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 checkOldIface -- See if recompilation is required, by
15 -- comparing version information
19 -----------------------------------------------
20 MkIface.lhs deals with versioning
21 -----------------------------------------------
23 Here's the version-related info in an interface file
25 module Foo 8 -- module-version
26 3 -- export-list-version
28 Usages: -- Version info for what this compilation of Foo imported
29 Baz 3 -- Module version
30 [4] -- The export-list version if Foo depended on it
31 (g,2) -- Function and its version
32 (T,1) -- Type and its version
34 <version> f :: Int -> Int {- Unfolding: \x -> Wib.t[2] x -}
35 -- The [2] says that f's unfolding
36 -- mentions verison 2 of Wib.t
38 -----------------------------------------------
40 -----------------------------------------------
43 * In the mi_usages information in an interface, we record the
44 version number of each free variable of the module
46 * In mkIface, we compute the version number of each exported thing A.f
47 by comparing its A.f's info with its new info, and bumping its
48 version number if it differs. If A.f mentions B.g, and B.g's version
49 number has changed, then we count A.f as having changed too.
51 * In checkOldIface we compare the mi_usages for the module with
52 the actual version info for all each thing recorded in mi_usages
57 We count A.f as changing if its fixity changes
61 If a rule changes, we want to recompile any module that might be
62 affected by that rule. For non-orphan rules, this is relatively easy.
63 If module M defines f, and a rule for f, just arrange that the version
64 number for M.f changes if any of the rules for M.f change. Any module
65 that does not depend on M.f can't be affected by the rule-change
68 Orphan rules (ones whose 'head function' is not defined in M) are
69 harder. Here's what we do.
71 * We have a per-module orphan-rule version number which changes if
72 any orphan rule changes. (It's unaffected by non-orphan rules.)
74 * We record usage info for any orphan module 'below' this one,
75 giving the orphan-rule version number. We recompile if this
78 The net effect is that if an orphan rule changes, we recompile every
79 module above it. That's very conservative, but it's devilishly hard
80 to know what it might affect, so we just have to be conservative.
84 In an iface file we have
86 instance Eq a => Eq [a] = dfun29
89 We have a version number for dfun29, covering its unfolding
90 etc. Suppose we are compiling a module M that imports A only
91 indirectly. If typechecking M uses this instance decl, we record the
92 dependency on A.dfun29 as if it were a free variable of the module
93 (via the tcg_inst_usages accumulator). That means that A will appear
94 in M's usage list. If the shape of the instance declaration changes,
95 then so will dfun29's version, triggering a recompilation.
97 Adding an instance declaration, or changing an instance decl that is
98 not currently used, is more tricky. (This really only makes a
99 difference when we have overlapping instance decls, because then the
100 new instance decl might kick in to override the old one.) We handle
101 this in a very similar way that we handle rules above.
103 * For non-orphan instance decls, identify one locally-defined tycon/class
104 mentioned in the decl. Treat the instance decl as part of the defn of that
105 tycon/class, so that if the shape of the instance decl changes, so does the
106 tycon/class; that in turn will force recompilation of anything that uses
109 * For orphan instance decls, act the same way as for orphan rules.
110 Indeed, we use the same global orphan-rule version number.
114 mkUsageInfo figures out what the ``usage information'' for this
115 moudule is; that is, what it must record in its interface file as the
118 We produce a line for every module B below the module, A, currently being
121 to record the fact that A does import B indirectly. This is used to decide
122 to look to look for B.hi rather than B.hi-boot when compiling a module that
123 imports A. This line says that A imports B, but uses nothing in it.
124 So we'll get an early bale-out when compiling A if B's version changes.
126 The usage information records:
129 \item (a) anything reachable from its body code
130 \item (b) any module exported with a @module Foo@
131 \item (c) anything reachable from an exported item
134 Why (b)? Because if @Foo@ changes then this module's export list
135 will change, so we must recompile this module at least as far as
136 making a new interface file --- but in practice that means complete
139 Why (c)? Consider this:
141 module A( f, g ) where | module B( f ) where
142 import B( f ) | f = h 3
146 Here, @B.f@ isn't used in A. Should we nevertheless record @B.f@ in
147 @A@'s usages? Our idea is that we aren't going to touch A.hi if it is
148 *identical* to what it was before. If anything about @B.f@ changes
149 than anyone who imports @A@ should be recompiled in case they use
150 @B.f@ (they'll get an early exit if they don't). So, if anything
151 about @B.f@ changes we'd better make sure that something in A.hi
152 changes, and the convenient way to do that is to record the version
153 number @B.f@ in A.hi in the usage list. If B.f changes that'll force a
154 complete recompiation of A, which is overkill but it's the only way to
155 write a new, slightly different, A.hi.
157 But the example is tricker. Even if @B.f@ doesn't change at all,
158 @B.h@ may do so, and this change may not be reflected in @f@'s version
159 number. But with -O, a module that imports A must be recompiled if
160 @B.h@ changes! So A must record a dependency on @B.h@. So we treat
161 the occurrence of @B.f@ in the export list *just as if* it were in the
162 code of A, and thereby haul in all the stuff reachable from it.
164 *** Conclusion: if A mentions B.f in its export list,
165 behave just as if A mentioned B.f in its source code,
166 and slurp in B.f and all its transitive closure ***
168 [NB: If B was compiled with -O, but A isn't, we should really *still*
169 haul in all the unfoldings for B, in case the module that imports A *is*
170 compiled with -O. I think this is the case.]
174 #include "HsVersions.h"
177 import Packages ( isHomeModule, PackageIdH(..) )
178 import IfaceSyn ( IfaceDecl(..), IfaceClassOp(..), IfaceConDecl(..),
179 IfaceRule(..), IfaceInst(..), IfaceExtName(..), IfaceTyCon(..),
180 eqIfDecl, eqIfRule, eqIfInst, IfaceEq(..), (&&&), bool,
181 eqMaybeBy, eqListBy, visibleIfConDecls,
182 tyThingToIfaceDecl, dfunToIfaceInst, coreRuleToIfaceRule )
183 import LoadIface ( readIface, loadInterface, ifaceInstGates )
184 import BasicTypes ( Version, initialVersion, bumpVersion )
186 import TcRnTypes ( mkModDeps )
187 import TcType ( isFFITy )
188 import HscTypes ( ModIface(..), TyThing(..),
189 ModGuts(..), ModGuts, IfaceExport,
190 GhciMode(..), HscEnv(..), hscEPS,
191 Dependencies(..), FixItem(..),
192 ModSummary(..), msHiFilePath,
193 mkIfaceDepCache, mkIfaceFixCache, mkIfaceVerCache,
195 GenAvailInfo(..), availName,
196 ExternalPackageState(..),
197 Usage(..), IsBootInterface,
198 Deprecs(..), IfaceDeprecs, Deprecations,
204 import Name ( Name, nameModule, nameOccName, nameParent,
205 isExternalName, nameParent_maybe, isWiredInName,
209 import OccName ( OccName, OccEnv, mkOccEnv, lookupOccEnv, emptyOccEnv,
211 OccSet, emptyOccSet, elemOccSet, occSetElts,
212 extendOccSet, extendOccSetList,
213 isEmptyOccSet, intersectOccSet, intersectsOccSet,
215 import TyCon ( tyConDataCons, isNewTyCon, newTyConRep )
216 import Class ( classSelIds )
217 import DataCon ( dataConName, dataConFieldLabels )
218 import Module ( Module, moduleFS,
219 ModLocation(..), mkSysModuleFS, moduleUserString,
220 ModuleEnv, emptyModuleEnv, lookupModuleEnv,
224 import DriverUtil ( createDirectoryHierarchy, directoryOf )
225 import Util ( sortLe, seqList )
226 import Binary ( getBinFileWithDict )
227 import BinIface ( writeBinIface, v_IgnoreHiWay )
228 import Unique ( Unique, Uniquable(..) )
229 import ErrUtils ( dumpIfSet_dyn, showPass )
230 import Digraph ( stronglyConnComp, SCC(..) )
231 import SrcLoc ( SrcSpan )
235 import DATA_IOREF ( writeIORef )
236 import Monad ( when )
237 import List ( insert )
238 import Maybes ( orElse, mapCatMaybes, isNothing, isJust,
239 fromJust, expectJust, MaybeErr(..) )
244 %************************************************************************
246 \subsection{Completing an interface}
248 %************************************************************************
253 -> Maybe ModIface -- The old interface, if we have it
254 -> ModGuts -- The compiled, tidied module
255 -> IO ModIface -- The new one, complete with decls and versions
257 -- a) Builds the ModIface
258 -- b) Writes it out to a file if necessary
260 mkIface hsc_env location maybe_old_iface
261 guts@ModGuts{ mg_module = this_mod,
265 mg_exports = exports,
266 mg_fix_env = fix_env,
267 mg_deprecs = src_deprecs,
270 mg_types = type_env }
271 = do { eps <- hscEPS hsc_env
272 ; let { ext_nm = mkExtNameFn hsc_env eps this_mod
273 ; local_things = [thing | thing <- typeEnvElts type_env,
274 not (isWiredInName (getName thing)) ]
275 -- Do not export anything about wired-in things
276 -- (GHC knows about them already)
278 ; abstract_tcs :: NameSet -- TyCons and Classes whose representation is not exposed
280 | not omit_prags = emptyNameSet -- In the -O case, nothing is abstract
281 | otherwise = mkNameSet [ getName thing
282 | thing <- local_things
283 , not (mustExposeThing exports thing)]
285 ; decls = [ tyThingToIfaceDecl omit_prags abstract_tcs ext_nm thing
286 | thing <- local_things, wantDeclFor exports abstract_tcs thing ]
287 -- Don't put implicit Ids and class tycons in the interface file
289 ; fixities = [(occ,fix) | FixItem occ fix _ <- nameEnvElts fix_env]
290 ; deprecs = mkIfaceDeprec src_deprecs
293 | otherwise = sortLe le_rule $
294 map (coreRuleToIfaceRule this_mod ext_nm) rules
295 ; iface_insts = sortLe le_inst (map dfunToIfaceInst insts)
297 ; intermediate_iface = ModIface {
298 mi_module = this_mod,
299 mi_package = HomePackage,
303 mi_exports = mkIfaceExports exports,
304 mi_insts = iface_insts,
305 mi_rules = iface_rules,
306 mi_fixities = fixities,
307 mi_deprecs = deprecs,
309 -- Left out deliberately: filled in by addVersionInfo
310 mi_mod_vers = initialVersion,
311 mi_exp_vers = initialVersion,
312 mi_rule_vers = initialVersion,
313 mi_orphan = False, -- Always set by addVersionInfo, but
314 -- it's a strict field, so we can't omit it.
315 mi_decls = deliberatelyOmitted "decls",
316 mi_ver_fn = deliberatelyOmitted "ver_fn",
318 -- And build the cached values
319 mi_dep_fn = mkIfaceDepCache deprecs,
320 mi_fix_fn = mkIfaceFixCache fixities }
322 -- Add version information
323 ; (new_iface, no_change_at_all, pp_diffs, pp_orphs)
324 = _scc_ "versioninfo"
325 addVersionInfo maybe_old_iface intermediate_iface decls
328 -- Write the interface file, if necessary
329 ; when (not no_change_at_all && ghci_mode /= Interactive) $ do
330 createDirectoryHierarchy (directoryOf hi_file_path)
331 writeBinIface hi_file_path new_iface
334 ; when (isJust pp_orphs && dopt Opt_WarnOrphans dflags)
335 (printDump (fromJust pp_orphs))
336 ; when (dopt Opt_D_dump_hi_diffs dflags) (printDump pp_diffs)
337 ; dumpIfSet_dyn dflags Opt_D_dump_hi "FINAL INTERFACE"
338 (pprModIface new_iface)
342 r1 `le_rule` r2 = ifRuleName r1 <= ifRuleName r2
343 i1 `le_inst` i2 = ifDFun i1 <= ifDFun i2
345 dflags = hsc_dflags hsc_env
346 ghci_mode = hsc_mode hsc_env
347 omit_prags = dopt Opt_OmitInterfacePragmas dflags
348 hi_file_path = ml_hi_file location
351 mustExposeThing :: NameSet -> TyThing -> Bool
352 -- We are compiling without -O, and thus trying to write as little as
353 -- possible into the interface file. But we must expose the details of
354 -- any data types and classes whose constructors, fields, methods are
355 -- visible to an importing module
356 mustExposeThing exports (ATyCon tc)
357 = any exported_data_con (tyConDataCons tc)
358 -- Expose rep if any datacon or field is exported
360 || (isNewTyCon tc && isFFITy (snd (newTyConRep tc)))
361 -- Expose the rep for newtypes if the rep is an FFI type.
362 -- For a very annoying reason. 'Foreign import' is meant to
363 -- be able to look through newtypes transparently, but it
364 -- can only do that if it can "see" the newtype representation
366 exported_data_con con
367 = any (`elemNameSet` exports) (dataConName con : dataConFieldLabels con)
369 mustExposeThing exports (AClass cls)
370 = any exported_class_op (classSelIds cls)
371 where -- Expose rep if any classs op is exported
372 exported_class_op op = getName op `elemNameSet` exports
374 mustExposeThing exports other = False
377 wantDeclFor :: NameSet -- User-exported things
378 -> NameSet -- Abstract things
380 wantDeclFor exports abstracts thing
381 | Just parent <- nameParent_maybe name -- An implicit thing
382 = parent `elemNameSet` abstracts && name `elemNameSet` exports
389 deliberatelyOmitted x = panic ("Deliberately omitted: " ++ x)
391 -----------------------------
392 mkExtNameFn :: HscEnv -> ExternalPackageState -> Module -> Name -> IfaceExtName
393 mkExtNameFn hsc_env eps this_mod
396 dflags = hsc_dflags hsc_env
397 hpt = hsc_HPT hsc_env
401 | mod == this_mod = case nameParent_maybe name of
402 Nothing -> LocalTop occ
403 Just par -> LocalTopSub occ (nameOccName par)
404 | isWiredInName name = ExtPkg mod occ
405 | isHomeModule dflags mod = HomePkg mod occ vers
406 | otherwise = ExtPkg mod occ
408 mod = nameModule name
409 occ = nameOccName name
410 par_occ = nameOccName (nameParent name)
411 -- The version of the *parent* is the one want
412 vers = lookupVersion mod par_occ
414 lookupVersion :: Module -> OccName -> Version
415 -- Even though we're looking up a home-package thing, in
416 -- one-shot mode the imported interfaces may be in the PIT
417 lookupVersion mod occ
418 = mi_ver_fn iface occ `orElse`
419 pprPanic "lookupVers1" (ppr mod <+> ppr occ)
421 iface = lookupIfaceByModule hpt pit mod `orElse`
422 pprPanic "lookupVers2" (ppr mod <+> ppr occ)
424 -----------------------------
425 -- Compute version numbers for local decls
427 addVersionInfo :: Maybe ModIface -- The old interface, read from M.hi
428 -> ModIface -- The new interface decls (lacking decls)
429 -> [IfaceDecl] -- The new decls
431 Bool, -- True <=> no changes at all; no need to write new Iface
433 Maybe SDoc) -- Warnings about orphans
435 addVersionInfo Nothing new_iface new_decls
436 -- No old interface, so definitely write a new one!
437 = (new_iface { mi_orphan = anyNothing getInstKey (mi_insts new_iface)
438 || anyNothing getRuleKey (mi_rules new_iface),
439 mi_decls = [(initialVersion, decl) | decl <- new_decls],
440 mi_ver_fn = \n -> Just initialVersion },
442 ptext SLIT("No old interface file"),
443 pprOrphans orph_insts orph_rules)
445 orph_insts = filter (isNothing . getInstKey) (mi_insts new_iface)
446 orph_rules = filter (isNothing . getRuleKey) (mi_rules new_iface)
448 addVersionInfo (Just old_iface@(ModIface { mi_mod_vers = old_mod_vers,
449 mi_exp_vers = old_exp_vers,
450 mi_rule_vers = old_rule_vers,
451 mi_decls = old_decls,
452 mi_ver_fn = old_decl_vers,
453 mi_fix_fn = old_fixities }))
454 new_iface@(ModIface { mi_fix_fn = new_fixities })
457 | no_change_at_all = (old_iface, True, ptext SLIT("Interface file unchanged"), pp_orphs)
458 | otherwise = (final_iface, False, vcat [ptext SLIT("Interface file has changed"),
459 nest 2 pp_diffs], pp_orphs)
461 final_iface = new_iface { mi_mod_vers = bump_unless no_output_change old_mod_vers,
462 mi_exp_vers = bump_unless no_export_change old_exp_vers,
463 mi_rule_vers = bump_unless no_rule_change old_rule_vers,
464 mi_orphan = not (null new_orph_rules && null new_orph_insts),
465 mi_decls = decls_w_vers,
466 mi_ver_fn = mkIfaceVerCache decls_w_vers }
468 decls_w_vers = [(add_vers decl, decl) | decl <- new_decls]
471 (old_non_orph_insts, old_orph_insts) = mkRuleMap getInstKey (mi_insts old_iface)
472 (new_non_orph_insts, new_orph_insts) = mkRuleMap getInstKey (mi_insts new_iface)
473 same_insts occ = eqMaybeBy (eqListBy eqIfInst)
474 (lookupOccEnv old_non_orph_insts occ)
475 (lookupOccEnv new_non_orph_insts occ)
477 (old_non_orph_rules, old_orph_rules) = mkRuleMap getRuleKey (mi_rules old_iface)
478 (new_non_orph_rules, new_orph_rules) = mkRuleMap getRuleKey (mi_rules new_iface)
479 same_rules occ = eqMaybeBy (eqListBy eqIfRule)
480 (lookupOccEnv old_non_orph_rules occ)
481 (lookupOccEnv new_non_orph_rules occ)
483 -- Computing what changed
484 no_output_change = no_decl_change && no_rule_change &&
485 no_export_change && no_deprec_change
486 no_export_change = mi_exports new_iface == mi_exports old_iface -- Kept sorted
487 no_decl_change = isEmptyOccSet changed_occs
488 no_rule_change = not (changedWrt changed_occs (eqListBy eqIfRule old_orph_rules new_orph_rules)
489 || changedWrt changed_occs (eqListBy eqIfInst old_orph_insts new_orph_insts))
490 no_deprec_change = mi_deprecs new_iface == mi_deprecs old_iface
492 -- If the usages havn't changed either, we don't need to write the interface file
493 no_other_changes = mi_usages new_iface == mi_usages old_iface &&
494 mi_deps new_iface == mi_deps old_iface
495 no_change_at_all = no_output_change && no_other_changes
497 pp_diffs = vcat [pp_change no_export_change "Export list"
498 (ppr old_exp_vers <+> arrow <+> ppr (mi_exp_vers final_iface)),
499 pp_change no_rule_change "Rules"
500 (ppr old_rule_vers <+> arrow <+> ppr (mi_rule_vers final_iface)),
501 pp_change no_deprec_change "Deprecations" empty,
502 pp_change no_other_changes "Usages" empty,
504 pp_change True what info = empty
505 pp_change False what info = text what <+> ptext SLIT("changed") <+> info
508 old_decl_env = mkOccEnv [(ifName decl, decl) | (_,decl) <- old_decls]
509 same_fixity n = bool (old_fixities n == new_fixities n)
512 -- Adding version info
513 new_version = bumpVersion old_mod_vers
514 add_vers decl | occ `elemOccSet` changed_occs = new_version
515 | otherwise = expectJust "add_vers" (old_decl_vers occ)
516 -- If it's unchanged, there jolly well
517 where -- should be an old version number
521 changed_occs :: OccSet
522 changed_occs = computeChangedOccs eq_info
524 eq_info :: [(OccName, IfaceEq)]
525 eq_info = map check_eq new_decls
526 check_eq new_decl | Just old_decl <- lookupOccEnv old_decl_env occ
527 = (occ, new_decl `eqIfDecl` old_decl &&&
528 eq_indirects new_decl)
529 | otherwise {- No corresponding old decl -}
532 occ = ifName new_decl
534 eq_indirects :: IfaceDecl -> IfaceEq
535 -- When seeing if two decls are the same, remember to
536 -- check whether any relevant fixity or rules have changed
537 eq_indirects (IfaceId {ifName = occ}) = eq_ind_occ occ
538 eq_indirects (IfaceClass {ifName = cls_occ, ifSigs = sigs})
539 = same_insts cls_occ &&&
540 eq_ind_occs [op | IfaceClassOp op _ _ <- sigs]
541 eq_indirects (IfaceData {ifName = tc_occ, ifCons = cons})
542 = same_insts tc_occ &&& same_fixity tc_occ &&& -- The TyCon can have a fixity too
543 eq_ind_occs (map ifConOcc (visibleIfConDecls cons))
544 eq_indirects other = Equal -- Synonyms and foreign declarations
546 eq_ind_occ :: OccName -> IfaceEq -- For class ops and Ids; check fixity and rules
547 eq_ind_occ occ = same_fixity occ &&& same_rules occ
548 eq_ind_occs = foldr ((&&&) . eq_ind_occ) Equal
552 pp_decl_diffs :: SDoc -- Nothing => no changes
554 | isEmptyOccSet changed_occs = empty
556 = vcat [ptext SLIT("Changed occs:") <+> ppr (occSetElts changed_occs),
557 ptext SLIT("Version change for these decls:"),
558 nest 2 (vcat (map show_change new_decls))]
560 eq_env = mkOccEnv eq_info
562 | not (occ `elemOccSet` changed_occs) = empty
564 = vcat [ppr occ <+> ppr (old_decl_vers occ) <+> arrow <+> ppr new_version,
567 occ = ifName new_decl
568 why = case lookupOccEnv eq_env occ of
569 Just (EqBut occs) -> sep [ppr occ <> colon, ptext SLIT("Free vars (only) changed:"),
570 nest 2 (braces (fsep (map ppr (occSetElts
571 (occs `intersectOccSet` changed_occs)))))]
573 | Just old_decl <- lookupOccEnv old_decl_env occ
574 -> vcat [ptext SLIT("Old:") <+> ppr old_decl,
575 ptext SLIT("New:") <+> ppr new_decl]
577 -> ppr occ <+> ptext SLIT("only in new interface")
578 other -> pprPanic "MkIface.show_change" (ppr occ)
580 pp_orphs = pprOrphans new_orph_insts new_orph_rules
582 pprOrphans insts rules
583 | null insts && null rules = Nothing
586 if null insts then empty else
587 hang (ptext SLIT("Warning: orphan instances:"))
588 2 (vcat (map ppr insts)),
589 if null rules then empty else
590 hang (ptext SLIT("Warning: orphan rules:"))
591 2 (vcat (map ppr rules))
594 computeChangedOccs :: [(OccName, IfaceEq)] -> OccSet
595 computeChangedOccs eq_info
596 = foldl add_changes emptyOccSet (stronglyConnComp edges)
598 edges :: [((OccName,IfaceEq), Unique, [Unique])]
599 edges = [ (node, getUnique occ, map getUnique occs)
600 | node@(occ, iface_eq) <- eq_info
601 , let occs = case iface_eq of
602 EqBut occ_set -> occSetElts occ_set
605 -- Changes in declarations
606 add_changes :: OccSet -> SCC (OccName, IfaceEq) -> OccSet
607 add_changes so_far (AcyclicSCC (occ, iface_eq))
608 | changedWrt so_far iface_eq -- This one has changed
609 = extendOccSet so_far occ
610 add_changes so_far (CyclicSCC pairs)
611 | changedWrt so_far (foldr1 (&&&) (map snd pairs)) -- One of this group has changed
612 = extendOccSetList so_far (map fst pairs)
613 add_changes so_far other = so_far
615 changedWrt :: OccSet -> IfaceEq -> Bool
616 changedWrt so_far Equal = False
617 changedWrt so_far NotEqual = True
618 changedWrt so_far (EqBut kids) = so_far `intersectsOccSet` kids
620 ----------------------
621 -- mkRuleMap partitions instance decls or rules into
622 -- (a) an OccEnv for ones that are not orphans,
623 -- mapping the local OccName to a list of its decls
624 -- (b) a list of orphan decls
625 mkRuleMap :: (decl -> Maybe OccName) -- (Just occ) for a non-orphan decl, keyed by occ
626 -- Nothing for an orphan decl
627 -> [decl] -- Sorted into canonical order
628 -> (OccEnv [decl], -- Non-orphan decls associated with their key;
629 -- each sublist in canonical order
630 [decl]) -- Orphan decls; in canonical order
631 mkRuleMap get_key decls
632 = foldl go (emptyOccEnv, []) decls
634 go (non_orphs, orphs) d
635 | Just occ <- get_key d
636 = (extendOccEnv_C (\ ds _ -> d:ds) non_orphs occ [d], orphs)
637 | otherwise = (non_orphs, d:orphs)
639 -- getXxKey: find at least one local OccName that belongs to this decl
641 getInstKey :: IfaceInst -> Maybe OccName
642 getInstKey (IfaceInst {ifInstHead = inst_ty})
643 = case [occ | LocalTop occ <- cls_ext : tc_exts] of
647 (cls_ext, tcs) = ifaceInstGates inst_ty
648 tc_exts = [tc | IfaceTc tc <- tcs]
649 -- Ignore the wired-in IfaceTyCons; the class will do as the key
651 getRuleKey :: IfaceRule -> Maybe OccName
652 getRuleKey (IfaceRule {ifRuleHead = LocalTop occ}) = Just occ
653 getRuleKey other = Nothing
655 anyNothing :: (a -> Maybe b) -> [a] -> Bool
656 anyNothing p [] = False
657 anyNothing p (x:xs) = isNothing (p x) || anyNothing p xs
659 ----------------------
660 mkIfaceDeprec :: Deprecations -> IfaceDeprecs
661 mkIfaceDeprec NoDeprecs = NoDeprecs
662 mkIfaceDeprec (DeprecAll t) = DeprecAll t
663 mkIfaceDeprec (DeprecSome env) = DeprecSome (sortLe (<=) (nameEnvElts env))
665 ----------------------
666 bump_unless :: Bool -> Version -> Version
667 bump_unless True v = v -- True <=> no change
668 bump_unless False v = bumpVersion v
672 %*********************************************************
674 \subsection{Keeping track of what we've slurped, and version numbers}
676 %*********************************************************
680 mkUsageInfo :: HscEnv
681 -> ModuleEnv (Module, Maybe Bool, SrcSpan)
682 -> [(Module, IsBootInterface)]
683 -> NameSet -> IO [Usage]
684 mkUsageInfo hsc_env dir_imp_mods dep_mods used_names
685 = do { eps <- hscEPS hsc_env
686 ; let usages = mk_usage_info (eps_PIT eps) hsc_env
687 dir_imp_mods dep_mods used_names
688 ; usages `seqList` return usages }
689 -- seq the list of Usages returned: occasionally these
690 -- don't get evaluated for a while and we can end up hanging on to
691 -- the entire collection of Ifaces.
693 mk_usage_info pit hsc_env dir_imp_mods dep_mods proto_used_names
694 = mapCatMaybes mkUsage dep_mods
695 -- ToDo: do we need to sort into canonical order?
697 dflags = hsc_dflags hsc_env
698 hpt = hsc_HPT hsc_env
700 used_names = mkNameSet $ -- Eliminate duplicates
701 [ nameParent n -- Just record usage on the 'main' names
702 | n <- nameSetToList proto_used_names
703 , not (isWiredInName n) -- Don't record usages for wired-in names
704 , isExternalName n -- Ignore internal names
707 -- ent_map groups together all the things imported and used
708 -- from a particular module in this package
709 ent_map :: ModuleEnv [OccName]
710 ent_map = foldNameSet add_mv emptyModuleEnv used_names
711 add_mv name mv_map = extendModuleEnv_C add_item mv_map mod [occ]
713 occ = nameOccName name
714 mod = nameModule name
715 add_item occs _ = occ:occs
717 import_all mod = case lookupModuleEnv dir_imp_mods mod of
718 Just (_,imp_all,_) -> isNothing imp_all
721 -- We want to create a Usage for a home module if
722 -- a) we used something from; has something in used_names
723 -- b) we imported all of it, even if we used nothing from it
724 -- (need to recompile if its export list changes: export_vers)
725 -- c) is a home-package orphan module (need to recompile if its
726 -- instance decls change: rules_vers)
727 mkUsage :: (Module, Bool) -> Maybe Usage
728 mkUsage (mod_name, _)
729 | isNothing maybe_iface -- We can't depend on it if we didn't
730 || not (isHomeModule dflags mod) -- even open the interface!
734 = Nothing -- Record no usage info
737 = Just (Usage { usg_name = mod,
739 usg_exports = export_vers,
740 usg_entities = ent_vers,
741 usg_rules = rules_vers })
743 maybe_iface = lookupIfaceByModule hpt pit mod_name
744 -- In one-shot mode, the interfaces for home-package
745 -- modules accumulate in the PIT not HPT. Sigh.
747 Just iface = maybe_iface
748 mod = mi_module iface
749 orphan_mod = mi_orphan iface
750 version_env = mi_ver_fn iface
751 mod_vers = mi_mod_vers iface
752 rules_vers = mi_rule_vers iface
753 all_imported = import_all mod
754 export_vers | all_imported = Just (mi_exp_vers iface)
755 | otherwise = Nothing
757 -- The sort is to put them into canonical order
758 used_occs = lookupModuleEnv ent_map mod `orElse` []
759 ent_vers :: [(OccName,Version)]
760 ent_vers = [ (occ, version_env occ `orElse` initialVersion)
761 | occ <- sortLe (<=) used_occs]
765 mkIfaceExports :: NameSet -> [(Module, [GenAvailInfo OccName])]
766 -- Group by module and sort by occurrence
767 -- This keeps the list in canonical order
768 mkIfaceExports exports
769 = [ (mkSysModuleFS fs, eltsFM avails)
770 | (fs, avails) <- fmToList groupFM
773 groupFM :: FiniteMap FastString (FiniteMap FastString (GenAvailInfo OccName))
774 -- Deliberately use the FastString so we
775 -- get a canonical ordering
776 groupFM = foldl add emptyFM (nameSetToList exports)
778 add env name = addToFM_C add_avail env mod_fs
779 (unitFM avail_fs avail)
781 occ = nameOccName name
782 mod_fs = moduleFS (nameModule name)
783 avail | Just p <- nameParent_maybe name = AvailTC (nameOccName p) [occ]
784 | isTcOcc occ = AvailTC occ [occ]
785 | otherwise = Avail occ
786 avail_fs = occNameFS (availName avail)
787 add_avail avail_fm _ = addToFM_C add_item avail_fm avail_fs avail
789 add_item (AvailTC p occs) _ = AvailTC p (List.insert occ occs)
790 add_item (Avail n) _ = pprPanic "MkIface.addAvail" (ppr n <+> ppr name)
794 %************************************************************************
796 Load the old interface file for this module (unless
797 we have it aleady), and check whether it is up to date
800 %************************************************************************
803 checkOldIface :: HscEnv
805 -> Bool -- Source unchanged
806 -> Maybe ModIface -- Old interface from compilation manager, if any
807 -> IO (RecompileRequired, Maybe ModIface)
809 checkOldIface hsc_env mod_summary source_unchanged maybe_iface
810 = do { showPass (hsc_dflags hsc_env)
811 ("Checking old interface for " ++ moduleUserString (ms_mod mod_summary)) ;
813 ; initIfaceCheck hsc_env $
814 check_old_iface mod_summary source_unchanged maybe_iface
817 check_old_iface mod_summary source_unchanged maybe_iface
818 = -- CHECK WHETHER THE SOURCE HAS CHANGED
819 ifM (not source_unchanged)
820 (traceHiDiffs (nest 4 (text "Source file changed or recompilation check turned off")))
823 -- If the source has changed and we're in interactive mode, avoid reading
824 -- an interface; just return the one we might have been supplied with.
825 getGhciMode `thenM` \ ghci_mode ->
826 if (ghci_mode == Interactive) && not source_unchanged then
827 returnM (outOfDate, maybe_iface)
830 case maybe_iface of {
831 Just old_iface -> -- Use the one we already have
832 checkVersions source_unchanged old_iface `thenM` \ recomp ->
833 returnM (recomp, Just old_iface)
837 -- Try and read the old interface for the current module
838 -- from the .hi file left from the last time we compiled it
840 iface_path = msHiFilePath mod_summary
842 readIface (ms_mod mod_summary) iface_path False `thenM` \ read_result ->
843 case read_result of {
844 Failed err -> -- Old interface file not found, or garbled; give up
845 traceIf (text "FYI: cannot read old interface file:"
846 $$ nest 4 err) `thenM_`
847 returnM (outOfDate, Nothing)
851 -- We have got the old iface; check its versions
852 checkVersions source_unchanged iface `thenM` \ recomp ->
853 returnM (recomp, Just iface)
857 @recompileRequired@ is called from the HscMain. It checks whether
858 a recompilation is required. It needs access to the persistent state,
859 finder, etc, because it may have to load lots of interface files to
860 check their versions.
863 type RecompileRequired = Bool
864 upToDate = False -- Recompile not required
865 outOfDate = True -- Recompile required
867 checkVersions :: Bool -- True <=> source unchanged
868 -> ModIface -- Old interface
869 -> IfG RecompileRequired
870 checkVersions source_unchanged iface
871 | not source_unchanged
874 = do { traceHiDiffs (text "Considering whether compilation is required for" <+>
875 ppr (mi_module iface) <> colon)
877 -- Source code unchanged and no errors yet... carry on
879 -- First put the dependent-module info, read from the old interface, into the envt,
880 -- so that when we look for interfaces we look for the right one (.hi or .hi-boot)
882 -- It's just temporary because either the usage check will succeed
883 -- (in which case we are done with this module) or it'll fail (in which
884 -- case we'll compile the module from scratch anyhow).
886 -- We do this regardless of compilation mode
887 ; updateEps_ $ \eps -> eps { eps_is_boot = mod_deps }
889 ; checkList [checkModUsage u | u <- mi_usages iface]
892 -- This is a bit of a hack really
893 mod_deps :: ModuleEnv (Module, IsBootInterface)
894 mod_deps = mkModDeps (dep_mods (mi_deps iface))
896 checkModUsage :: Usage -> IfG RecompileRequired
897 -- Given the usage information extracted from the old
898 -- M.hi file for the module being compiled, figure out
899 -- whether M needs to be recompiled.
901 checkModUsage (Usage { usg_name = mod_name, usg_mod = old_mod_vers,
902 usg_rules = old_rule_vers,
903 usg_exports = maybe_old_export_vers,
904 usg_entities = old_decl_vers })
905 = -- Load the imported interface is possible
907 doc_str = sep [ptext SLIT("need version info for"), ppr mod_name]
909 traceHiDiffs (text "Checking usages for module" <+> ppr mod_name) `thenM_`
911 loadInterface doc_str mod_name ImportBySystem `thenM` \ mb_iface ->
912 -- Load the interface, but don't complain on failure;
913 -- Instead, get an Either back which we can test
916 Failed exn -> (out_of_date (sep [ptext SLIT("Can't find version number for module"),
918 -- Couldn't find or parse a module mentioned in the
919 -- old interface file. Don't complain -- it might just be that
920 -- the current module doesn't need that import and it's been deleted
924 new_mod_vers = mi_mod_vers iface
925 new_decl_vers = mi_ver_fn iface
926 new_export_vers = mi_exp_vers iface
927 new_rule_vers = mi_rule_vers iface
930 checkModuleVersion old_mod_vers new_mod_vers `thenM` \ recompile ->
931 if not recompile then
936 if checkExportList maybe_old_export_vers new_export_vers then
937 out_of_date_vers (ptext SLIT(" Export list changed"))
938 (fromJust maybe_old_export_vers)
943 if old_rule_vers /= new_rule_vers then
944 out_of_date_vers (ptext SLIT(" Rules changed"))
945 old_rule_vers new_rule_vers
948 -- CHECK ITEMS ONE BY ONE
949 checkList [checkEntityUsage new_decl_vers u | u <- old_decl_vers] `thenM` \ recompile ->
951 returnM outOfDate -- This one failed, so just bail out now
953 up_to_date (ptext SLIT(" Great! The bits I use are up to date"))
956 ------------------------
957 checkModuleVersion old_mod_vers new_mod_vers
958 | new_mod_vers == old_mod_vers
959 = up_to_date (ptext SLIT("Module version unchanged"))
962 = out_of_date_vers (ptext SLIT(" Module version has changed"))
963 old_mod_vers new_mod_vers
965 ------------------------
966 checkExportList Nothing new_vers = upToDate
967 checkExportList (Just v) new_vers = v /= new_vers
969 ------------------------
970 checkEntityUsage new_vers (name,old_vers)
971 = case new_vers name of
973 Nothing -> -- We used it before, but it ain't there now
974 out_of_date (sep [ptext SLIT("No longer exported:"), ppr name])
976 Just new_vers -- It's there, but is it up to date?
977 | new_vers == old_vers -> traceHiDiffs (text " Up to date" <+> ppr name <+> parens (ppr new_vers)) `thenM_`
979 | otherwise -> out_of_date_vers (ptext SLIT(" Out of date:") <+> ppr name)
982 up_to_date msg = traceHiDiffs msg `thenM_` returnM upToDate
983 out_of_date msg = traceHiDiffs msg `thenM_` returnM outOfDate
984 out_of_date_vers msg old_vers new_vers
985 = out_of_date (hsep [msg, ppr old_vers, ptext SLIT("->"), ppr new_vers])
987 ----------------------
988 checkList :: [IfG RecompileRequired] -> IfG RecompileRequired
989 -- This helper is used in two places
990 checkList [] = returnM upToDate
991 checkList (check:checks) = check `thenM` \ recompile ->
998 %************************************************************************
1002 %************************************************************************
1005 showIface :: FilePath -> IO ()
1006 -- Raad binary interface, and print it out
1007 showIface filename = do
1008 -- skip the version check; we don't want to worry about profiled vs.
1009 -- non-profiled interfaces, for example.
1010 writeIORef v_IgnoreHiWay True
1011 iface <- Binary.getBinFileWithDict filename
1012 printDump (pprModIface iface)
1018 pprModIface :: ModIface -> SDoc
1021 = vcat [ ptext SLIT("interface")
1022 <+> ppr_package (mi_package iface)
1023 <+> ppr (mi_module iface) <+> pp_boot
1024 <+> ppr (mi_mod_vers iface) <+> pp_sub_vers
1025 <+> (if mi_orphan iface then ptext SLIT("[orphan module]") else empty)
1026 <+> int opt_HiVersion
1027 <+> ptext SLIT("where")
1028 , vcat (map pprExport (mi_exports iface))
1029 , pprDeps (mi_deps iface)
1030 , vcat (map pprUsage (mi_usages iface))
1031 , pprFixities (mi_fixities iface)
1032 , vcat (map pprIfaceDecl (mi_decls iface))
1033 , vcat (map ppr (mi_insts iface))
1034 , vcat (map ppr (mi_rules iface))
1035 , pprDeprecs (mi_deprecs iface)
1038 pp_boot | mi_boot iface = ptext SLIT("[boot]")
1040 ppr_package HomePackage = empty
1041 ppr_package (ExtPackage id) = doubleQuotes (ppr id)
1043 exp_vers = mi_exp_vers iface
1044 rule_vers = mi_rule_vers iface
1046 pp_sub_vers | exp_vers == initialVersion && rule_vers == initialVersion = empty
1047 | otherwise = brackets (ppr exp_vers <+> ppr rule_vers)
1050 When printing export lists, we print like this:
1052 AvailTC C [C, x, y] C(x,y)
1053 AvailTC C [x, y] C!(x,y) -- Exporting x, y but not C
1056 pprExport :: IfaceExport -> SDoc
1057 pprExport (mod, items)
1058 = hsep [ ptext SLIT("export"), ppr mod, hsep (map pp_avail items) ]
1060 pp_avail :: GenAvailInfo OccName -> SDoc
1061 pp_avail (Avail occ) = ppr occ
1062 pp_avail (AvailTC _ []) = empty
1063 pp_avail (AvailTC n (n':ns))
1064 | n==n' = ppr n <> pp_export ns
1065 | otherwise = ppr n <> char '|' <> pp_export (n':ns)
1067 pp_export [] = empty
1068 pp_export names = braces (hsep (map ppr names))
1070 pprUsage :: Usage -> SDoc
1072 = hsep [ptext SLIT("import"), ppr (usg_name usage),
1073 int (usg_mod usage),
1074 pp_export_version (usg_exports usage),
1075 int (usg_rules usage),
1076 pp_versions (usg_entities usage) ]
1078 pp_versions nvs = hsep [ ppr n <+> int v | (n,v) <- nvs ]
1079 pp_export_version Nothing = empty
1080 pp_export_version (Just v) = int v
1082 pprDeps :: Dependencies -> SDoc
1083 pprDeps (Deps { dep_mods = mods, dep_pkgs = pkgs, dep_orphs = orphs})
1084 = vcat [ptext SLIT("module dependencies:") <+> fsep (map ppr_mod mods),
1085 ptext SLIT("package dependencies:") <+> fsep (map ppr pkgs),
1086 ptext SLIT("orphans:") <+> fsep (map ppr orphs)
1089 ppr_mod (mod_name, boot) = ppr mod_name <+> ppr_boot boot
1090 ppr_boot True = text "[boot]"
1091 ppr_boot False = empty
1093 pprIfaceDecl :: (Version, IfaceDecl) -> SDoc
1094 pprIfaceDecl (ver, decl)
1095 = ppr_vers ver <+> ppr decl
1097 -- Print the version for the decl
1098 ppr_vers v | v == initialVersion = empty
1101 pprFixities :: [(OccName, Fixity)] -> SDoc
1102 pprFixities [] = empty
1103 pprFixities fixes = ptext SLIT("fixities") <+> pprWithCommas pprFix fixes
1105 pprFix (occ,fix) = ppr fix <+> ppr occ
1107 pprDeprecs NoDeprecs = empty
1108 pprDeprecs (DeprecAll txt) = ptext SLIT("Deprecate all") <+> doubleQuotes (ftext txt)
1109 pprDeprecs (DeprecSome prs) = ptext SLIT("Deprecate") <+> vcat (map pprDeprec prs)
1111 pprDeprec (name, txt) = ppr name <+> doubleQuotes (ftext txt)