March 2015 - ghc-tickets

[GHC] #9988: Remove fun_id, is_infix from FunBind, as they are now in Match
by GHC 11 Nov '15

11 Nov '15

#9988: Remove fun_id, is_infix from FunBind, as they are now in Match -------------------------------------+------------------------------------- Reporter: alanz | Owner: Type: task | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.10.1-rc1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Blocked By: Test Case: | Related Tickets: Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- One of the changes Phab:D538 introduced is to add m_fun_id_infix to Match {{{#!hs data Match id body = Match { m_fun_id_infix :: (Maybe (Located id,Bool)), -- fun_id and fun_infix for functions with multiple equations -- only present for a RdrName. See note [fun_id in Match] m_pats :: [LPat id], -- The patterns m_type :: (Maybe (LHsType id)), -- A type signature for the result of the match -- Nothing after typechecking m_grhss :: (GRHSs id body) } deriving (Typeable) }}} This was done to track the individual locations and fixity of the fun_id for each of the defining equations for a function when there are more than one. For example, the function (&&&) is defined with some prefix and some infix equations below. {{{#!hs (&&& ) [] [] = [] xs &&& [] = xs ( &&& ) [] ys = ys }}} This means that the fun_id / is_infix is now superfluous in the FunBind. This has not been removed as a potentially risky change just before 7.10 RC2, and so must be done after. This ticket captures that task. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9988> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #9591: Add custom "Wiki" field in Trac
by GHC 06 Nov '15

06 Nov '15

#9591: Add custom "Wiki" field in Trac -------------------------------------+------------------------------------- Reporter: jstolarek | Owner: hvr Type: feature request | Status: new Priority: normal | Milestone: Component: Trac & Git | Version: Keywords: | Operating System: Architecture: Unknown/Multiple | Unknown/Multiple Difficulty: Unknown | Type of failure: Blocked By: | None/Unknown Related Tickets: | Test Case: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- I want to request a new custom field to Trac called "Wiki page"? Tickets that are about implementing a larger feature have an accompanying wiki page that summarizes the design. It would help my workflow if I could just get to that wiki page from the top of a Trac ticket. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9591> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #9297: Packages linked against certain Windows .dll files give warnings at runtime
by GHC 22 Oct '15

22 Oct '15

#9297: Packages linked against certain Windows .dll files give warnings at runtime ----------------------------------+--------------------------------- Reporter: RyanGlScott | Owner: simonmar Type: bug | Status: new Priority: normal | Milestone: Component: Runtime System | Version: 7.8.2 Keywords: | Operating System: Windows Architecture: x86_64 (amd64) | Type of failure: None/Unknown Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | ----------------------------------+--------------------------------- I am using GHC 7.8.3 on Windows 7, x86_64. When GHC loads certain packages at runtime, it gives some interesting warnings: {{{ > ghci -package haskeline GHCi, version 7.8.3: http://www.haskell.org/ghc/ :? for help Loading package ghc-prim ... linking ... done. Loading package integer-gmp ... linking ... done. Loading package base ... linking ... done. Loading package array-0.5.0.0 ... linking ... done. Loading package deepseq-1.3.0.2 ... linking ... done. Loading package bytestring-0.10.4.0 ... linking ... done. Loading package Win32-2.3.0.2 ... linking ... done. Loading package containers-0.5.5.1 ... linking ... done. Loading package filepath-1.3.0.2 ... linking ... done. Loading package old-locale-1.0.0.6 ... linking ... done. Loading package time-1.4.2 ... linking ... done. Loading package directory-1.2.1.0 ... linking ... done. Loading package transformers-0.3.0.0 ... linking ... done. Loading package haskeline-0.7.1.2 ... linking ... ghc.exe: warning: SetConsoleCursorPosition from kernel32 is linked instead of __imp_SetConsoleCursorPosition ghc.exe: warning: FillConsoleOutputCharacterA from kernel32 is linked instead of __imp_FillConsoleOutputCharacterA ghc.exe: warning: FillConsoleOutputAttribute from kernel32 is linked instead of __imp_FillConsoleOutputAttribute done. Prelude> }}} Besides {{{haskeline}}}, other packages with similar problems include {{{unix-compat}}}, {{{network}}}, and {{{regex-posix}}}. To see them all at once, you can run the [{{{hermit-web}}} https://github.com/ku-fpg /hermit-web] executable: {{{ > hermit-web Last.hs [starting HERMIT-Web v0.1.0.0 on Last.hs] [starting HERMIT v0.5.0.0 on Last.hs] % ghc Last.hs -fforce-recomp -O2 -dcore-lint -fsimple-list-literals -fexpose-all-unfoldings -fplugin=HERMIT.Web -fplugin-opt=HERMIT.Web:*: [1 of 1] Compiling Main ( Last.hs, Last.o ) Loading package ghc-prim ... linking ... done. Loading package integer-gmp ... linking ... done. Loading package base ... linking ... done. Loading package array-0.5.0.0 ... linking ... done. Loading package deepseq-1.3.0.2 ... linking ... done. Loading package bytestring-0.10.4.0 ... linking ... done. Loading package containers-0.5.5.1 ... linking ... done. Loading package Win32-2.3.0.2 ... linking ... done. Loading package filepath-1.3.0.2 ... linking ... done. Loading package old-locale-1.0.0.6 ... linking ... done. Loading package time-1.4.2 ... linking ... done. Loading package directory-1.2.1.0 ... linking ... done. Loading package pretty-1.1.1.1 ... linking ... done. Loading package process-1.2.0.0 ... linking ... done. Loading package Cabal-1.18.1.3 ... linking ... done. Loading package binary-0.7.1.0 ... linking ... done. Loading package bin-package-db-0.0.0.0 ... linking ... done. Loading package hoopl-3.10.0.1 ... linking ... done. Loading package hpc-0.6.0.1 ... linking ... done. Loading package template-haskell ... linking ... done. Loading package transformers-0.3.0.0 ... linking ... done. Loading package ghc-7.8.3 ... linking ... done. Loading package haskeline-0.7.1.2 ... linking ... ghc: warning: SetConsoleCursorPosition from kernel32 is linked instead of __imp_SetConsoleCursorPosition ghc: warning: FillConsoleOutputCharacterA from kernel32 is linked instead of __imp_FillConsoleOutputCharacterA ghc: warning: FillConsoleOutputAttribute from kernel32 is linked instead of __imp_FillConsoleOutputAttribute done. Loading package text-1.1.1.3 ... linking ... done. Loading package hashable-1.2.2.0 ... linking ... done. Loading package scientific-0.3.2.2 ... linking ... done. Loading package attoparsec-0.12.1.0 ... linking ... done. Loading package dlist-0.7.1 ... linking ... done. Loading package mtl-2.1.3.1 ... linking ... done. Loading package syb-0.4.2 ... linking ... done. Loading package unordered-containers-0.2.5.0 ... linking ... done. Loading package primitive-0.5.3.0 ... linking ... done. Loading package vector-0.10.11.0 ... linking ... done. Loading package aeson-0.7.0.6 ... linking ... done. Loading package blaze-builder-0.3.3.2 ... linking ... done. Loading package data-default-class-0.0.1 ... linking ... done. Loading package data-default-instances-base-0.0.1 ... linking ... done. Loading package data-default-instances-containers-0.0.1 ... linking ... done. Loading package data-default-instances-dlist-0.0.1 ... linking ... done. Loading package data-default-instances-old-locale-0.0.1 ... linking ... done. Loading package data-default-0.5.3 ... linking ... done. Loading package ansi-terminal-0.6.1.1 ... linking ... done. Loading package kure-2.16.2 ... linking ... done. Loading package marked-pretty-0.1 ... linking ... done. Loading package random-1.0.1.1 ... linking ... done. Loading package operational-0.2.3.2 ... linking ... done. Loading package stm-2.4.3 ... linking ... done. Loading package exceptions-0.6.1 ... linking ... done. Loading package temporary-1.2.0.3 ... linking ... done. Loading package hermit-0.5.0.0 ... linking ... done. Loading package case-insensitive-1.2.0.0 ... linking ... done. Loading package http-types-0.8.5 ... linking ... done. Loading package transformers-base-0.4.2 ... linking ... done. Loading package monad-control-0.3.3.0 ... linking ... done. Loading package lifted-base-0.2.3.0 ... linking ... done. Loading package mmorph-1.0.3 ... linking ... done. Loading package resourcet-1.1.2.2 ... linking ... done. Loading package nats-0.2 ... linking ... done. Loading package semigroups-0.15.1 ... linking ... done. Loading package void-0.6.1 ... linking ... done. Loading package conduit-1.1.6 ... linking ... done. Loading package regex-base-0.93.2 ... linking ... done. Loading package regex-posix-0.95.2 ... linking ... ghc: warning: isupper from msvcrt is linked instead of __imp_isupper ghc: warning: toupper from msvcrt is linked instead of __imp_toupper ghc: warning: tolower from msvcrt is linked instead of __imp_tolower ghc: warning: isalpha from msvcrt is linked instead of __imp_isalpha ghc: warning: isalpha from msvcrt is linked instead of __imp_isalpha ghc: warning: isalpha from msvcrt is linked instead of __imp_isalpha ghc: warning: iscntrl from msvcrt is linked instead of __imp_iscntrl ghc: warning: isupper from msvcrt is linked instead of __imp_isupper ghc: warning: isgraph from msvcrt is linked instead of __imp_isgraph ghc: warning: isprint from msvcrt is linked instead of __imp_isprint ghc: warning: ispunct from msvcrt is linked instead of __imp_ispunct ghc: warning: isalnum from msvcrt is linked instead of __imp_isalnum ghc: warning: isalpha from msvcrt is linked instead of __imp_isalpha ghc: warning: isalnum from msvcrt is linked instead of __imp_isalnum ghc: warning: isalnum from msvcrt is linked instead of __imp_isalnum ghc: warning: isalnum from msvcrt is linked instead of __imp_isalnum ghc: warning: isalnum from msvcrt is linked instead of __imp_isalnum ghc: warning: isalnum from msvcrt is linked instead of __imp_isalnum ghc: warning: isalnum from msvcrt is linked instead of __imp_isalnum ghc: warning: isalnum from msvcrt is linked instead of __imp_isalnum ghc: warning: isalnum from msvcrt is linked instead of __imp_isalnum ghc: warning: isalnum from msvcrt is linked instead of __imp_isalnum ghc: warning: isalnum from msvcrt is linked instead of __imp_isalnum ghc: warning: isalnum from msvcrt is linked instead of __imp_isalnum ghc: warning: isalnum from msvcrt is linked instead of __imp_isalnum done. Loading package regex-compat-0.95.1 ... linking ... done. Loading package parsec-3.1.5 ... linking ... done. Loading package network-2.5.0.0 ... linking ... ghc: warning: WSACleanup from ws2_32 is linked instead of __imp_WSACleanup ghc: warning: WSAStartup from ws2_32 is linked instead of __imp_WSAStartup ghc: warning: WSACleanup from ws2_32 is linked instead of __imp_WSACleanup ghc: warning: accept from ws2_32 is linked instead of __imp_accept ghc: warning: inet_ntoa from ws2_32 is linked instead of __imp_inet_ntoa ghc: warning: getnameinfo from ws2_32 is linked instead of __imp_getnameinfo ghc: warning: getaddrinfo from ws2_32 is linked instead of __imp_getaddrinfo ghc: warning: freeaddrinfo from ws2_32 is linked instead of __imp_freeaddrinfo done. Loading package vault-0.3.0.3 ... linking ... done. Loading package wai-3.0.0.2 ... linking ... done. Loading package base64-bytestring-1.0.0.1 ... linking ... done. Loading package fast-logger-2.1.5 ... linking ... done. Loading package zlib-0.5.4.1 ... linking ... done. Loading package streaming-commons-0.1.3.1 ... linking ... done. Loading package stringsearch-0.3.6.5 ... linking ... done. Loading package byteorder-1.0.4 ... linking ... done. Loading package wai-logger-2.1.1 ... linking ... done. Loading package word8-0.0.4 ... linking ... done. Loading package wai-extra-3.0.1 ... linking ... done. Loading package conduit-extra-1.1.1 ... linking ... done. Loading package simple-sendfile-0.2.15 ... linking ... done. Loading package unix-compat-0.4.1.3 ... linking ... ghc: warning: GetVersionExA from kernel32 is linked instead of __imp_GetVersionExA ghc: warning: GetModuleHandleA from kernel32 is linked instead of __imp_GetModuleHandleA ghc: warning: GetProcAddress from kernel32 is linked instead of __imp_GetProcAddress ghc: warning: _snprintf from msvcrt is linked instead of __imp__snprintf ghc: warning: GetSystemInfo from kernel32 is linked instead of __imp_GetSystemInfo ghc: warning: GetSystemMetrics from user32 is linked instead of __imp_GetSystemMetrics ghc: warning: GetVersionExA from kernel32 is linked instead of __imp_GetVersionExA ghc: warning: _snprintf from msvcrt is linked instead of __imp__snprintf ghc: warning: GetSystemInfo from kernel32 is linked instead of __imp_GetSystemInfo ghc: warning: GetComputerNameA from kernel32 is linked instead of __imp_GetComputerNameA ghc: warning: CryptAcquireContextA from advapi32 is linked instead of __imp_CryptAcquireContextA ghc: warning: CryptGenRandom from advapi32 is linked instead of __imp_CryptGenRandom ghc: warning: _stat64 from msvcrt is linked instead of __imp__stat64 ghc: warning: _open from msvcrt is linked instead of __imp__open ghc: warning: _stat64 from msvcrt is linked instead of __imp__stat64 done. Loading package warp-3.0.0.4 ... linking ... done. Loading package scotty-0.8.1 ... linking ... done. Loading package hermit-web-0.1.0.0 ... linking ... done. Setting phasers to stun... (port 3000) (ctrl-c to quit) }}} These warnings seem to be related to Windows-specific {{{.dll}}} files, including {{{kernel32.dll}}}, {{{user32.dll}}}, {{{msvcrt.dll}}}, {{{advapi32.dll}}}, and {{{ws2_32.dll}}}. As far as I can tell, there are no problems other than the warnings themselves, but I can't be sure. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9297> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #9878: Static pointers in GHCi cause panic
by GHC 22 Oct '15

22 Oct '15

#9878: Static pointers in GHCi cause panic -------------------------------------+------------------------------------- Reporter: monoidal | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.9 Keywords: | Operating System: Architecture: Unknown/Multiple | Unknown/Multiple Difficulty: Unknown | Type of failure: GHCi crash Blocked By: | Test Case: Related Tickets: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- I load this module into ghci {{{#!hs {-# LANGUAGE StaticPointers #-} module Static where import GHC.StaticPtr f = deRefStaticPtr (static True) }}} and get a panic upon evaluating `f` {{{ > f ghc: panic! (the 'impossible' happened) (GHC version 7.9.20141210 for x86_64-unknown-linux): Loading temp shared object failed: /tmp/ghc30486_0/ghc30486_5.so: undefined symbol: Static_sptEntryZC0_closure Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}} Am I doing static pointers right? -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9878> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #10149: The argument of mask does not always restore the masking state
by GHC 22 Oct '15

22 Oct '15

#10149: The argument of mask does not always restore the masking state -------------------------------------+------------------------------------- Reporter: | Owner: facundo.dominguez | Status: new Type: bug | Milestone: Priority: normal | Version: 7.8.4 Component: | Operating System: Unknown/Multiple libraries/base | Type of failure: None/Unknown Keywords: | Blocked By: Architecture: | Related Tickets: Unknown/Multiple | Test Case: | Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- In the documentation of `mask` and `uninterruptibleMask` it is claimed that the `restore` argument restores the masking state. However this is not true in the following programs: {{{#!hs mask_ $ -- start with exceptions masked mask $ \restore -> forkIOWithUnmask $ \unmask -> unmask $ restore $ getMaskingState >>= print }}} {{{#!hs uninterruptibleMask_ $ -- start with exceptions uninterruptibly masked uninterruptibleMask $ \restore -> forkIOWithUnmask $ \unmask -> unmask $ restore $ getMaskingState >>= print }}} The expected state is that `getMaskingState` would produce `MaskedInterruptible` and `MaskedUninterruptible`, however, in both cases it gives Unmasked. Either the documentation needs to be changed, or the implementation must really restore the masking state in these cases. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10149> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #10014: Data.Array.Base.elems needlessly calls bounds.
by GHC 21 Oct '15

21 Oct '15

#10014: Data.Array.Base.elems needlessly calls bounds. -------------------------------------+------------------------------------- Reporter: ekmett | Owner: ekmett Type: feature | Status: new request | Milestone: Priority: normal | Version: 7.8.4 Component: Core | Operating System: Unknown/Multiple Libraries | Type of failure: Runtime Keywords: | performance bug Architecture: | Blocked By: Unknown/Multiple | Related Tickets: Test Case: | Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- {{{ elems arr = case bounds arr of (_l, _u) -> [unsafeAt arr i | i <- [0 .. numElements arr - 1]] }}} It never uses the result. I'd propose simplifying it to {{{ elems arr = [unsafeAt arr i | i <- [0 .. numElements arr - 1]] }}} It appears at some point someone optimized it to use the `unsafeAt`, but never removed the bounds check. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10014> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #10049: Lower level memcpy primop
by GHC 21 Oct '15

21 Oct '15

#10049: Lower level memcpy primop -------------------------------------+------------------------------------- Reporter: chadaustin | Owner: Type: feature | Status: new request | Milestone: Priority: normal | Version: 7.8.4 Component: Compiler | Operating System: Unknown/Multiple Keywords: | Type of failure: None/Unknown Architecture: | Blocked By: Unknown/Multiple | Related Tickets: Test Case: | Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- I'm doing some really low-level buffer stuff, and it would be quite helpful if there were lower-level memcpy primitives. I'm thinking something like: {{{#!hs copyBytes# :: Addr# -> Addr# -> Int# -> State# s -> State# s copyBytes dst src size _ = ... }}} I would expect it to compile, on x86, into "rep movsb", which is frequently optimal on Ivy Bridge and Haswell. The other memcpy primitives use Array# or MutableArray#, and it's not clear how, if all you have is an Addr#, how to get the corresponding Array# or MutableArray#. (Can you just cast?) It may be appropriate to have corresponding 16-bit and 32-bit operations; "rep movsw" and "rep movsd", respectively. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10049> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #8957: ghci's :l -> internal error: evacuate: strange closure type 8306
by GHC 21 Oct '15

21 Oct '15

#8957: ghci's :l -> internal error: evacuate: strange closure type 8306 ----------------------------------+------------------------------- Reporter: guest | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: GHCi | Version: 7.6.3 Keywords: | Operating System: Windows Architecture: x86_64 (amd64) | Type of failure: GHCi crash Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | ----------------------------------+------------------------------- GHCi crashes when :loading a file. Unfortunately I can't reproduce the bug, so this one's gonna be lots of information that probably will help very little. This is the actual error message: {{{ *CommonStatistics Data.List> :l SimpleCellularALife [1 of 2] Compiling CommonStatistics ( CommonStatistics.hs, interpreted ) <interactive>: internal error: evacuate: strange closure type 8306 (GHC version 7.6.3 for i386_unknown_mingw32) Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug This application has requested the Runtime to terminate it in an unusual way. Please contact the application's support team for more information. }}} This one was the error I was working on, i.e. the (legit) error in the previous call: (Including this because it gives you a clue what I was working on, I was mostly fiddling around with parens in placeAgents' gnd function) {{{ *CommonStatistics Data.List> :l SimpleCellularALife [1 of 2] Compiling CommonStatistics ( CommonStatistics.hs, interpreted ) [2 of 2] Compiling SimpleCellularALife ( SimpleCellularALife.hs, interpreted ) SimpleCellularALife.hs:70:28: Couldn't match expected type `Array i0 e0' with actual type `Ground' In the return type of a call of `ground' In the first argument of `(!)', namely `ground (tiles w)' In the expression: (ground (tiles w) ! (fst $ head grp)) SimpleCellularALife.hs:70:36: Couldn't match expected type `Tile' with actual type `Array Coordinates Tile' In the return type of a call of `tiles' In the first argument of `ground', namely `(tiles w)' In the first argument of `(!)', namely `ground (tiles w)' Failed, modules loaded: CommonStatistics. }}} Included Source Files - CommonStatistics.hs: {{{ module CommonStatistics where type Memory = [Int]--Internal state of an Agent. data StatUpdate = StatUpdate{ newVictories :: [Int] -- by agentID } deriving (Show) data Agent = Agent{ agentID :: Int, sourcePath :: FilePath, --path to .hs source file. relative to executable doFunc :: [String] -> Memory -> (Memory, [String]), evFunc :: [String] -> Memory -> (Memory, String), personalMemory :: Memory } instance Show Agent where show (Agent { agentID = aID, sourcePath = path, doFunc = forgetit, evFunc = forgetittoo, personalMemory = mem }) = show (aID, path, mem) }}} And SimpleCellularALife.hs: (I am not exactly confident that this is the version that caused the error. I sadly can't reproduce it, so there's no confirming that. {{{ module SimpleCellularALife where import Data.Array import Data.List import System.Random import CommonStatistics data Ground = Ground { food :: Int } data Entity = Entity{ ai :: Agent, health :: Int } data Tile = Tile{ ground :: Ground, entities :: [Entity] } data World = World { tiles :: Array Coordinates Tile } type Coordinates = (Int, Int) getRandomPosition :: RandomGen t => World -> t -> (t, Coordinates) getRandomPosition w rand = let ((minx, miny), (maxx, maxy)) = bounds $ tiles w (x, rand2) = randomR (minx, maxx) rand (y, rand3) = randomR (miny, maxy) rand2 in (rand3, (x, y)) placeAgents :: RandomGen t => World -> [Agent] -> t -> (t, World) placeAgents w agents rand = let createTileUpdates (ag:ags) wrld rnd = let (rnd2, coords) = getRandomPosition wrld rnd (rnd3, restUpd) = createTileUpdates ags wrld rnd2 in (rnd3, (coords, ag) : restUpd) createTileUpdates [] wrld rnd = (rnd, []) (rand2, assocList) = createTileUpdates agents w rand groupedAssocList = groupBy (\(c1, a1) (c2, a2) -> c1 == c2) $ sortBy (\(c1, a1) (c2, a2) -> compare c1 c2) assocList gnd grp = ground ((tiles w) ! (fst $ head grp)) condenseGroup grp = (fst $ head grp, Tile{ground = gnd grp, entities = snd $ unzip grp}) --map condenseGroup groupedAssocList --::(Coordinates, Tile) in (rand, w) --placeAgents (placeAgent w firstAg x y) agents rand3 }}} Someone suggested that this might've been GHCI running out of memory. I am as of writing this at 66% out of 4GB used. The GHCI instance was opened for an extended period of time, so it might have racked up quite a bit of RAM usage. I can say though that considering the file sizes, 1.3GB of RAM usage seems unreasonable. And because I haven't yet written enough, here are all the variations of the line I was working on that could've caused it. Pulled them out of my text editor's buffer. {{{ gnd grp = (ground (tiles w) ! fst $ head grp) gnd grp = (ground (tiles w) ! (fst $ head grp) gnd grp = (ground (tiles w) ! (fst $ head grp)) gnd grp = (ground ((tiles w) ! (fst $ head grp)) gnd grp = ground ((tiles w) ! (fst $ head grp)) }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8957> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #8687: Strange closure type 9983
by GHC 21 Oct '15

21 Oct '15

#8687: Strange closure type 9983 ------------------------------------+------------------------------- Reporter: nh2 | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.6.3 Keywords: | Operating System: Windows Architecture: Unknown/Multiple | Type of failure: GHCi crash Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | ------------------------------------+------------------------------- {{{ *Main> :main C:\\Windows\\Media\\onestop.mid <interactive>: internal error: evacuate: strange closure type 9983 (GHC version 7.6.3 for i386_unknown_mingw32) Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug This application has requested the Runtime to terminate it in an unusual way. Please contact the application's support team for more information. }}} This happened to me on {{{ghci playmidi.hs}}} from the {{{examples/}}} folder of {{{http://hackage.haskell.org/package/hmidi-0.2.1.0}}} (downloaded the tar and fixed the parsec import, removing the {{{"parsec2"}}} package import and fixing a type checking error, replacing {{{selectOutputDevice Nothing}}} by {{{selectOutputDevice "Select midi output device" Nothing}}}. (We also fixed those compile errors at https://github.com/vahokif/hmidi/tree/2124a8.) I have not been able to reproduce it since the first time :( -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8687> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #8648: Initialization of C statics broken in threaded runtime
by GHC 20 Oct '15

20 Oct '15

#8648: Initialization of C statics broken in threaded runtime ------------------------------------+------------------------------------- Reporter: edsko | Owner: simonmar Type: bug | Status: new Priority: normal | Milestone: Component: Runtime System | 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: | ------------------------------------+------------------------------------- Consider a tiny package `static-value`, consisting of one Haskell file {{{ foreign import ccall unsafe "returnStaticValue" c_returnStaticValue :: IO CInt printStaticValue :: IO () printStaticValue = print =<< c_returnStaticValue }}} and one corresponding C file {{{ static int theStaticValue = 0; int returnStaticValue() { // Modify the static so the C compiler doesn't optimize it away return theStaticValue++; } }}} (test case is attached). If we call `printStaticValue` using the GHC API: {{{ runGhc (Just libdir) $ do flags0 <- getSessionDynFlags void $ setSessionDynFlags flags0 { hscTarget = HscInterpreted , ghcLink = LinkInMemory , ghcMode = CompManager } setContext $ [ IIDecl $ simpleImportDecl $ mkModuleName "StaticValue" ] _ <- runStmt "StaticValue.printStaticValue" RunToCompletion }}} then we see "0", as expected. However, if we compile this code using the threaded runtime, and we wrap the above code in a call to either `forkIO` or `forkOS`, then we see a different value printed (-907777, whatever that value is). Some notes: * I have been unable to reproduce this bug without using GHC as API; in particular, calling `printStaticValue` directly, wrapped in `forkIO` or `forkOS` or not, always works as expected. * If I change the initialization value of `staticValue` from 0 to anything else (say, 1234), we always get the right answer, never the uninitialized value. Presumably this is because non-zero values require some explicit code to be run (and it does get run), while a zero value gets initialized differently (and apparently, that's where the bug is). * I have reproduced this bug in both ghc 7.4 and 7.7.20131227. This ticket is the result of tracking down a problem with calling `createProcess` from within the GHC API, which would cause the parent process to stall. As it turns out, `runProcess.c` (from the `process` library) declares a `static long max_fd = 0`, and in `runInteractiveProcess` checks for this value to be 0, and if it is, does a syscall to figure out what the maximum FD is. But since this static does not get initialized properly (the bug reported in this ticket), it gets left at its (random? but always the same) value (281474975802879), so that the child process proceeds to close rather too many file descriptors (if close_fds was set to True) and the parent stalls. Indeed, changing the initialization to `static long max_fd = -1` (and adjusting the later check for zero accordingly) fixes this (so this is a viable workaround in `process` if we cannot track down the bug in GHC). -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8648> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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