1. 16 Jul, 2018 1 commit
    • Simon Marlow's avatar
      Support the GHCi debugger with -fexternal-interpreter · 3bdf0d01
      Simon Marlow authored
      * All the tests in tests/ghci.debugger now pass with
        -fexternal-interpreter. These tests are now run with the ghci-ext way
        in addition to the normal way so we won't break it in the future.
      
      * I removed all the unsafeCoerce# calls from RtClosureInspect. Yay!
      
      The main changes are:
      
      * New messages: GetClosure and Seq.  GetClosure is a remote interface to
        GHC.Exts.Heap.getClosureData, which required Binary instances for
        various datatypes. Fortunately this wasn't too painful thanks to
        DeriveGeneric.
      
      * No cheating by unsafeCoercing values when printing them. Now we have
        to turn the Closure representation back into the native representation
        when printing Int, Float, Double, Integer and Char. Of these, Integer
        was the most painful - we now have a dependency on integer-gmp due to
        needing access to the representation.
      
      * Fixed a bug in rts/Heap.c - it was bogusly returning stack content as
        pointers for an AP_STACK closure.
      
      Test Plan:
      * `cd testsuite/tests/ghci.debugger && make`
      * validate
      
      Reviewers: bgamari, patrickdoc, nomeata, angerman, hvr, erikd, goldfire
      
      Subscribers: alpmestan, snowleopard, rwbarton, thomie, carter
      
      GHC Trac Issues: #13184
      
      Differential Revision: https://phabricator.haskell.org/D4955
      3bdf0d01
  2. 19 Sep, 2017 1 commit
    • Herbert Valerio Riedel's avatar
      compiler: introduce custom "GhcPrelude" Prelude · f63bc730
      Herbert Valerio Riedel authored
      This switches the compiler/ component to get compiled with
      -XNoImplicitPrelude and a `import GhcPrelude` is inserted in all
      modules.
      
      This is motivated by the upcoming "Prelude" re-export of
      `Semigroup((<>))` which would cause lots of name clashes in every
      modulewhich imports also `Outputable`
      
      Reviewers: austin, goldfire, bgamari, alanz, simonmar
      
      Reviewed By: bgamari
      
      Subscribers: goldfire, rwbarton, thomie, mpickering, bgamari
      
      Differential Revision: https://phabricator.haskell.org/D3989
      f63bc730
  3. 01 Mar, 2017 1 commit
    • David Feuer's avatar
      Upgrade UniqSet to a newtype · cbe569a5
      David Feuer authored
      The fundamental problem with `type UniqSet = UniqFM` is that `UniqSet`
      has a key invariant `UniqFM` does not. For example, `fmap` over
      `UniqSet` will generally produce nonsense.
      
      * Upgrade `UniqSet` from a type synonym to a newtype.
      
      * Remove unused and shady `extendVarSet_C` and `addOneToUniqSet_C`.
      
      * Use cached unique in `tyConsOfType` by replacing
        `unitNameEnv (tyConName tc) tc` with `unitUniqSet tc`.
      
      Reviewers: austin, hvr, goldfire, simonmar, niteria, bgamari
      
      Reviewed By: niteria
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D3146
      cbe569a5
  4. 20 Jan, 2017 1 commit
    • Phil de Joux's avatar
      Show explicit quantifiers in conflicting definitions error · 33140f41
      Phil de Joux authored
      This fixes #12441, where definitions in a Haskell module and its boot
      file which differed only in their quantifiers produced a confusing error
      message. Here we teach GHC to always show quantifiers for these errors.
      
      Reviewers: goldfire, simonmar, erikd, austin, hvr, bgamari
      
      Reviewed By: bgamari
      
      Subscribers: snowleopard, simonpj, mpickering, thomie
      
      Differential Revision: https://phabricator.haskell.org/D2734
      
      GHC Trac Issues: #12441
      33140f41
  5. 19 Jan, 2017 1 commit
    • Richard Eisenberg's avatar
      Update levity polymorphism · e7985ed2
      Richard Eisenberg authored
      This commit implements the proposal in
      https://github.com/ghc-proposals/ghc-proposals/pull/29 and
      https://github.com/ghc-proposals/ghc-proposals/pull/35.
      
      Here are some of the pieces of that proposal:
      
      * Some of RuntimeRep's constructors have been shortened.
      
      * TupleRep and SumRep are now parameterized over a list of RuntimeReps.
      * This
      means that two types with the same kind surely have the same
      representation.
      Previously, all unboxed tuples had the same kind, and thus the fact
      above was
      false.
      
      * RepType.typePrimRep and friends now return a *list* of PrimReps. These
      functions can now work successfully on unboxed tuples. This change is
      necessary because we allow abstraction over unboxed tuple types and so
      cannot
      always handle unboxed tuples specially as we did before.
      
      * We sometimes have to create an Id from a PrimRep. I thus split PtrRep
      * into
      LiftedRep and UnliftedRep, so that the created Ids have the right
      strictness.
      
      * The RepType.RepType type was removed, as it didn't seem to help with
      * much.
      
      * The RepType.repType function is also removed, in favor of typePrimRep.
      
      * I have waffled a good deal on whether or not to keep VoidRep in
      TyCon.PrimRep. In the end, I decided to keep it there. PrimRep is *not*
      represented in RuntimeRep, and typePrimRep will never return a list
      including
      VoidRep. But it's handy to have in, e.g., ByteCodeGen and friends. I can
      imagine another design choice where we have a PrimRepV type that is
      PrimRep
      with an extra constructor. That seemed to be a heavier design, though,
      and I'm
      not sure what the benefit would be.
      
      * The last, unused vestiges of # (unliftedTypeKind) have been removed.
      
      * There were several pretty-printing bugs that this change exposed;
      * these are fixed.
      
      * We previously checked for levity polymorphism in the types of binders.
      * But we
      also must exclude levity polymorphism in function arguments. This is
      hard to check
      for, requiring a good deal of care in the desugarer. See Note [Levity
      polymorphism
      checking] in DsMonad.
      
      * In order to efficiently check for levity polymorphism in functions, it
      * was necessary
      to add a new bit of IdInfo. See Note [Levity info] in IdInfo.
      
      * It is now safe for unlifted types to be unsaturated in Core. Core Lint
      * is updated
      accordingly.
      
      * We can only know strictness after zonking, so several checks around
      * strictness
      in the type-checker (checkStrictBinds, the check for unlifted variables
      under a ~
      pattern) have been moved to the desugarer.
      
      * Along the way, I improved the treatment of unlifted vs. banged
      * bindings. See
      Note [Strict binds checks] in DsBinds and #13075.
      
      * Now that we print type-checked source, we must be careful to print
      * ConLikes correctly.
      This is facilitated by a new HsConLikeOut constructor to HsExpr.
      Particularly troublesome
      are unlifted pattern synonyms that get an extra void# argument.
      
      * Includes a submodule update for haddock, getting rid of #.
      
      * New testcases:
        typecheck/should_fail/StrictBinds
        typecheck/should_fail/T12973
        typecheck/should_run/StrictPats
        typecheck/should_run/T12809
        typecheck/should_fail/T13105
        patsyn/should_fail/UnliftedPSBind
        typecheck/should_fail/LevPolyBounded
        typecheck/should_compile/T12987
        typecheck/should_compile/T11736
      
      * Fixed tickets:
        #12809
        #12973
        #11736
        #13075
        #12987
      
      * This also adds a test case for #13105. This test case is
      * "compile_fail" and
      succeeds, because I want the testsuite to monitor the error message.
      When #13105 is fixed, the test case will compile cleanly.
      e7985ed2
  6. 07 Jun, 2016 1 commit
  7. 22 May, 2016 1 commit
  8. 25 Feb, 2016 1 commit
    • barrucadu's avatar
      Print which warning-flag controls an emitted warning · bb5afd3c
      barrucadu authored
      Both gcc and clang tell which warning flag a reported warning can be
      controlled with, this patch makes ghc do the same. More generally, this
      allows for annotated compiler output, where an optional annotation is
      displayed in brackets after the severity.
      
      This also adds a new flag `-f(no-)show-warning-groups` to control
      whether to show which warning-group (such as `-Wall` or `-Wcompat`)
      a warning belongs to. This flag is on by default.
      
      This implements #10752
      
      Reviewed By: quchen, bgamari, hvr
      
      Differential Revision: https://phabricator.haskell.org/D1943
      bb5afd3c
  9. 08 Jan, 2016 1 commit
    • Simon Marlow's avatar
      Enable stack traces with ghci -fexternal-interpreter -prof · 6be09e88
      Simon Marlow authored
      Summary:
      The main goal here is enable stack traces in GHCi.  After this change,
      if you start GHCi like this:
      
        ghci -fexternal-interpreter -prof
      
      (which requires packages to be built for profiling, but not GHC
      itself) then the interpreter manages cost-centre stacks during
      execution and can produce a stack trace on request.  Call locations
      are available for all interpreted code, and any compiled code that was
      built with the `-fprof-auto` familiy of flags.
      
      There are a couple of ways to get a stack trace:
      
      * `error`/`undefined` automatically get one attached
      * `Debug.Trace.traceStack` can be used anywhere, and prints the current
        stack
      
      Because the interpreter is running in a separate process, only the
      interpreted code is running in profiled mode and the compiler itself
      isn't slowed down by profiling.
      
      The GHCi debugger still doesn't work with -fexternal-interpreter,
      although this patch gets it a step closer.  Most of the functionality
      of breakpoints is implemented, but the runtime value introspection is
      still not supported.
      
      Along the way I also did some refactoring and added type arguments to
      the various remote pointer types in `GHCi.RemotePtr`, so there's
      better type safety and documentation in the bridge code between GHC
      and ghc-iserv.
      
      Test Plan: validate
      
      Reviewers: bgamari, ezyang, austin, hvr, goldfire, erikd
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D1747
      
      GHC Trac Issues: #11047, #11100
      6be09e88
  10. 17 Dec, 2015 1 commit
    • Simon Marlow's avatar
      Remote GHCi, -fexternal-interpreter · 4905b83a
      Simon Marlow authored
      Summary:
      (Apologies for the size of this patch, I couldn't make a smaller one
      that was validate-clean and also made sense independently)
      
      (Some of this code is derived from GHCJS.)
      
      This commit adds support for running interpreted code (for GHCi and
      TemplateHaskell) in a separate process.  The functionality is
      experimental, so for now it is off by default and enabled by the flag
      -fexternal-interpreter.
      
      Reaosns we want this:
      
      * compiling Template Haskell code with -prof does not require
        building the code without -prof first
      
      * when GHC itself is profiled, it can interpret unprofiled code, and
        the same applies to dynamic linking.  We would no longer need to
        force -dynamic-too with TemplateHaskell, and we can load ordinary
        objects into a dynamically-linked GHCi (and vice versa).
      
      * An unprofiled GHCi can load and run profiled code, which means it
        can use the stack-trace functionality provided by profiling without
        taking the performance hit on the compiler that profiling would
        entail.
      
      Amongst other things; see
      https://ghc.haskell.org/trac/ghc/wiki/RemoteGHCi for more details.
      
      Notes on the implementation are in Note [Remote GHCi] in the new
      module compiler/ghci/GHCi.hs.  It probably needs more documenting,
      feel free to suggest things I could elaborate on.
      
      Things that are not currently implemented for -fexternal-interpreter:
      
      * The GHCi debugger
      * :set prog, :set args in GHCi
      * `recover` in Template Haskell
      * Redirecting stdin/stdout for the external process
      
      These are all doable, I just wanted to get to a working validate-clean
      patch first.
      
      I also haven't done any benchmarking yet.  I expect there to be slight hit
      to link times for byte code and some penalty due to having to
      serialize/deserialize TH syntax, but I don't expect it to be a serious
      problem.  There's also lots of low-hanging fruit in the byte code
      generator/linker that we could exploit to speed things up.
      
      Test Plan:
      * validate
      * I've run parts of the test suite with
      EXTRA_HC_OPTS=-fexternal-interpreter, notably tests/ghci and tests/th.
      There are a few failures due to the things not currently implemented
      (see above).
      
      Reviewers: simonpj, goldfire, ezyang, austin, alanz, hvr, niteria, bgamari, gibiansky, luite
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D1562
      4905b83a
  11. 11 Dec, 2015 1 commit
    • eir@cis.upenn.edu's avatar
      Add kind equalities to GHC. · 67465497
      eir@cis.upenn.edu authored
      This implements the ideas originally put forward in
      "System FC with Explicit Kind Equality" (ICFP'13).
      
      There are several noteworthy changes with this patch:
       * We now have casts in types. These change the kind
         of a type. See new constructor `CastTy`.
      
       * All types and all constructors can be promoted.
         This includes GADT constructors. GADT pattern matches
         take place in type family equations. In Core,
         types can now be applied to coercions via the
         `CoercionTy` constructor.
      
       * Coercions can now be heterogeneous, relating types
         of different kinds. A coercion proving `t1 :: k1 ~ t2 :: k2`
         proves both that `t1` and `t2` are the same and also that
         `k1` and `k2` are the same.
      
       * The `Coercion` type has been significantly enhanced.
         The documentation in `docs/core-spec/core-spec.pdf` reflects
         the new reality.
      
       * The type of `*` is now `*`. No more `BOX`.
      
       * Users can write explicit kind variables in their code,
         anywhere they can write type variables. For backward compatibility,
         automatic inference of kind-variable binding is still permitted.
      
       * The new extension `TypeInType` turns on the new user-facing
         features.
      
       * Type families and synonyms are now promoted to kinds. This causes
         trouble with parsing `*`, leading to the somewhat awkward new
         `HsAppsTy` constructor for `HsType`. This is dispatched with in
         the renamer, where the kind `*` can be told apart from a
         type-level multiplication operator. Without `-XTypeInType` the
         old behavior persists. With `-XTypeInType`, you need to import
         `Data.Kind` to get `*`, also known as `Type`.
      
       * The kind-checking algorithms in TcHsType have been significantly
         rewritten to allow for enhanced kinds.
      
       * The new features are still quite experimental and may be in flux.
      
       * TODO: Several open tickets: #11195, #11196, #11197, #11198, #11203.
      
       * TODO: Update user manual.
      
      Tickets addressed: #9017, #9173, #7961, #10524, #8566, #11142.
      Updates Haddock submodule.
      67465497
  12. 02 Jun, 2015 1 commit
  13. 01 Jun, 2015 1 commit
    • Simon Peyton Jones's avatar
      Refactor the GlobalRdrEnv, fixing #7672 · 9b73cb16
      Simon Peyton Jones authored
      This patch started innocently enough, by deleting a single
      call from rnImportDecl, namely
      
          let gbl_env = mkGlobalRdrEnv (filterOut from_this_mod gres)
      
      The 'filterOut' makes no sense, and was the cause of #7672.
      
      But that little loose end led to into a twisty maze of little
      passages, all alike, which has taken me an unreasonably long
      time to straighten out. Happily, I think the result is really
      much better.
      
      In particular:
      
       * INVARIANT 1 of the GlobalRdrEnv type was simply not true:
         we had multiple GlobalRdrElts in a list with the same
         gre_name field. This kludgily implmented one form of
         shadowing.
      
       * Meanwhile, extendGlobalRdrEnvRn implemented a second form of
         shadowing, by deleting stuff from the GlobalRdrEnv.
      
       * In turn, much of this shadowing stuff depended on the Names of
         the Ids bound in the GHCi InteractiveContext being Internal
         names, even though the TyCons and suchlike all had External
         Names. Very confusing.
      
      So I have made the following changes
      
       * I re-established INVARIANT 1 of GlobalRdrEnv.  As a result
         some strange code in RdrName.pickGREs goes away.
      
       * RnNames.extendGlobalRdrEnvRn now makes one call to deal with
         shadowing, where necessary, and another to extend the
         environment.  It deals separately with duplicate bindings.
      
         The very complicated RdrName.extendGlobalRdrEnv becomes much
         simpler; we need to export the shadowing function, now called
         RdrName.shadowNames; and we can nuke
         RdrName.findLocalDupsRdrEnv altogether.
      
         RdrName Note [GlobalRdrEnv shadowing] summarises the shadowing
         story
      
       * The Names of the Ids bound in the GHCi interactive context are
         now all External.  See Note [Interactively-bound Ids in GHCi]
         in HscTypes.
      
       * Names for Ids created by the debugger are now made by
         IfaceEnv.newInteractiveBinder.  This fixes a lurking bug which
         was that the debugger was using mkNewUniqueSupply 'I' to make
         uniques, which does NOT guarantee a fresh supply of uniques on
         successive calls.
      
       * Note [Template Haskell ambiguity] in RnEnv shows that one TH-related
         error is reported lazily (on occurrences) when it might be better
         reported when extending the environment.  In some (but not all) cases
         this was done before; but now it's uniformly at occurrences.  In
         some ways it'd be better to report when extending the environment,
         but it's a tiresome test and the error is rare, so I'm leaving it
         at the lookup site for now, with the above Note.
      
       * A small thing: RnNames.greAvail becomes RdrName.availFromGRE, where
         it joins the dual RdrName.gresFromAvail.
      9b73cb16
  14. 28 Jan, 2015 1 commit
  15. 17 Dec, 2014 1 commit
    • Simon Peyton Jones's avatar
      Fix GHCi/GHC-API tidying and modules (Trac #9424, #9426) · 67a0cab6
      Simon Peyton Jones authored
      There were two related bugs here
      
      Trac #9426
         We must increment the ic_mod_index field of the InteractiveContext
         if we have new instances, because we maek DFunIds that should be
         distinct from previous ones.  Previously we were only incrementing
         when defining new user-visible Ids.
      
         The main change is in HscTypes.extendInteractiveContext, which now
         alwyas bumps the ic_mod_index.  I also added a specialised
         extendInteractiveContextWithIds for the case where we are *only*
         adding new user-visible Ids.
      
      Trac #9424
         In HscMain.hscDeclsWithLocations we were failing to use the
         *tidied* ClsInsts; but the un-tidied ones are LocalIds which
         causes a later ASSERT error.
      
         On the way I realised that, to behave consistently, the tcg_insts
         and tcg_fam_insts field of TcGblEnv should really only contain
         instances from the current GHCi command, not all the ones to date.
         That in turn meant I had to move the code for deleting replacement
         instances from addLocalInst, addLocalFamInst to
         HscTypes.extendInteractiveContext
      67a0cab6
  16. 04 Nov, 2014 1 commit
  17. 28 Sep, 2014 1 commit
  18. 15 May, 2014 1 commit
    • Herbert Valerio Riedel's avatar
      Add LANGUAGE pragmas to compiler/ source files · 23892440
      Herbert Valerio Riedel authored
      In some cases, the layout of the LANGUAGE/OPTIONS_GHC lines has been
      reorganized, while following the convention, to
      
      - place `{-# LANGUAGE #-}` pragmas at the top of the source file, before
        any `{-# OPTIONS_GHC #-}`-lines.
      
      - Moreover, if the list of language extensions fit into a single
        `{-# LANGUAGE ... -#}`-line (shorter than 80 characters), keep it on one
        line. Otherwise split into `{-# LANGUAGE ... -#}`-lines for each
        individual language extension. In both cases, try to keep the
        enumeration alphabetically ordered.
        (The latter layout is preferable as it's more diff-friendly)
      
      While at it, this also replaces obsolete `{-# OPTIONS ... #-}` pragma
      occurences by `{-# OPTIONS_GHC ... #-}` pragmas.
      23892440
  19. 01 Oct, 2013 1 commit
    • unknown's avatar
      Improve pretty-printing of types · 66c5ddba
      unknown authored
      * The main change is to suppress printing (in types) of
           kind for-alls
           kind applications
        The new flag -fprint-explicit-kinds prints them as before
        (by analogy with the existing -fprint-explicit-foralls)
      
      * I also took advantage of the fact that SDoc now has access
        to DynFlags, to tidy up the way in which explicit for-alls
        are printed.  Instead of passing a boolean flag around, we
        now simply consult the DynFlags.  Much neater.
      
      I still need to add documentation for the flag
      66c5ddba
  20. 28 Jan, 2013 1 commit
    • Simon Peyton Jones's avatar
      Pure refactoring · f1fa6eb2
      Simon Peyton Jones authored
      * Move tidyType and friends from TcType to TypeRep
        (It was always wrong to have it in TcType.)
      
      * Move mkCoAxBranch and friends from FamInst to Coercion
      
      * Move pprCoAxBranch and friends from FamInstEnv to Coercion
      
      No change in functionality, though there might be a little
      wibble in error message output, because I combined two different
      functions both called pprCoAxBranch!
      f1fa6eb2
  21. 18 Oct, 2012 1 commit
    • ian@well-typed.com's avatar
      Refactor the way dump flags are handled · d4a19643
      ian@well-typed.com authored
      We were being inconsistent about how we tested whether dump flags
      were enabled; in particular, sometimes we also checked the verbosity,
      and sometimes we didn't.
      
      This lead to oddities such as "ghc -v4" printing an "Asm code" section
      which didn't contain any code, and "-v4" enabled some parts of
      "-ddump-deriv" but not others.
      
      Now all the tests use dopt, which also takes the verbosity into account
      as appropriate.
      d4a19643
  22. 16 Oct, 2012 2 commits
  23. 12 Jun, 2012 1 commit
  24. 11 Jun, 2012 1 commit
    • Ian Lynagh's avatar
      Pass DynFlags to the LogAction · 5716a2f8
      Ian Lynagh authored
      A side-effect is that we can no longer use the LogAction in
      defaultErrorHandler, as we don't have DynFlags at that point.
      But all that defaultErrorHandler did is to print Strings as
      SevFatal, so now it takes a 'FatalMessager' instead.
      5716a2f8
  25. 29 May, 2012 1 commit
  26. 21 Sep, 2011 2 commits
    • Simon Marlow's avatar
    • Simon Marlow's avatar
      Add support for all top-level declarations to GHCi · 3db75724
      Simon Marlow authored
        This is work mostly done by Daniel Winograd-Cort during his
        internship at MSR Cambridge, with some further refactoring by me.
      
      This commit adds support to GHCi for most top-level declarations that
      can be used in Haskell source files.  Class, data, newtype, type,
      instance are all supported, as are Type Family-related declarations.
      
      The current set of declarations are shown by :show bindings.  As with
      variable bindings, entities bound by newer declarations shadow earlier
      ones.
      
      Tests are in testsuite/tests/ghci/scripts/ghci039--ghci054.
      Documentation to follow.
      3db75724
  27. 25 Aug, 2011 1 commit
  28. 11 Jun, 2011 1 commit
    • Simon Peyton Jones's avatar
      Fix tracking of what RdrNames are used (fixes Trac #5211) · 6f60f1f5
      Simon Peyton Jones authored
      The issue here was: what import declaration brings into
      scope the 'op here
      
         import qualified Foo( op )
         import Bar( C(op) )
         instance C Int where
           op = ...
      
      Well, the import of Bar, obviously.  But what if the
      import Bar had been
         import Bar( C )
      Then the instance is still supposed to work, getting
      op from the Foo.op imported from Foo.  (I'm assuming its
      the same op, of course.)
      6f60f1f5
  29. 27 Oct, 2010 1 commit
    • Simon Marlow's avatar
      Refactoring and tidyup of HscMain and related things (also fix #1666) · 94bf0d36
      Simon Marlow authored
      While trying to fix #1666 (-Werror aborts too early) I decided to some
      tidyup in GHC/DriverPipeline/HscMain.
      
       - The GhcMonad overloading is gone from DriverPipeline and HscMain
         now.  GhcMonad is now defined in a module of its own, and only
         used in the top-level GHC layer.  DriverPipeline and HscMain
         use the plain IO monad and take HscEnv as an argument.
      
       - WarnLogMonad is gone.  printExceptionAndWarnings is now called
         printException (the old name is deprecated).  Session no longer
         contains warnings.
      
       - HscMain has its own little monad that collects warnings, and also
         plumbs HscEnv around.  The idea here is that warnings are collected
         while we're in HscMain, but on exit from HscMain (any function) we
         check for warnings and either print them (via log_action, so IDEs
         can still override the printing), or turn them into an error if
         -Werror is on.
      
       - GhcApiCallbacks is gone, along with GHC.loadWithLogger.  Thomas
         Schilling told me he wasn't using these, and I don't see a good
         reason to have them.
      
       - there's a new pure API to the parser (suggestion from Neil Mitchell):
            parser :: String
                   -> DynFlags
                   -> FilePath
                   -> Either ErrorMessages (WarningMessages, 
                                            Located (HsModule RdrName))
      94bf0d36
  30. 19 Oct, 2010 1 commit
    • simonpj@microsoft.com's avatar
      Clean up the debugger code · a40f2735
      simonpj@microsoft.com authored
      In particular there is much less fiddly skolemisation now
      Things are not *quite* right (break001 and 006 still fail), 
      but they are *much* better than before.
      a40f2735
  31. 06 Jul, 2009 1 commit
  32. 01 Jul, 2009 1 commit
  33. 02 Jan, 2009 1 commit
    • simonpj@microsoft.com's avatar
      Make record selectors into ordinary functions · 9ffadf21
      simonpj@microsoft.com authored
      This biggish patch addresses Trac #2670.  The main effect is to make
      record selectors into ordinary functions, whose unfoldings appear in
      interface files, in contrast to their previous existence as magic
      "implicit Ids".  This means that the usual machinery of optimisation,
      analysis, and inlining applies to them, which was failing before when
      the selector was somewhat complicated.  (Which it can be when
      strictness annotations, unboxing annotations, and GADTs are involved.)
      
      The change involves the following points
      
      * Changes in Var.lhs to the representation of Var.  Now a LocalId can
        have an IdDetails as well as a GlobalId.  In particular, the
        information that an Id is a record selector is kept in the
        IdDetails.  While compiling the current module, the record selector
        *must* be a LocalId, so that it participates properly in compilation
        (free variables etc).
      
        This led me to change the (hidden) representation of Var, so that there
        is now only one constructor for Id, not two.
      
      * The IdDetails is persisted into interface files, so that an
        importing module can see which Ids are records selectors.
      
      * In TcTyClDecls, we generate the record-selector bindings in renamed,
        but not typechecked form.  In this way, we can get the typechecker
        to add all the types and so on, which is jolly helpful especially
        when GADTs or type families are involved.  Just like derived
        instance declarations.
      
        This is the big new chunk of 180 lines of code (much of which is
        commentary).  A call to the same function, mkAuxBinds, is needed in
        TcInstDcls for associated types.
      
      * The typechecker therefore has to pin the correct IdDetails on to 
        the record selector, when it typechecks it.  There was a neat way
        to do this, by adding a new sort of signature to HsBinds.Sig, namely
        IdSig.  This contains an Id (with the correct Name, Type, and IdDetails);
        the type checker uses it as the binder for the final binding.  This
        worked out rather easily.
      
      * Record selectors are no longer "implicit ids", which entails changes to
           IfaceSyn.ifaceDeclSubBndrs
           HscTypes.implicitTyThings
           TidyPgm.getImplicitBinds
        (These three functions must agree.)
      
      * MkId.mkRecordSelectorId is deleted entirely, some 300+ lines (incl
        comments) of very error prone code.  Happy days.
      
      * A TyCon no longer contains the list of record selectors: 
        algTcSelIds is gone
      
      The renamer is unaffected, including the way that import and export of
      record selectors is handled.
      
      Other small things
      
      * IfaceSyn.ifaceDeclSubBndrs had a fragile test for whether a data
        constructor had a wrapper.  I've replaced that with an explicit flag
        in the interface file. More robust I hope.
      
      * I renamed isIdVar to isId, which touched a few otherwise-unrelated files.
      
      9ffadf21
  34. 18 Sep, 2008 1 commit
    • pepe's avatar
      Fix a couple of issues with :print · decbb181
      pepe authored
            
            - Ticket #1995: Unsoundness with newtypes
            - Ticket #2475: "Can't unify" error when stopped at an exception
            
            In addition this patch adds the following:
            
            - Unfailingness: RTTI cannot panic anymore. 
              In case of failure, it recovers gracefully by returning the "I know nothing" type
            - A -ddump-rtti flag
      decbb181
  35. 15 Sep, 2008 1 commit
  36. 31 Jul, 2008 1 commit
  37. 30 Jul, 2008 1 commit
  38. 21 Apr, 2008 1 commit