May 2017 - ghc-tickets

[GHC] #13659: Bug report: "AThing evaluated unexpectedly tcTyVar a_alF"
by GHC 09 May '17

09 May '17

#13659: Bug report: "AThing evaluated unexpectedly tcTyVar a_alF" -------------------------------------+------------------------------------- Reporter: costaparas | Owner: (none) Type: bug | Status: new Priority: highest | Milestone: Component: Compiler | Version: 8.0.1 Keywords: | Operating System: Linux Architecture: x86_64 | Type of failure: Compile-time (amd64) | performance bug Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- The following code: {{{#!hs {-# LANGUAGE GADTs, EmptyDataDecls, TypeFamilies, TypeOperators, DataKinds, FlexibleInstances #-} {- Defines a C-like printf function using DataKinds extensions. -} module Printf where -- format string parameterized by a list of types data Format (fmt :: [*]) where X :: Format '[] -- empty string, i.e. "" L :: a -> String -> Format '[] -- string literal, e.g. "hello" S :: a -> Format '[String] -- "%s" I :: Format a -> Format '[Int, a] -- "%d" }}} produces the following error: GHCi, version 7.10.3: http://www.haskell.org/ghc/ :? for help [1 of 1] Compiling Printf ( Printf.hs, interpreted ) a.hs:12:27:ghc: panic! (the 'impossible' happened) (GHC version 7.10.3 for x86_64-unknown-linux): AThing evaluated unexpectedly tcTyVar a_alF Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug when run using **ghci Printf.hs** on Liunx Ubuntu 16.04 LTS 64-bit with Intel® Core™ i7-7500U CPU @ 2.70GHz -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13659> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #13646: strict patterns with no bindings (e.g. `let !() = ...`) trigger -Wunused-pattern-binds
by GHC 09 May '17

09 May '17

#13646: strict patterns with no bindings (e.g. `let !() = ...`) trigger -Wunused- pattern-binds -------------------------------------+------------------------------------- Reporter: exphp | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.2 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: -------------------------------------+------------------------------------- In each of the following programs, a bang pattern is used to force evaluation of a bottom, the intent being to perform fail-fast error checking. Unfortunately, however, they also generate `-Wunused-pattern- binds`. {{{#!hs {-# OPTIONS_GHC -Wall #-} {-# LANGUAGE BangPatterns #-} main :: IO () main = do let !Nothing = Just () pure () }}} {{{#!hs {-# OPTIONS_GHC -Wall #-} {-# LANGUAGE BangPatterns #-} import Control.Exception main :: IO () main = do let !() = assert False () pure () }}} {{{ src/Lib.hs:6:9: warning: [-Wunused-pattern-binds] This pattern-binding binds no variables: !Nothing = Just () Linking src/Lib ... Lib: src/Lib.hs:6:9-26: Irrefutable pattern failed for pattern Nothing -------------------- src/Lib.hs:8:9: warning: [-Wunused-pattern-binds] This pattern-binding binds no variables: !() = assert False () Linking src/Lib ... Lib: Assertion failed CallStack (from HasCallStack): assert, called at src/Lib.hs:8:15 in main:Main }}} For clarity, non-monadic `let ... in` patterns are also affected; I only gloss over them because there tends to be other equally ergonomic alternatives in such cases. I found this #9127 (ticket), where a patch was accepted to allow wildcards of the form `!_`. However, `!_` is unsatisfactory and perhaps even dangerous for such usage, as it does not constrain the type in any manner. In particular, there is nothing to prevent somebody from writing {{{#!hs main = do let !_ = assert someCondition -- (missing an argument) pure () }}} which //is// in fact useless. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13646> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #8332: hp2ps does not escape parentheses
by GHC 09 May '17

09 May '17

#8332: hp2ps does not escape parentheses ------------------------------------+------------------------------------- Reporter: luite | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Profiling | Version: 7.7 Keywords: | Operating System: Unknown/Multiple Architecture: Unknown/Multiple | Type of failure: None/Unknown Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | ------------------------------------+------------------------------------- If some symbol name in the key includes a (, but is cut off before the ), hp2ps generates an invalid postscript file. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8332> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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Re: [GHC] #4820: "Invalid object in isRetainer" when doing retainer profiling in GHC 7 branch
by GHC 09 May '17

09 May '17

#4820: "Invalid object in isRetainer" when doing retainer profiling in GHC 7 branch ----------------------------------+-------------------------------------- Reporter: dleuschner | Owner: (none) Type: bug | Status: infoneeded Priority: highest | Milestone: 8.4.1 Component: Profiling | Version: 8.0.1 Resolution: | Keywords: Operating System: MacOS X | Architecture: x86_64 (amd64) Type of failure: Runtime crash | Test Case: Blocked By: | Blocking: Related Tickets: #11978 | Differential Rev(s): Wiki Page: | ----------------------------------+-------------------------------------- Changes (by bgamari): * milestone: 8.2.1 => 8.4.1 Comment: Bumping off to 8.4. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/4820#comment:12> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #13211: NegativeLiterals -0.0 :: Double
by GHC 09 May '17

09 May '17

#13211: NegativeLiterals -0.0 :: Double -------------------------------------+------------------------------------- Reporter: rwbarton | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.1 Keywords: newcomer | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Compare {{{ rwbarton@morphism:~$ ghc-8.0.1 -e '-0.0' -0.0 rwbarton@morphism:~$ ghc-8.0.1 -XNegativeLiterals -e '-0.0' 0.0 }}} This behavior is logical, but unexpected. The logic is that with `NegativeLiterals` the literal `-0.0` means `fromRational ((-0)%0)`, which equals `fromRational 0`, which for `Double` is positive zero, not negative zero. But this seems unfortunate. Perhaps it would be best if `-0.0` (or `-` applied to any other literal mathematically equal to zero) was desugared as `negate 0.0` even under `NegativeLiterals`, since there doesn't seem to be any other reason to write `-0.0`. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13211> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #13667: Error while running stack upgrade
by GHC 08 May '17

08 May '17

#13667: Error while running stack upgrade ----------------------------------------+--------------------------------- Reporter: diego.saa | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Keywords: stack ghc | Operating System: MacOS X Architecture: Unknown/Multiple | Type of failure: None/Unknown Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: ----------------------------------------+--------------------------------- $ stack upgrade Fetching package index ...remote: Counting objects: 11, done. remote: Compressing objects: 100% (8/8), done. remote: Total 11 (delta 3), reused 11 (delta 3), pack-reused 0 Unpacking objects: 100% (11/11), done. From https://github.com/commercialhaskell/all-cabal-hashes t [tag update] current-hackage -> current-hackage Fetched package index. Populated index cache. aeson-1.0.2.1: configure aeson-1.0.2.1: build ed25519-0.0.5.0: configure ed25519-0.0.5.0: build optparse-applicative-0.13.0.0: configure optparse-applicative-0.13.0.0: build pid1-0.1.0.0: configure pid1-0.1.0.0: build cryptohash-sha256-0.11.100.1: configure cryptohash-sha256-0.11.100.1: build store-core-0.3: configure pid1-0.1.0.0: copy/register store-core-0.3: build http-client-0.5.3.3: configure cryptohash-sha256-0.11.100.1: copy/register http-client-0.5.3.3: build Cabal-1.24.2.0: configure ed25519-0.0.5.0: copy/register Cabal-1.24.2.0: build text-metrics-0.1.0: configure store-core-0.3: copy/register text-metrics-0.1.0: build th-orphans-0.13.1: configure th-orphans-0.13.1: build text-metrics-0.1.0: copy/register optparse-applicative-0.13.0.0: copy/register th-orphans-0.13.1: copy/register optparse-simple-0.0.3: configure optparse-simple-0.0.3: build th-utilities-0.2.0.1: configure th-utilities-0.2.0.1: build optparse-simple-0.0.3: copy/register http-client-0.5.3.3: copy/register http-client-tls-0.3.4: configure th-utilities-0.2.0.1: copy/register http-client-tls-0.3.4: build store-0.3: configure store-0.3: build http-client-tls-0.3.4: copy/register store-0.3: copy/register aeson-1.0.2.1: copy/register http-conduit-2.2.3: configure http-conduit-2.2.3: build aeson-compat-0.3.6: configure aeson-compat-0.3.6: build persistent-2.6: configure persistent-2.6: build yaml-0.8.20: configure yaml-0.8.20: build binary-tagged-0.1.4.1: configure http-conduit-2.2.3: copy/register aeson-compat-0.3.6: copy/register binary-tagged-0.1.4.1: build path-0.5.9: configure path-0.5.9: build path-0.5.9: copy/register path-io-1.1.0: configure path-io-1.1.0: build binary-tagged-0.1.4.1: copy/register path-io-1.1.0: copy/register yaml-0.8.20: copy/register hpack-0.17.0: configure hpack-0.17.0: build persistent-2.6: copy/register persistent-template-2.5.1.6: configure persistent-template-2.5.1.6: build persistent-sqlite-2.6: configure persistent-sqlite-2.6: build hpack-0.17.0: copy/register Cabal-1.24.2.0: copy/register hackage-security-0.5.2.2: configure hackage-security-0.5.2.2: build persistent-template-2.5.1.6: copy/register hackage-security-0.5.2.2: copy/register persistent-sqlite-2.6: copy/register stack-1.4.0: configure [1 of 1] Compiling Main ( /private/var/folders/6w/t3g51rsj29xc0gdw5fd9j_4h0000gn/T/stack- upgrade4642/stack-1.4.0/Setup.hs, /private/var/folders/6w/t3g51rsj29xc0gdw5fd9j_4h0000gn/T/stack- upgrade4642/stack-1.4.0/.stack- work/dist/x86_64-osx/Cabal-1.22.5.0/setup/Main.o ) Linking /private/var/folders/6w/t3g51rsj29xc0gdw5fd9j_4h0000gn/T/stack- upgrade4642/stack-1.4.0/.stack- work/dist/x86_64-osx/Cabal-1.22.5.0/setup/setup ... Configuring stack-1.4.0... stack-1.4.0: build Preprocessing library stack-1.4.0... [ 1 of 124] Compiling Text.PrettyPrint.Leijen.Extended ( src/Text/PrettyPrint/Leijen/Extended.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Text/PrettyPrint/Leijen/Extended.o ) [ 2 of 124] Compiling Hackage.Security.Client.Repository.HttpLib.HttpClient ( src/Hackage/Security/Client/Repository/HttpLib/HttpClient.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Hackage/Security/Client/Repository/HttpLib/HttpClient.o ) [ 3 of 124] Compiling Stack.Options.ScriptParser ( src/Stack/Options/ScriptParser.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Stack/Options/ScriptParser.o ) [ 4 of 124] Compiling Stack.Ghci.Script ( src/Stack/Ghci/Script.hs, .stack-work/dist/x86_64-osx/Cabal-1.22.5.0/build/Stack/Ghci/Script.o ) [ 5 of 124] Compiling Stack.FileWatch ( src/Stack/FileWatch.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Stack/FileWatch.o ) [ 6 of 124] Compiling System.Process.PagerEditor ( src/System/Process/PagerEditor.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/System/Process/PagerEditor.o ) [ 7 of 124] Compiling System.Process.Log ( src/System/Process/Log.hs, .stack-work/dist/x86_64-osx/Cabal-1.22.5.0/build/System/Process/Log.o ) [ 8 of 124] Compiling Paths_stack ( .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/autogen/Paths_stack.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Paths_stack.o ) [ 9 of 124] Compiling Path.Find ( src/Path/Find.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Path/Find.o ) [ 10 of 124] Compiling Path.Extra ( src/Path/Extra.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Path/Extra.o ) [ 11 of 124] Compiling System.Process.Read ( src/System/Process/Read.hs, .stack-work/dist/x86_64-osx/Cabal-1.22.5.0/build/System/Process/Read.o ) ghc: panic! (the 'impossible' happened) (GHC version 7.10.3 for x86_64-apple-darwin): Loading temp shared object failed: dlopen(/var/folders/6w/t3g51rsj29xc0gdw5fd9j_4h0000gn/T/ghc7414_0/libghc_68.dylib, 5): no suitable image found. Did find: /var/folders/6w/t3g51rsj29xc0gdw5fd9j_4h0000gn/T/ghc7414_0/libghc_68.dylib: malformed mach-o: load commands size (49000) > 32768 Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug Completed 26 action(s). -- While building package stack-1.4.0 using: /private/var/folders/6w/t3g51rsj29xc0gdw5fd9j_4h0000gn/T/stack- upgrade4642/stack-1.4.0/.stack- work/dist/x86_64-osx/Cabal-1.22.5.0/setup/setup --builddir=.stack- work/dist/x86_64-osx/Cabal-1.22.5.0 build lib:stack exe:stack --ghc- options " -ddump-hi -ddump-to-file" Process exited with code: ExitFailure 1 MBPs-MacBook-Pro:~ mbp$ ghc --version The Glorious Glasgow Haskell Compilation System, version 8.0.1 -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13667> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #13665: Broken Link in GHC Docs for Custom compile-time errors
by GHC 08 May '17

08 May '17

#13665: Broken Link in GHC Docs for Custom compile-time errors -------------------------------------+------------------------------------- Reporter: atwupack | Owner: (none) Type: bug | Status: new Priority: low | Milestone: Component: Documentation | Version: 8.2.1-rc1 Keywords: | Operating System: Other Architecture: Other | Type of failure: Documentation | bug Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Hello, in the GHC documentation for custom compile-time errors is a link to the GHC.TypeLits module which is broken. It points to GHC.TypeList instead of GHC.TypeLits. This is the case for 8.0.1, 8.0.2 and 8.2.1-rc1 as far as I have checked. URL: https://downloads.haskell.org/~ghc/8.2.1-rc1/docs/html/users_guide/glasgow_… #custom-compile-time-errors André -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13665> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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Re: [GHC] #2168: ghci should show haddock comments for identifier
by GHC 08 May '17

08 May '17

#2168: ghci should show haddock comments for identifier -------------------------------------+------------------------------------- Reporter: j.waldmann | Owner: (none) Type: feature request | Status: new Priority: normal | Milestone: Component: GHCi | Version: 6.8.2 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: | -------------------------------------+------------------------------------- Changes (by ntc2): * cc: ntc2 (added) -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/2168#comment:29> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #13575: GHC downloads do not work
by GHC 08 May '17

08 May '17

#13575: GHC downloads do not work -------------------------------------+------------------------------------- Reporter: sergv | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: None | Version: 8.0.2 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: Installing GHC Unknown/Multiple | failed Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- I'm not sure whether this is the right place for this type of issue, but I cannot download GHC 8.0.2 for i386 debian 8 (http://downloads.haskell.org/~ghc/8.0.2/ghc-8.0.2-i386-deb8-linux.tar.xz) - I get 404 Not Found error from nginx. I tried from 2 different IPs, so the issue is likely not on my side. I tried some other urls and they all result in the same 404 error: * http://downloads.haskell.org/~ghc/8.0.2/ghc-8.0.2-armv7-deb8-linux.tar.xz * http://downloads.haskell.org/~ghc/8.0.2/ghc-8.0.2-x86_64-centos67-linux.tar… * http://downloads.haskell.org/~ghc/8.0.2/ghc-8.0.2-x86_64-unknown- openbsd.tar.xz * http://downloads.haskell.org/~ghc/8.0.2/ghc-8.0.2-x86_64-deb8-linux.tar.xz * http://downloads.haskell.org/~ghc/8.0.2/ghc-8.0.2-src.tar.xz -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13575> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #13663: Option to disable turning recursive let-bindings to recursive functions
by GHC 08 May '17

08 May '17

#13663: Option to disable turning recursive let-bindings to recursive functions -------------------------------------+------------------------------------- Reporter: darchon | Owner: (none) Type: feature | Status: new request | 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: -------------------------------------+------------------------------------- First some context: I'm using the GHC API to convert Haskell to digital circuit descriptions (clash compiler). When viewed as a structural description of a circuit, recursive let- bindings can be turned into feedback loops. In general, when viewed as a structural description of a circuit, recursive functions describe infinite hierarchy, i.e. they are not realisable as circuit. So now my problem: the simplifier turns recursive let-bindings to recursive functions; i.e. it is turning something which I can translate to a circuit to something which I cannot translate to a circuit. Next follows a reduced test case which exemplifies this behaviour: {{{#!haskell module Test where import Control.Applicative topEntity :: [((),())] topEntity = (,) <$> outport1 <*> outport2 where (outport1, outResp1) = gpio (decodeReq 1 req) (outport2, outResp2) = gpio (decodeReq 2 req) ramResp = ram (decodeReq 0 req) req = core $ (<|>) <$> ramResp <*> ((<|>) <$> outResp1 <*> outResp2) core :: [Maybe ()] -> [()] core = fmap (maybe () id) {-# NOINLINE core #-} ram :: [()] -> [Maybe ()] ram = fmap pure {-# NOINLINE ram #-} decodeReq :: Integer -> [()] -> [()] decodeReq 0 = fmap (const ()) decodeReq 1 = id decodeReq _ = fmap id {-# NOINLINE decodeReq #-} gpio :: [()] -> ([()],[Maybe ()]) gpio i = (i,pure <$> i) {-# NOINLINE gpio #-} }}} Now, when we look at the output of the desugarer (-ddump-ds), we can see that the core-level binder of `topEntity` basically follows the Haskell code. {{{#!haskell topEntity :: [((), ())] [LclIdX] topEntity = letrec { ds_d2rI :: ([()], [Maybe ()]) [LclId] ds_d2rI = gpio (decodeReq 1 req_a2pF); ds_d2rS :: ([()], [Maybe ()]) [LclId] ds_d2rS = gpio (decodeReq 2 req_a2pF); req_a2pF [Occ=LoopBreaker] :: [()] [LclId] req_a2pF = $ @ 'GHC.Types.LiftedRep @ [Maybe ()] @ [()] core (<*> @ [] GHC.Base.$fApplicative[] @ (Maybe ()) @ (Maybe ()) (<$> @ [] @ (Maybe ()) @ (Maybe () -> Maybe ()) GHC.Base.$fFunctor[] (<|> @ Maybe GHC.Base.$fAlternativeMaybe @ ()) (ram (decodeReq 0 req_a2pF))) (<*> @ [] GHC.Base.$fApplicative[] @ (Maybe ()) @ (Maybe ()) (<$> @ [] @ (Maybe ()) @ (Maybe () -> Maybe ()) GHC.Base.$fFunctor[] (<|> @ Maybe GHC.Base.$fAlternativeMaybe @ ()) (case ds_d2rI of { (_ [Occ=Dead], outResp1_X2pQ) -> outResp1_X2pQ })) (case ds_d2rS of { (_ [Occ=Dead], outResp2_X2q2) -> outResp2_X2q2 }))); } in <*> @ [] GHC.Base.$fApplicative[] @ () @ ((), ()) (<$> @ [] @ () @ (() -> ((), ())) GHC.Base.$fFunctor[] (GHC.Tuple.(,) @ () @ ()) (case ds_d2rI of { (outport1_a2pA, _ [Occ=Dead]) -> outport1_a2pA })) (case ds_d2rS of { (outport2_a2pM, _ [Occ=Dead]) -> outport2_a2pM }) }}} However, when we look at the simplifier output, with nearly all transformations disabled (-O0 -ddump-ds), you will see that parts of `topEntity` are split into 3 different top-level, mutually recursive, functions. {{{#!haskell Rec { ds_r2so :: ([()], [Maybe ()]) ds_r2so = gpio (decodeReq 1 req_r2sq) -- RHS size: {terms: 4, types: 0, coercions: 0, joins: 0/0} ds1_r2sp :: ([()], [Maybe ()]) ds1_r2sp = gpio (decodeReq 2 req_r2sq) req_r2sq :: [()] req_r2sq = core (<*> @ [] GHC.Base.$fApplicative[] @ (Maybe ()) @ (Maybe ()) (<$> @ [] @ (Maybe ()) @ (Maybe () -> Maybe ()) GHC.Base.$fFunctor[] (<|> @ Maybe GHC.Base.$fAlternativeMaybe @ ()) (ram (decodeReq 0 req_r2sq))) (<*> @ [] GHC.Base.$fApplicative[] @ (Maybe ()) @ (Maybe ()) (<$> @ [] @ (Maybe ()) @ (Maybe () -> Maybe ()) GHC.Base.$fFunctor[] (<|> @ Maybe GHC.Base.$fAlternativeMaybe @ ()) (case ds_r2so of { (outport1_a2pA, outResp1_X2pQ) -> outResp1_X2pQ })) (case ds1_r2sp of { (outport2_a2pM, outResp2_X2q2) -> outResp2_X2q2 }))) end Rec } topEntity :: [((), ())] topEntity = <*> @ [] GHC.Base.$fApplicative[] @ () @ ((), ()) (<$> @ [] @ () @ (() -> ((), ())) GHC.Base.$fFunctor[] (GHC.Tuple.(,) @ () @ ()) (case ds_r2so of { (outport1_a2pA, outResp1_X2pQ) -> outport1_a2pA })) (case ds1_r2sp of { (outport2_a2pM, outResp2_X2q2) -> outport2_a2pM }) }}} So my question are: - Which part of the simplifier is turning these local recursive let- binders into global recursive functions? - Is there some way to disable this transformation? - If not, how much effort do you think it would be to put this behaviour behind a dynflag? So that I, as a GHC API user, can disable it for my use- case. I'm willing to implements this dynflag myself. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13663> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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