January 2016 - ghc-tickets

[GHC] #8652: Cross-compiling broken for ARM/Linux target
by GHC 07 Jan '16

07 Jan '16

#8652: Cross-compiling broken for ARM/Linux target ----------------------------+---------------------------------------- Reporter: kgardas | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.7 Keywords: | Operating System: Linux Architecture: arm | Type of failure: Building GHC failed Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | ----------------------------+---------------------------------------- I've attempted to cross compile GHC HEAD on Ubuntu 13.10 with ubuntu's hard-float tool-chain and LLVM. I've configured GHC with: {{{ $ ./configure --target=arm-linux-gnueabihf }}} and compiling by make works till it fails with: {{{ inplace/bin/deriveConstants --gen-header -o includes/dist- derivedconstants/header/DerivedConstants.h --tmpdir includes/dist- derivedconstants/header/ --gcc-program "/usr/bin/gcc" --gcc-flag -fno- stack-protector --gcc-flag -Iincludes --gcc-flag -Iincludes/dist --gcc- flag -Iincludes/dist-derivedconstants/header --gcc-flag -Iincludes/dist- ghcconstants/header --gcc-flag -Irts --gcc-flag -fcommon --nm-program "/usr/bin/arm-linux-gnueabihf-nm" /usr/bin/arm-linux-gnueabihf-nm: includes/dist- derivedconstants/header/tmp.o: File format not recognized deriveConstants: readProcess: /usr/bin/arm-linux-gnueabihf-nm "includes /dist-derivedconstants/header/tmp.o" (exit 1): failed make[1]: *** [includes/dist-derivedconstants/header/DerivedConstants.h] Error 1 }}} As a workaround for this issue, it's possible to use --with-gcc= and this way deriveConstants gets the right cross GCC. Looks like a bug somewhere in make machinery or configure itself. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8652> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 3

[GHC] #11190: Hello "schedule: re-entered unsafely."
by GHC 07 Jan '16

07 Jan '16

#11190: Hello "schedule: re-entered unsafely." --------------------------------+---------------------------------- Reporter: Chobbes | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.10.2 Keywords: | Operating System: Linux Architecture: arm | Type of failure: Runtime crash Test Case: | Blocked By: Blocking: | Related Tickets: 951 Differential Rev(s): | Wiki Page: --------------------------------+---------------------------------- After compiling the following program on ARM: {{{#!hs main = putStrLn "Hello, world!" }}} using `ghc hello.hs` I receive the following error when running the compiled code: {{{ $ ./hello hello: schedule: re-entered unsafely. Perhaps a 'foreign import unsafe' should be 'safe'? }}} I'm trying to get GHC running on my Raspberry Pi 2, running Raspbian Jessie Light, which can be found here: https://www.raspberrypi.org/downloads/raspbian/ I was following the instructions for installing the compiler on a freshly flashed RPI2 from here: http://statusfailed.com/blog/2015/11/29/haskell-and-servant-on-scaleway- arm-servers.html This was using the Linux ARMv7 binaries: https://www.haskell.org/ghc/download_ghc_7_10_3#linux_armv7 https://www.haskell.org/ghc/download_ghc_7_10_2#linux_armv7 Additionally trying to upgrade cabal with `cabal install cabal-install` seems to hang forever. It gets stuck in various Setup.hs files and doesn't seem to progress. No CPU is taken up using this. Some summary information: - llvm 3.5 - gcc 4.9.2 - original GHC from Raspbian is 7.6.3 - cabal-install from Raspbian is 1.20.0.3 - cabal is 1.20.0.2 - This same problem affects both 7.10.2, and 7.10.3 -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11190> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 6

[GHC] #11049: Allow CallStacks to be hidden or cut
by GHC 07 Jan '16

07 Jan '16

#11049: Allow CallStacks to be hidden or cut -------------------------------------+------------------------------------- Reporter: nomeata | Owner: Type: feature | Status: new request | Priority: normal | Milestone: Component: Compiler | Version: 7.10.2 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: #11035 Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- This is a spin off of #11035. I’d like to see a way for a function `foo` * use another function `bar` with a `(?_::CallStack)` constraint so that `bar` will _not_ print a call stack, and * use another function `bar` with a `(?_::CallStack)` constraint so that if `bar` prints a call stack, it will stop at the call to `foo`. This might be possible to implement with a special `rootCallStack :: CallStack` which is a value such that {{{ x `pushCallStack` rootCallStack = rootCallStack }}} but {{{ rootCallStack `pushCallStack` x = rootCallStack “:” x }}} as before and a call stack that consists of only a rootCallStack causes no stack trace to be printed. The use case is to provide the user of a library less cluttered call stacks that do not expose unhelpful details and allow her to quickly spot the relevant information. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11049> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 11

[GHC] #10464: ghc 7.8.4 on arm
by GHC 07 Jan '16

07 Jan '16

#10464: ghc 7.8.4 on arm -------------------------------------+------------------------------------- Reporter: | Owner: andrewufrank | Status: new Type: bug | Milestone: Priority: normal | Version: 7.8.4 Component: Compiler | Operating System: Linux Keywords: | Type of failure: Compile-time Architecture: arm | performance bug Test Case: | Blocked By: Blocking: | Related Tickets: Differential Revisions: | -------------------------------------+------------------------------------- when compiling i get the warning /usr/bin/d.gold: warning: cannot scan executable section 1 of ..... transformers-04.3.0a... for Cortex-A8 erratum because it has no mapping symbols. there are some informations on the web on the cortex-a8 erratum, but i cannot see how i could apply them. should the compiler be recompiled? i installed from the debian distribution. the hardware is a cubietruck. i observe that compilation, especially the phase of preparing the configuration in cabal takes very long - perhaps this is related to this problem. the resulting code is ok and runs with expected speed. thank you for producing a full ghc for arm! andrew -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10464> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 9

Re: [GHC] #1168: Optimisation sometimes decreases sharing in IO code
by GHC 07 Jan '16

07 Jan '16

#1168: Optimisation sometimes decreases sharing in IO code -------------------------------------+------------------------------------- Reporter: simonmar | Owner: Type: bug | Status: new Priority: normal | Milestone: ⊥ Component: Compiler | Version: 6.6 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: | nofib/spectral/calendar Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by nomeata): See #11365 for another example, it seems. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/1168#comment:20> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 0

[GHC] #10625: Spurious unused quantified type variable warning with ExistentialQuantification
by GHC 07 Jan '16

07 Jan '16

#10625: Spurious unused quantified type variable warning with ExistentialQuantification -------------------------------------+------------------------------------- Reporter: | Owner: RyanGlScott | Status: new Type: bug | Milestone: Priority: normal | Version: 7.10.1 Component: Compiler | Operating System: Unknown/Multiple Keywords: | Type of failure: Incorrect Architecture: | warning at compile-time Unknown/Multiple | Blocked By: Test Case: | Related Tickets: #5331 Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- When using an existentially quantified type variable that shadows another variable in a data declaration, {{{-Wall}}} produces more warnings than necessary: {{{ $ ghci -XExistentialQuantification -Wall GHCi, version 7.10.1: http://www.haskell.org/ghc/ :? for help λ> data Ex a = forall a. Ex a <interactive>:2:20: Warning: Unused quantified type variable ‘a’ In the definition of data constructor ‘Ex’ <interactive>:2:20: Warning: This binding for ‘a’ shadows the existing binding bound at <interactive>:2:9 }}} The unused quantified type variable warning seems wrong, since it ''is'' being used (as the shadowing warning indicates). Curiously, this warning doesn't seem to appear when doing something similar with {{{RankNTypes}}}: {{{ $ ghci -XRankNTypes -Wall GHCi, version 7.10.1: http://www.haskell.org/ghc/ :? for help λ> data Ex a = Ex (forall a. a) <interactive>:2:24: Warning: This binding for ‘a’ shadows the existing binding bound at <interactive>:2:9 }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10625> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 4

[GHC] #11366: Control.Exception.assert should perhaps take an implicit call stack
by GHC 06 Jan '16

06 Jan '16

#11366: Control.Exception.assert should perhaps take an implicit call stack -------------------------------------+------------------------------------- Reporter: bgamari | Owner: Type: task | Status: new Priority: normal | Milestone: 8.0.1 Component: Compiler | Version: 7.10.3 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: -------------------------------------+------------------------------------- It seems to me like our new implicit parameters-based callstack support is a more principled way of accomplishing the ad-hoc rewriting that we current do for `assert`. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11366> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 2

[GHC] Batch modify: #10137, #10788, #10677
by GHC 06 Jan '16

06 Jan '16

Batch modification to #10137, #10788, #10677 by thomie: milestone to 8.0.1 Action: leave -- Tickets URL: <http://ghc.haskell.org/trac/ghc/query?id=10137%2C10788%2C10677> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 0

Re: [GHC] #4437: unregistered language extensions
by GHC 06 Jan '16

06 Jan '16

#4437: unregistered language extensions -------------------------------------+--------------------------------- Reporter: duncan | Owner: Type: bug | Status: closed Priority: normal | Milestone: Component: Compiler | Version: Resolution: fixed | Keywords: Operating System: Unknown/Multiple | Architecture: Unknown/Multiple Type of failure: None/Unknown | Test Case: T4437 Blocked By: | Blocking: -------------------------------------+--------------------------------- Comment (by Ben Gamari <ben@…>): In [changeset:"7861a22561846eef9a6415a93d79e121dca9c05f/ghc" 7861a225/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="7861a22561846eef9a6415a93d79e121dca9c05f" Add a note describing the protocol for adding a language extension Reviewers: hvr, thomie, austin Reviewed By: austin Subscribers: duncan Differential Revision: https://phabricator.haskell.org/D1741 GHC Trac Issues: #8176, #4437 }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/4437#comment:3> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 0

Re: [GHC] #2496: Invalid Eq/Ord instances in Data.Version
by GHC 06 Jan '16

06 Jan '16

#2496: Invalid Eq/Ord instances in Data.Version -------------------------------------+------------------------------------- Reporter: guest | Owner: Type: bug | Status: new Priority: normal | Milestone: 8.2.1 Component: Core Libraries | Version: 6.8.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D395 Wiki Page: | -------------------------------------+------------------------------------- Comment (by bgamari): It would be great if at least this particular item could make it on to that list. In general it would be great to have a comprehensive summary of the committee's future plans. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/2496#comment:29> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 0