May 2017 - ghc-tickets

[GHC] #13649: RebindableSyntax causes type errors when 'fail' is not defined, even if not used.
by GHC 15 May '17

15 May '17

#13649: RebindableSyntax causes type errors when 'fail' is not defined, even if not used. -------------------------------------+------------------------------------- Reporter: AaronFriel | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.2.1-rc1 Keywords: | Operating System: Unknown/Multiple RebindableSyntax | Architecture: | Type of failure: GHC rejects Unknown/Multiple | valid program Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- With -XRebindableSyntax and a wildcard pattern on an action, a spurious compiler error occurs if `fail` is not in scope: {{{ Not in scope: ‘fail’ Perhaps you want to add ‘fail’ to the import list in the import of ‘Prelude’ (rebind.hs:6:1-53). | 27 | _ <- m1 | ^^^^^^^ }}} {{{#!hs {-# LANGUAGE NoImplicitPrelude #-} {-# LANGUAGE RebindableSyntax #-} module Main where import Prelude (String, print, Maybe (..), error, id) class MyFunctor f where fmap :: (a -> b) -> f a -> f b class MyApplicative f where pure :: a -> f a (<*>) :: f (a -> b) -> f a -> f b class MyMonad m where return :: a -> m a (>>) :: m a -> m b -> m b (>>=) :: m a -> (a -> m b) -> m b join :: m (m a) -> m a -- Uncommenting the following lines allows testCase1 to compile: -- class MyFail m where -- fail :: String -> m a -- But testCase1 will not require a 'MyFail m' constraint. testCase1 :: MyMonad m => m a -> m () testCase1 m1 = do _ <- m1 return () testCase2 :: MyMonad m => m a -> m () testCase2 m1 = do m1 return () }}} In this example, testCase1 will fail to compile until the type class `MyFail` is uncommented. As with #13648, I think this looks like an easy fix before the 8.2.1 release, and I would be happy to submit a patch next week if someone could point me the way. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13649> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #13473: Variables in patterns made with QuasiQuotes sometimes don't get bound
by GHC 15 May '17

15 May '17

#13473: Variables in patterns made with QuasiQuotes sometimes don't get bound -------------------------------------+------------------------------------- Reporter: harpocrates | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.2 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: GHC rejects Unknown/Multiple | valid program Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- In GHCi 8.0.2 {{{ >>> import Language.Haskell.TH >>> import Language.Haskell.TH.Quote >>> :set -XQuasiQuotes >>> quoter = QuasiQuoter { quotePat = varP . mkName } >>> [quoter|x|] = 1 >>> x error: Variable not in scope: x }}} I think "x" ought to be 1. Previous versions of GHCi don't let me be so free about defining and using quasiquotes, so here is a minimal example with modules: {{{ -- In QQ.hs module QQ where import Language.Haskell.TH import Language.Haskell.TH.Quote quoter :: QuasiQuoter quoter = QuasiQuoter { quotePat = varP . mkName } }}} and {{{ -- In Main1.hs module Main1 where import QQ [quoter|x|] = 1 main = print x }}} With GHC 7.10.3 this compiles (and prints "1" when run), but in GHC 8.0.2 this complains "x" is not in scope. The same problem manifests itself when the pattern quasi quote is used in a "let" binding. Peculiarly, this appears ''not'' to affect cases where the pattern is a function argument. The following compiles and runs (printing "1") on both 7.10.3 and 8.0.2. {{{ -- In Main2.hs module Main2 where import QQ f [quoter|x|] = x main = print (f 1) }}} I understand there were some changes around splices and declaration groups (which presumably are part of why GHCi plays with quasi quotes), so I'm not sure this is really a bug! -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13473> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #13591: "*** Exception: expectJust showModule" in ghci with hs-boot
by GHC 15 May '17

15 May '17

#13591: "*** Exception: expectJust showModule" in ghci with hs-boot -------------------------------------+------------------------------------- Reporter: lspitzner | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: GHCi | Version: 8.2.1-rc1 Keywords: ghci hs-boot | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- ghci runs into an exception if there is an error in Foo.hs when there exists a Foo.hs-boot (which compiles fine). - First.hs-boot {{{ module First where one :: Int }}} - Second.hs {{{ module Second where import {-# SOURCE #-} First two :: Int two = one + 1 }}} - First.hs {{{ module First where import Second one :: Int one = _ }}} {{{ > ghci Prelude> :l First [1 of 3] Compiling First[boot] ( First.hs-boot, interpreted ) [2 of 3] Compiling Second ( Second.hs, interpreted ) [3 of 3] Compiling First ( First.hs, interpreted ) First.hs:6:7: error: • Found hole: _ :: Int • In the expression: _ In an equation for ‘one’: one = _ • Relevant bindings include one :: Int (bound at First.hs:6:1) *** Exception: expectJust showModule CallStack (from HasCallStack): error, called at compiler/utils/Maybes.hs:48:27 in ghc:Maybes }}} This happens on ghc-8.0.1, 8.0.2 and 8.2.1-rc1. The above output is from 8.0.2, but the error seems to be essentially the same on 8.2.1-rc1. It did not happen on 7.10.3. While ghci continues to work, the exception appears to clear the loaded- modules list, which in turn breaks tooling (ghcid here, which hangs as a consequence). The expected behaviour would be that other modules (which contain no errors) remain loaded. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13591> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #13658: Assertion failure on HEAD: "optCoercion changed types!"
by GHC 15 May '17

15 May '17

#13658: Assertion failure on HEAD: "optCoercion changed types!" -------------------------------------+------------------------------------- Reporter: bgamari | Owner: (none) Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler | Version: 8.3 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- I am seeing the following assertion failure on my `wip/libdw-prof` branch, {{{ ghc-stage1: panic! (the 'impossible' happened) (GHC version 8.3.20170507 for x86_64-unknown-linux): ASSERT failed! optCoercion changed types! in_co: (base:Data.Typeable.Internal.TypeRep{tc 35W} (UnsafeCo nominal ghc-prim:GHC.Types.Any{(w) tc 35K} (ghc- prim:GHC.Types.Any{(w) tc 35K} -> ghc- prim:GHC.Types.Any{(w) tc 35K})) (UnsafeCo nominal (ghc-prim:GHC.Types.Any{(w) tc 35K} ghc-prim:GHC.Types.Any{(w) tc 35K}) ghc- prim:GHC.Types.Any{(w) tc 35K}))_R in_ty1: base:Data.Typeable.Internal.TypeRep{tc 35W} (ghc-prim:GHC.Types.Any{(w) tc 35K} ghc-prim:GHC.Types.Any{(w) tc 35K}) in_ty2: base:Data.Typeable.Internal.TypeRep{tc 35W} ghc-prim:GHC.Types.Any{(w) tc 35K} out_co: (base:Data.Typeable.Internal.TypeRep{tc 35W} (UnsafeCo nominal ghc-prim:GHC.Types.Any{(w) tc 35K} (ghc- prim:GHC.Types.Any{(w) tc 35K} -> ghc- prim:GHC.Types.Any{(w) tc 35K})) <ghc-prim:GHC.Types.Any{(w) tc 35K}>_N)_R out_ty1: base:Data.Typeable.Internal.TypeRep{tc 35W} ghc-prim:GHC.Types.Any{(w) tc 35K} out_ty2: 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lvl_s5uo{v} lvl_s5up{v} lvl_s5uq{v} lvl_s5ur{v} lvl_s5us{v} lvl_s5ut{v} lvl_s5uu{v} lvl_s5uv{v} $dTypeable_s5uK{v} lvl_s5uU{v} lvl_s5v8{v} lvl_s5v9{v} lvl_s5va{v} lvl_s5vb{v} lvl_s5vc{v} lvl_s5vg{v} lvl_s5wZ{v} kind_vars_s5x2{v} lvl_s5xf{v} $j_s5Da{v} lvl_s5Mo{v} lvl_s5Mp{v} lvl_s5Mq{v} lvl_s5Mr{v} lvl_s5Ms{v} kind_vars_s5MF{v} kind_vars_s5MG{v} lvl_s5MI{v} modl_s5Nw{v} lvl_s5OE{v} $wrnfModule{v s6s3} $wrnfTyCon{v s6sj} $wgo{v s6tn} $wtypeSymbolTypeRep{v s6uf} lvl_s6Qv{v} lvl_s6Qw{v} lvl_s6Qx{v} lvl_s6Qy{v} lvl_s6Qz{v} lvl_s6QA{v} lvl_s6QB{v} lvl_s6QC{v} lvl_s6QD{v} lvl_s6QF{v} lvl_s6QG{v} lvl_s6QI{v} lvl_s6QJ{v} lvl_s6QK{v} lvl_s6QL{v} lvl_s6QM{v} lvl_s6QN{v} lvl_s6QO{v} lvl_s6QP{v} lvl_s6QQ{v} lvl_s6QR{v} lvl_s6QS{v} lvl_s6QT{v} lvl_s6QU{v} lvl_s6QV{v} lvl_s6QW{v} lvl_s6QY{v} lvl_s6QZ{v} lvl_s6R0{v} lvl_s6R1{v} lvl_s6R2{v} lvl_s6Rb{v} lvl_s6Rd{v} lvl_s6Re{v} lvl_s6Rf{v} lvl_s6Rg{v} lvl_s6Rh{v} lvl_s6Ri{v} lvl_s6Rj{v} lvl_s6Rk{v} lvl_s6Rl{v} lvl_s6Rm{v} lvl_s6Rn{v} lvl_s6Ro{v} lvl_s6Rp{v} lvl_s6Rq{v} lvl_s6Rr{v} lvl_s6Rs{v} lvl_s6Rt{v} lvl_s6Ru{v} lvl_s6Rv{v} lvl_s6Rw{v} lvl_s6Rx{v} lvl_s6Ry{v} lvl_s6Rz{v} lvl_s6RA{v} lvl_s6RC{v} lvl_s6RD{v} lvl_s6RE{v} lvl_s6RG{v} lvl_s6RL{v} lvl_s6RM{v} lvl_s6RN{v} lvl_s6RO{v} lvl_s6RP{v} lvl_s6RQ{v} lvl_s6RR{v} lvl_s6RS{v} lvl_s6RT{v} lvl_s6RU{v} lvl_s6RV{v} lvl_s6RW{v} lvl_s6RX{v} lvl_s6RY{v} lvl_s6RZ{v} lvl_s6S0{v} lvl_s6S1{v} lvl_s6S2{v} lvl_s6S3{v} lvl_s6S4{v} lvl_s6S5{v} lvl_s6S6{v} lvl_s6S7{v} lvl_s6S8{v} lvl_s6S9{v} lvl_s6Sa{v} lvl_s6Sb{v} lvl_s6Sc{v} lvl_s6Sd{v} lvl_s6Se{v} lvl_s6Sf{v} lvl_s6Sg{v} lvl_s6Sh{v} lvl_s6Si{v} lvl_s6Sj{v} lvl_s6Sl{v} lvl_s6Sm{v} lvl_s6So{v} lvl_s6Sp{v} lvl_s6Sr{v} lvl_s6Ss{v} lvl_s6Su{v} lvl_s6Sv{v} lvl_s6Sx{v} lvl_s6Sy{v} lvl_s6SA{v} lvl_s6SB{v} lvl_s6SD{v} lvl_s6SE{v} lvl_s6SG{v} lvl_s6SH{v} lvl_s6SJ{v} lvl_s6SK{v} go{v s6SM} go{v s6SO} lvl_s6SR{v} wild_s6ST{v} ds_s6SU{v} ds_s6SV{v} ds_s6SW{v} ds_s6SX{v} nKindVars#{v s6SY} kindRep{v s6SZ} lvl_s6T8{v} lvl_s6Ta{v} $sgo{v s7lX} sc_s7lY{v} sc_s7lZ{v} sc_s7m0{v} sc_s7m1{v} sc_s7m3{v} sc_s7m5{v} $sgo{v s7m6} $s$wgo{v s7sR} $s$wgo{v s7sV} $stypeRepTyCon{v s7th} $stypeRepTyCon{v s7ti} $stypeRepTyCon{v s7tj} $srnfList{v s7tW}} Type env: [a403 :-> (a{tv a403} [tv] :: (k{tv a402} [tv] :: *)), a43r :-> (k1{tv a43r} [tv] :: (k{tv a43q} [tv] :: *)), a43t :-> (a{tv a43t} [tv] :: (k{tv a43s} [tv] :: *))] Co env: []] }}} This is with the following `build.mk`, {{{#!makefile BuildFlavour = dwarf ifneq "$(BuildFlavour)" "" include mk/flavours/$(BuildFlavour).mk endif GhcStage2HcOpts += -eventlog STRIP_CMD = : }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13658> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #13697: Teach GHCi to deduplicate history
by GHC 15 May '17

15 May '17

#13697: Teach GHCi to deduplicate history -------------------------------------+------------------------------------- Reporter: bgamari | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- GHCi's (or rather, Haskeline's) history functionality tends to duplicate entries, even when the user used history to enter an entry. This is quite annoying and an issue I've not noticed in other command line libraries. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13697> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #13692: Constructors and such should be able to move around seq# sometimes
by GHC 15 May '17

15 May '17

#13692: Constructors and such should be able to move around seq# sometimes -------------------------------------+------------------------------------- Reporter: dfeuer | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.4.1 Component: Compiler | Version: 8.2.1-rc2 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: Runtime Unknown/Multiple | performance bug Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- This code {{{#!hs module SeqCon where import Control.Exception (evaluate) blah :: Int -> IO Int blah x = (+2) <$> evaluate (x + 3) }}} compiled with `-O2 -ddump-prep -dsuppress-coercions` produces the following (and `-ddump-stg` doesn't change much of note): {{{ SeqCon.blah1 :: GHC.Types.Int -> GHC.Prim.State# GHC.Prim.RealWorld -> (# GHC.Prim.State# GHC.Prim.RealWorld, GHC.Types.Int #) [GblId, Arity=2, Caf=NoCafRefs, Str=<L,1*U(U)><S,U>, Unf=OtherCon []] SeqCon.blah1 = \ (x_s1cz [Occ=Once!] :: GHC.Types.Int) (s_s1cA [Occ=Once] :: GHC.Prim.State# GHC.Prim.RealWorld) -> let { sat_s1cE [Occ=Once] :: GHC.Types.Int [LclId] sat_s1cE = case x_s1cz of { GHC.Types.I# x1_s1cC [Occ=Once] -> case GHC.Prim.+# x1_s1cC 3# of sat_s1cD { __DEFAULT -> GHC.Types.I# sat_s1cD } } } in case GHC.Prim.seq# @ GHC.Types.Int @ GHC.Prim.RealWorld sat_s1cE s_s1cA of { (# ipv_s1cG [Occ=Once], ipv1_s1cH [Occ=Once!] #) -> let { sat_s1cL [Occ=Once] :: GHC.Types.Int [LclId] sat_s1cL = case ipv1_s1cH of { GHC.Types.I# x1_s1cJ [Occ=Once] -> case GHC.Prim.+# x1_s1cJ 2# of sat_s1cK { __DEFAULT -> GHC.Types.I# sat_s1cK } } } in (# ipv_s1cG, sat_s1cL #) } -- RHS size: {terms: 5, types: 3, coercions: 5, joins: 0/0} SeqCon.blah :: GHC.Types.Int -> GHC.Types.IO GHC.Types.Int [GblId, Arity=2, Caf=NoCafRefs, Str=<L,1*U(U)><S,U>, Unf=OtherCon []] SeqCon.blah = (\ (eta_B2 [Occ=Once] :: GHC.Types.Int) (eta_B1 [Occ=Once] :: GHC.Prim.State# GHC.Prim.RealWorld) -> SeqCon.blah1 eta_B2 eta_B1) `cast` <Co:5> }}} This builds a closure to build an `Int` and passes it to `seq#`. That seems a bit wasteful, since we don't actually need the `Int` box. I think what we'd really like to end up with is something like {{{#!hs blah1 = \ (x :: Int) (s :: State# RealWorld) -> case seq# x s of { (# s', x' #) -> case x' of { I# x# -> (# s', I# (x# +# 5#) #) }} }}} Here's one vague idea: when we analyse `x+3` (the argument to `seq#`) under a strict demand, we see it is strict in `x`. So we can transform `seq# (x + 3) s` into {{{#!hs case seq# x s of (# s', x' #) -> seq# (x' + 3) s' }}} We know that `x'` is in WHNF, so we should (I think) be able to see that `x' + 3` isn't bottom, so we can use {{{#!hs case seq# x s of {(# s', x' #) -> case x' + 3 of {!res -> s', res}} }}} Side note: the redundant eta-expansion in `blah` is a bit surprising. `blah1` already has arity 2, so I'd have expected `blah` to just coerce it directly. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13692> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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Re: [GHC] #1600: Optimisation: CPR the results of IO
by GHC 15 May '17

15 May '17

#1600: Optimisation: CPR the results of IO -------------------------------------+------------------------------------- Reporter: simonmar | Owner: (none) Type: task | Status: new Priority: lowest | Milestone: Component: Compiler | Version: 6.6.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Runtime | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: #8598 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by akio): simonpj: I've added two examples that use IO. After a bit of work I managed to make a big improvement on `x2n1`: {{{ -------------------------------------------------------------------------------- Program Size Allocs Runtime Elapsed TotalMem -------------------------------------------------------------------------------- bspt -0.1% +0.1% 0.007 0.007 0.0% cacheprof -0.1% +0.1% +28.4% +28.4% +0.9% grep -0.1% -0.2% 0.000 0.000 0.0% maillist -0.1% -0.3% 0.053 0.053 0.0% hpg -0.1% -0.4% 0.205 0.205 0.0% pic -0.1% -0.6% 0.007 0.007 0.0% compress2 +0.2% -0.9% 0.196 0.196 -19.2% infer -0.1% -1.2% 0.069 0.069 0.0% sphere -0.1% -1.7% 0.049 0.049 0.0% solid -0.1% -6.6% 0.127 0.169 0.0% x2n1 -0.1% -84.7% 0.006 0.006 0.0% -------------------------------------------------------------------------------- Min -0.1% -84.7% -37.7% -35.7% -19.2% Max +0.2% +0.1% +34.3% +34.2% +0.9% Geometric Mean -0.1% -1.9% -2.6% -1.3% -0.2% }}} I wonder if this improvement justifies the added complexity to the compiler (about 400 lines of code added under `compiler/`). Right now I don't see any way to make the analysis/transformation more effective. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/1600#comment:73> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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Re: [GHC] #7897: MakeTypeRep fingerprints be proper, robust fingerprints
by GHC 14 May '17

14 May '17

#7897: MakeTypeRep fingerprints be proper, robust fingerprints -------------------------------------+------------------------------------- Reporter: simonpj | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: ⊥ Component: Compiler | Version: 7.6.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by bgamari): We don't currently offer a way to view the runtime representation of a type at runtime (other than I suppose `Generic`). That being said, we do generate Typeable evidence for promoted data constructors, so we already do much of the work necessary to do so. That being said, it's not clear that this would be a useful enough feature to justify the cost. As far as making the hash more precise is concerned, the data family issue is enough of am argument against rocking the boat without very good reason. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7897#comment:7> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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Re: [GHC] #7897: MakeTypeRep fingerprints be proper, robust fingerprints
by GHC 14 May '17

14 May '17

#7897: MakeTypeRep fingerprints be proper, robust fingerprints -------------------------------------+------------------------------------- Reporter: simonpj | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: ⊥ Component: Compiler | Version: 7.6.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by cdupont): I have a real use case for this bug in Hint: https://github.com/mvdan/hint/issues/31 Having proper fingerprints would allow to check the run time type representation and prevent the segfault. Is there a workaround? How to check the structure of a type at run-time? -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7897#comment:6> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #13696: rts/linker/ElfTypes.h does not compile on most of UNREG arches (and some registerised arches)
by GHC 14 May '17

14 May '17

#13696: rts/linker/ElfTypes.h does not compile on most of UNREG arches (and some registerised arches) -------------------------------------+------------------------------------- Reporter: slyfox | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Builds fail as: {{{ rts_dist_HC rts/dist/build/RtsStartup.o rts/linker/ElfTypes.h:23:4: error: error: #error "Unsupported arch!" }}} The code that fails in '''rts/linker/ElfTypes.h''': {{{#!c # define ELF_TARGET_AMD64 /* Used inside <elf.h> on Solaris 11 */ #if defined(powerpc64_HOST_ARCH) || defined(powerpc64le_HOST_ARCH) \ || defined(ia64_HOST_ARCH) || defined(aarch64_HOST_ARCH) \ || defined(x86_64_HOST_ARCH) # define ELF_64BIT #elif defined(sparc_HOST_ARCH) || defined(i386_HOST_ARCH) \ || defined(arm_HOST_ARCH) # define ELF_32BIT #else # error "Unsupported arch!" #endif }}} Note it's a whitelist of architectures. It fails at least on '''powerpc''' (arm_HOST_ARCH), '''hppa'' (hppa_HOST_ARCH), '''m68k''' (m68k_HOST_ARCH). '''mips''', '''mips64''', '''alpha''', '''s390x''', '''sparc64'''. It does not look like keeping a whitelist is scalable here. How about using {{{#!c #if defined(__LP64__) || defined (_LP64) }}} as a proxy for ELF64 and maintain a list of arches that are exception instead? -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13696> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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