers new_mod_vers `thenM` \ recompile ->
893 if not recompile then
898 if checkExportList maybe_old_export_vers new_export_vers then
899 out_of_date_vers (ptext SLIT(" Export list changed"))
900 (fromJust maybe_old_export_vers)
905 if old_rule_vers /= new_rule_vers then
906 out_of_date_vers (ptext SLIT(" Rules changed"))
907 old_rule_vers new_rule_vers
910 -- CHECK ITEMS ONE BY ONE
911 checkList [checkEntityUsage new_decl_vers u | u <- old_decl_vers] `thenM` \ recompile ->
913 returnM outOfDate -- This one failed, so just bail out now
915 up_to_date (ptext SLIT(" Great! The bits I use are up to date"))
918 ------------------------
919 checkModuleVersion old_mod_vers new_mod_vers
920 | new_mod_vers == old_mod_vers
921 = up_to_date (ptext SLIT("Module version unchanged"))
924 = out_of_date_vers (ptext SLIT(" Module version has changed"))
925 old_mod_vers new_mod_vers
927 ------------------------
928 checkExportList Nothing new_vers = upToDate
929 checkExportList (Just v) new_vers = v /= new_vers
931 ------------------------
932 checkEntityUsage new_vers (name,old_vers)
933 = case new_vers name of
935 Nothing -> -- We used it before, but it ain't there now
936 out_of_date (sep [ptext SLIT("No longer exported:"), ppr name])
938 Just new_vers -- It's there, but is it up to date?
939 | new_vers == old_vers -> traceHiDiffs (text " Up to date" <+> ppr name <+> parens (ppr new_vers)) `thenM_`
941 | otherwise -> out_of_date_vers (ptext SLIT(" Out of date:") <+> ppr name)
944 up_to_date msg = traceHiDiffs msg `thenM_` returnM upToDate
945 out_of_date msg = traceHiDiffs msg `thenM_` returnM outOfDate
946 out_of_date_vers msg old_vers new_vers
947 = out_of_date (hsep [msg, ppr old_vers, ptext SLIT("->"), ppr new_vers])
949 ----------------------
950 checkList :: [IfG RecompileRequired] -> IfG RecompileRequired
951 -- This helper is used in two places
952 checkList [] = returnM upToDate
953 checkList (check:checks) = check `thenM` \ recompile ->
960 %************************************************************************
964 %************************************************************************
967 showIface :: FilePath -> IO ()
968 -- Read binary interface, and print it out
969 showIface filename = do
970 -- skip the version check; we don't want to worry about profiled vs.
971 -- non-profiled interfaces, for example.
972 writeIORef v_IgnoreHiWay True
973 iface <- Binary.getBinFileWithDict filename
974 printDump (pprModIface iface)
980 pprModIface :: ModIface -> SDoc
983 = vcat [ ptext SLIT("interface")
984 <+> ppr_package (mi_package iface)
985 <+> ppr (mi_module iface) <+> pp_boot
986 <+> ppr (mi_mod_vers iface) <+> pp_sub_vers
987 <+> (if mi_orphan iface then ptext SLIT("[orphan module]") else empty)
988 <+> int opt_HiVersion
989 <+> ptext SLIT("where")
990 , vcat (map pprExport (mi_exports iface))
991 , pprDeps (mi_deps iface)
992 , vcat (map pprUsage (mi_usages iface))
993 , pprFixities (mi_fixities iface)
994 , vcat (map pprIfaceDecl (mi_decls iface))
995 , vcat (map ppr (mi_insts iface))
996 , vcat (map ppr (mi_rules iface))
997 , pprDeprecs (mi_deprecs iface)
1000 pp_boot | mi_boot iface = ptext SLIT("[boot]")
1002 ppr_package HomePackage = empty
1003 ppr_package (ExtPackage id) = doubleQuotes (ppr id)
1005 exp_vers = mi_exp_vers iface
1006 rule_vers = mi_rule_vers iface
1008 pp_sub_vers | exp_vers == initialVersion && rule_vers == initialVersion = empty
1009 | otherwise = brackets (ppr exp_vers <+> ppr rule_vers)
1012 When printing export lists, we print like this:
1014 AvailTC C [C, x, y] C(x,y)
1015 AvailTC C [x, y] C!(x,y) -- Exporting x, y but not C
1018 pprExport :: IfaceExport -> SDoc
1019 pprExport (mod, items)
1020 = hsep [ ptext SLIT("export"), ppr mod, hsep (map pp_avail items) ]
1022 pp_avail :: GenAvailInfo OccName -> SDoc
1023 pp_avail (Avail occ) = ppr occ
1024 pp_avail (AvailTC _ []) = empty
1025 pp_avail (AvailTC n (n':ns))
1026 | n==n' = ppr n <> pp_export ns
1027 | otherwise = ppr n <> char '|' <> pp_export (n':ns)
1029 pp_export [] = empty
1030 pp_export names = braces (hsep (map ppr names))
1032 pprUsage :: Usage -> SDoc
1034 = hsep [ptext SLIT("import"), ppr (usg_name usage),
1035 int (usg_mod usage),
1036 pp_export_version (usg_exports usage),
1037 int (usg_rules usage),
1038 pp_versions (usg_entities usage) ]
1040 pp_versions nvs = hsep [ ppr n <+> int v | (n,v) <- nvs ]
1041 pp_export_version Nothing = empty
1042 pp_export_version (Just v) = int v
1044 pprDeps :: Dependencies -> SDoc
1045 pprDeps (Deps { dep_mods = mods, dep_pkgs = pkgs, dep_orphs = orphs})
1046 = vcat [ptext SLIT("module dependencies:") <+> fsep (map ppr_mod mods),
1047 ptext SLIT("package dependencies:") <+> fsep (map ppr pkgs),
1048 ptext SLIT("orphans:") <+> fsep (map ppr orphs)
1051 ppr_mod (mod_name, boot) = ppr mod_name <+> ppr_boot boot
1052 ppr_boot True = text "[boot]"
1053 ppr_boot False = empty
1055 pprIfaceDecl :: (Version, IfaceDecl) -> SDoc
1056 pprIfaceDecl (ver, decl)
1057 = ppr_vers ver <+> ppr decl
1059 -- Print the version for the decl
1060 ppr_vers v | v == initialVersion = empty
1063 pprFixities :: [(OccName, Fixity)] -> SDoc
1064 pprFixities [] = empty
1065 pprFixities fixes = ptext SLIT("fixities") <+> pprWithCommas pprFix fixes
1067 pprFix (occ,fix) = ppr fix <+> ppr occ
1069 pprDeprecs NoDeprecs = empty
1070 pprDeprecs (DeprecAll txt) = ptext SLIT("Deprecate all") <+> doubleQuotes (ftext txt)
1071 pprDeprecs (DeprecSome prs) = ptext SLIT("Deprecate") <+> vcat (map pprDeprec prs)
1073 pprDeprec (name, txt) = ppr name <+> doubleQuotes (ftext txt)