GHC 9.10.2: internal error: ARR_WORDS object (0x4200b1cf68) entered!

[sgillespie]

Your environment

Which OS do you use?
NixOS

Which version of GHC do you use and how did you install it?
GHC 9.10.2 from haskell.nix

How is your project built (alternative: link to the project)?
This is HLS on HLS, built from the haskell.nix shell using cabal build

Which LSP client (editor/plugin) do you use?
Neovim+neovim/nvim-lspconfig

Which version of HLS do you use and how did you install it?
Latest master

Have you configured HLS in any way (especially: a hie.yaml file)?
No, only what is in the repository

Steps to reproduce

1. Build HLS with GHC 9.10.2
2. Open plugins/hls-refactor-plugin/src/Development/IDE/Plugin/Plugins/FillHole.hs
3. Make a change
4. Restart HLS (In nvim, :LspRestart

Expected behaviour

HLS does not crash

Actual behaviour

HLS crashes after reporting:

"haskell-language-server: internal error: ARR_WORDS object (0x4200b1cf68) entered!\n    (GHC version 9.10.2 for x86_64_unknown_linux)\n    Please report this as a GHC bug:  https://www.haskell.org/ghc/reportabug\n"

Debug information

Relevant startup log:

"2025-07-25T02:30:26.132827Z | Debug | Build profile: -w ghc-9.10.2 -O1\n"
"2025-07-25T02:30:26.133060Z | Debug | In order, the following will be built (use -v for more details):\n"
"2025-07-25T02:30:26.133163Z | Debug |  - haskell-language-server-2.11.0.0 (interactive) (lib:hls-refactor-plugin) (first run)\n"
"2025-07-25T02:30:26.253080Z | Debug | Preprocessing library 'hls-refactor-plugin' for haskell-language-server-2.11.0.0...\n"
"2025-07-25T02:30:26.339931Z | Debug | cabal path --output-format=json\n"
"2025-07-25T02:30:26.382759Z | Debug | /nix/store/dlmzrn4s0kxwkicsg2b2wxyzx2qxsfp7-ghc-shell-for-packages-ghc-9.10.2-env/bin/ghc --print-libdir\n"
"2025-07-25T02:30:26.421502Z | Debug | cabal path --output-format=json\n"
"2025-07-25T02:30:26.461501Z | Debug | /nix/store/dlmzrn4s0kxwkicsg2b2wxyzx2qxsfp7-ghc-shell-for-packages-ghc-9.10.2-env/bin/ghc --numeric-version\n"
'2025-07-25T02:30:26.461852Z | Debug | Session loading result: Right (ComponentOptions {componentOptions = ["-fbuilding-cabal-package","-O0","-outputdir","/home/sgillespie/.cache/hie-bios/dist-haskell-language-server-ccd5fdede35faf3d569dc3d8e551e25c/build/x86_64-linux/ghc-9.10.2/haskell-language-server-2.11.0.0/l/hls-refactor-plugin/build/hls-refactor-plugin","-odir","/home/sgillespie/.cache/hie-bios/dist-haskell-language-server-ccd5fdede35faf3d569dc3d8e551e25c/build/x86_64-linux/ghc-9.10.2/haskell-language-server-2.11.0.0/l/hls-refactor-plugin/build/hls-refactor-plugin","-hidir","/home/sgillespie/.cache/hie-bios/dist-haskell-language-server-ccd5fdede35faf3d569dc3d8e551e25c/build/x86_64-linux/ghc-9.10.2/haskell-language-server-2.11.0.0/l/hls-refactor-plugin/build/hls-refactor-plugin","-hiedir","/home/sgillespie/.cache/hie-bios/dist-haskell-language-server-ccd5fdede35faf3d569dc3d8e551e25c/build/x86_64-linux/ghc-9.10.2/haskell-language-server-2.11.0.0/l/hls-refactor-plugin/build/hls-refactor-plugin/extra-compilation-artifacts/hie","-stubdir","/home/sgillespie/.cache/hie-bios/dist-haskell-language-server-ccd5fdede35faf3d569dc3d8e551e25c/build/x86_64-linux/ghc-9.10.2/haskell-language-server-2.11.0.0/l/hls-refactor-plugin/build/hls-refactor-plugin","-i","-iplugins/hls-refactor-plugin/src","-i/home/sgillespie/.cache/hie-bios/dist-haskell-language-server-ccd5fdede35faf3d569dc3d8e551e25c/build/x86_64-linux/ghc-9.10.2/haskell-language-server-2.11.0.0/l/hls-refactor-plugin/build/hls-refactor-plugin","-i/home/sgillespie/.cache/hie-bios/dist-haskell-language-server-ccd5fdede35faf3d569dc3d8e551e25c/build/x86_64-linux/ghc-9.10.2/haskell-language-server-2.11.0.0/l/hls-refactor-plugin/build/hls-refactor-plugin/autogen","-i/home/sgillespie/.cache/hie-bios/dist-haskell-language-server-ccd5fdede35faf3d569dc3d8e551e25c/build/x86_64-linux/ghc-9.10.2/haskell-language-server-2.11.0.0/l/hls-refactor-plugin/build/global-autogen","-I/home/sgillespie/.cache/hie-bios/dist-haskell-language-server-ccd5fdede35faf3d569dc3d8e551e25c/build/x86_64-linux/ghc-9.10.2/haskell-language-server-2.11.0.0/l/hls-refactor-plugin/build/hls-refactor-plugin/autogen","-I/home/sgillespie/.cache/hie-bios/dist-haskell-language-server-ccd5fdede35faf3d569dc3d8e551e25c/build/x86_64-linux/ghc-9.10.2/haskell-language-server-2.11.0.0/l/hls-refactor-plugin/build/global-autogen","-I/home/sgillespie/.cache/hie-bios/dist-haskell-language-server-ccd5fdede35faf3d569dc3d8e551e25c/build/x86_64-linux/ghc-9.10.2/haskell-language-server-2.11.0.0/l/hls-refactor-plugin/build/hls-refactor-plugin","-optP-include","-optP/home/sgillespie/.cache/hie-bios/dist-haskell-language-server-ccd5fdede35faf3d569dc3d8e551e25c/build/x86_64-linux/ghc-9.10.2/haskell-language-server-2.11.0.0/l/hls-refactor-plugin/build/hls-refactor-plugin/autogen/cabal_macros.h","-this-unit-id","haskell-language-server-2.11.0.0-inplace-hls-refactor-plugin","-hide-all-packages","-Wmissing-home-modules","-no-user-package-db","-package-db","/home/sgillespie/.local/state/cabal/store/ghc-9.10.2-inplace/package.db","-package-db","/home/sgillespie/.cache/hie-bios/dist-haskell-language-server-ccd5fdede35faf3d569dc3d8e551e25c/packagedb/ghc-9.10.2","-package-db","/home/sgillespie/.cache/hie-bios/dist-haskell-language-server-ccd5fdede35faf3d569dc3d8e551e25c/build/x86_64-linux/ghc-9.10.2/haskell-language-server-2.11.0.0/l/hls-refactor-plugin/package.conf.inplace","-package-id","base-4.20.1.0-inplace","-package-id","bytestring-0.12.2.0-inplace","-package-id","containers-0.7-inplace","-package-id","deepseq-1.5.0.0-inplace","-package-id","dlist-1.0-BRkFyhrnf2gAqPbPv0DKDH","-package-id","extra-1.8-4UthXfafDiI53yWjggQ2Np","-package-id","ghc-9.10.2-inplace","-package-id","ghc-boot-9.10.2-inplace","-package-id","ghc-exactprint-1.10.0.0-B98f8GGIpVcIgpM3f8jL3B","-package-id","ghcide-2.11.0.0-inplace","-package-id","hls-graph-2.11.0.0-inplace","-package-id","hls-plugin-api-2.11.0.0-inplace","-package-id","lens-5.3.4-BRQ5B6odwd1KHg2I2i8Lka","-package-id","lsp-2.7.0.1-5Dk24pKjnRhHKOSlIc31iN","-package-id","mtl-2.3.1-inplace","-package-id","parser-combinators-1.3.0-AZPQifD2u9XAGjjtwsklEW","-package-id","regex-applicative-0.3.4-LpFYAP5LAB06rIBZEWjhyo","-package-id","regex-tdfa-1.3.2.4-I9cUetuLSCWCf7Kjon2wDb","-package-id","syb-0.7.2.4-8QhDaSTJ74qKpmP6apH5VS","-package-id","text-2.1.2-inplace","-package-id","text-rope-0.3-Fq1JVsU5Fos8TdLQZDN0vX","-package-id","time-1.12.2-inplace","-package-id","transformers-0.6.1.1-inplace","-package-id","unordered-containers-0.2.20-4FBlVESvUyCKzqDeEuCeFl","-XGHC2021","-XExplicitNamespaces","-XCPP","-XDataKinds","-XDerivingStrategies","-XDerivingVia","-XDuplicateRecordFields","-XFunctionalDependencies","-XLambdaCase","-XOverloadedStrings","-XPatternSynonyms","-XRecordWildCards","-XViewPatterns","Development.IDE.GHC.ExactPrint","Development.IDE.GHC.Compat.ExactPrint","Development.IDE.Plugin.CodeAction","Development.IDE.Plugin.CodeAction.Util","Development.IDE.GHC.Dump","Development.IDE.Plugin.CodeAction.Args","Development.IDE.Plugin.CodeAction.ExactPrint","Development.IDE.Plugin.CodeAction.PositionIndexed","Development.IDE.Plugin.Plugins.AddArgument","Development.IDE.Plugin.Plugins.Diagnostic","Development.IDE.Plugin.Plugins.FillHole","Development.IDE.Plugin.Plugins.FillTypeWildcard","Development.IDE.Plugin.Plugins.ImportUtils","-Wall","-Wredundant-constraints","-Wunused-packages","-Wno-name-shadowing","-Wno-unticked-promoted-constructors","-hide-all-packages","-haddock"], componentRoot = "/home/sgillespie/dev/haskell/haskell-language-server", componentDependencies = ["haskell-language-server.cabal","cabal.project","cabal.project.local"]},"/nix/store/dlmzrn4s0kxwkicsg2b2wxyzx2qxsfp7-ghc-shell-for-packages-ghc-9.10.2-env/lib/ghc-9.10.2/lib","9.10.2")\n'
"2025-07-25T02:30:26.487726Z | Info | Interface files cache directory: /home/sgillespie/.cache/ghcide/haskell-language-server-2.11.0.0-inplace-hls-refactor-plugin-4dbc86b93197ef38c1d11456a650378024d3c59e\n"
"2025-07-25T02:30:26.504013Z | Info | Making new HscEnv. In-place unit ids: [ haskell-language-server-2.11.0.0-inplace-hls-refactor-plugin ]\n"
'2025-07-25T02:30:26.549397Z | Debug | New component cache HscEnvEq: (([],Just HscEnvEq 7),fromList [("cabal.project",Just 2025-07-21 13:41:38.777631389 UTC),("cabal.project.local",Nothing),("haskell-language-server.cabal",Just 2025-07-11 02:51:25.861141305 UTC)])\n'
"2025-07-25T02:30:26.582610Z | Debug | Finished build session\nAsyncCancelled\nHasCallStack backtrace:\n  collectBacktraces, called at libraries/ghc-internal/src/GHC/Internal/Exception.hs:169:13 in ghc-internal:GHC.Internal.Exception\n  toExceptionWithBacktrace, called at libraries/ghc-internal/src/GHC/Internal/IO.hs:260:11 in ghc-internal:GHC.Internal.IO\n  throwIO, called at libraries/ghc-internal/src/GHC/Internal/Control/Exception/Base.hs:195:43 in ghc-internal:GHC.Internal.Control.Exception.Base\n\n\n"
"2025-07-25T02:30:26.589497Z | Debug | Known files updated:\n"
'  fromList [(TargetModule (ModuleName "Development.IDE.Plugin.CodeAction.PositionIndexed"),fromList ["/home/sgillespie/dev/haskell/haskell-language-server/plugins/hls-refactor-plugin/src/Development/IDE/Plugin/CodeAction/PositionIndexed.hs"]),(TargetModule (ModuleName "Development.IDE.GHC.ExactPrint"),fromList ["/home/sgillespie/dev/haskell/haskell-language-server/plugins/hls-refactor-plugin/src/Development/IDE/GHC/ExactPrint.hs"]),(TargetModule (ModuleName "Development.IDE.GHC.Compat.ExactPrint"),fromList ["/home/sgillespie/dev/haskell/haskell-language-server/plugins/hls-refactor-plugin/src/Development/IDE/GHC/Compat/ExactPrint.hs"]),(TargetModule (ModuleName "Development.IDE.GHC.Dump"),fromList ["/home/sgillespie/dev/haskell/haskell-language-server/plugins/hls-refactor-plugin/src/Development/IDE/GHC/Dump.hs"]),(TargetModule (ModuleName "Development.IDE.Plugin.Plugins.FillHole"),fromList ["/home/sgillespie/dev/haskell/haskell-language-server/plugins/hls-refactor-plugin/src/Development/IDE/Plugin/Plugins/FillHole.hs"]),(TargetModule (ModuleName "Development.IDE.Plugin.CodeAction"),fromList ["/home/sgillespie/dev/haskell/haskell-language-server/plugins/hls-refactor-plugin/src/Development/IDE/Plugin/CodeAction.hs"]),(TargetFile NormalizedFilePath "/home/sgillespie/dev/haskell/haskell-language-server/plugins/hls-refactor-plugin/src/Development/IDE/Plugin/Plugins/FillHole.hs",fromList ["/home/sgillespie/dev/haskell/haskell-language-server/plugins/hls-refactor-plugin/src/Development/IDE/Plugin/Plugins/FillHole.hs"]),(TargetModule (ModuleName "Development.IDE.Plugin.Plugins.Diagnostic"),fromList ["/home/sgillespie/dev/haskell/haskell-language-server/plugins/hls-refactor-plugin/src/Development/IDE/Plugin/Plugins/Diagnostic.hs"]),(TargetModule (ModuleName "Development.IDE.Plugin.Plugins.ImportUtils"),fromList ["/home/sgillespie/dev/haskell/haskell-language-server/plugins/hls-refactor-plugin/src/Development/IDE/Plugin/Plugins/ImportUtils.hs"]),(TargetModule (ModuleName "Development.IDE.Plugin.Plugins.AddArgument"),fromList ["/home/sgillespie/dev/haskell/haskell-language-server/plugins/hls-refactor-plugin/src/Development/IDE/Plugin/Plugins/AddArgument.hs"]),(TargetModule (ModuleName "Development.IDE.Plugin.Plugins.FillTypeWildcard"),fromList ["/home/sgillespie/dev/haskell/haskell-language-server/plugins/hls-refactor-plugin/src/Development/IDE/Plugin/Plugins/FillTypeWildcard.hs"]),(TargetModule (ModuleName "Development.IDE.Plugin.CodeAction.Util"),fromList ["/home/sgillespie/dev/haskell/haskell-language-server/plugins/hls-refactor-plugin/src/Development/IDE/Plugin/CodeAction/Util.hs"]),(TargetModule (ModuleName "Development.IDE.Plugin.CodeAction.Args"),fromList ["/home/sgillespie/dev/haskell/haskell-language-server/plugins/hls-refactor-plugin/src/Development/IDE/Plugin/CodeAction/Args.hs"]),(TargetModule (ModuleName "Development.IDE.Plugin.CodeAction.ExactPrint"),fromList ["/home/sgillespie/dev/haskell/haskell-language-server/plugins/hls-refactor-plugin/src/Development/IDE/Plugin/CodeAction/ExactPrint.hs"])]\n'
"2025-07-25T02:30:26.589994Z | Debug | Restarting build session due to new component\nAction Queue: []\nKeys: [ IsFileOfInterest; /home/sgillespie/dev/haskell/haskell-language-server/plugins/hls-refactor-plugin/src/Development/IDE/Plugin/Plugins/FillHole.hs\n      , GhcSessionIO; \n      , GetKnownTargets;  ]\nAborting previous build session took 0.00s \n"
'2025-07-25T02:30:26.590779Z | Debug | hlint: Getting hlint ideas for  NormalizedFilePath "/home/sgillespie/dev/haskell/haskell-language-server/plugins/hls-refactor-plugin/src/Development/IDE/Plugin/Plugins/FillHole.hs"\n'
'2025-07-25T02:30:26.661533Z | Debug | hlint: Using extensions for  NormalizedFilePath "/home/sgillespie/dev/haskell/haskell-language-server/plugins/hls-refactor-plugin/src/Development/IDE/Plugin/Plugins/FillHole.hs":\n    [ MonomorphismRestriction\n    , RelaxedPolyRec\n    , ForeignFunctionInterface\n    , ImplicitPrelude\n    , ScopedTypeVariables\n    , BangPatterns\n    , OverloadedStrings\n'
"    , DisambiguateRecordFields\n    , RecordWildCards\n    , NamedFieldPuns\n    , ViewPatterns\n    , GADTSyntax\n    , DoAndIfThenElse\n    , ConstraintKinds\n    , PolyKinds\n    , DataKinds\n    , InstanceSigs\n    , StandaloneDeriving\n    , DeriveDataTypeable\n    , DeriveFunctor\n    , DeriveTraversable\n    , DeriveFoldable\n    , DeriveGeneric\n    , DeriveLift\n    , DerivingStrategies\n    , DerivingVia\n    , TypeSynonymInstances\n    , FlexibleContexts\n    , FlexibleInstances\n    , ConstrainedClassMethods\n    , MultiParamTypeClasses\n    , FunctionalDependencies\n    , ExistentialQuantification\n    , EmptyDataDecls\n    , KindSignatures\n"
"    , GeneralizedNewtypeDeriving\n    , PostfixOperators\n    , TupleSections\n    , PatternGuards\n    , RankNTypes\n    , TypeOperators\n    , ExplicitNamespaces\n    , ExplicitForAll\n    , TraditionalRecordSyntax\n    , LambdaCase\n    , BinaryLiterals\n    , HexFloatLiterals\n    , DuplicateRecordFields\n    , EmptyCase\n    , PatternSynonyms\n"
"    , NamedWildCards\n    , TypeApplications\n    , EmptyDataDeriving\n    , NumericUnderscores\n    , StarIsType\n    , ImportQualifiedPost\n    , StandaloneKindSignatures\n    , FieldSelectors\n    , ListTuplePuns ]\n"
"haskell-language-server: internal error: ARR_WORDS object (0x4200b1d080) entered!\n    (GHC version 9.10.2 for x86_64_unknown_linux)\n    Please report this as a GHC bug:  https://www.haskell.org/ghc/reportabug\n"

EDIT: I can reproduce with ghc9102 from nixpkgs, which would seem to rule out a problem from haskell.nix:

"haskell-language-server: internal error: ARR_WORDS object (0x42010071e8) entered!\nStack trace:\n"
"haskell-language-server: Failed to get stack frames of current process: No DWARF information found: Success\n            0x7fde16584570    set_initial_registers (/nix/store/ki6b1isnf9fy9qldhcv5ad0gyh5rch44-ghc-9.10.2/lib/ghc-9.10.2/lib/x86_64-linux-ghc-9.10.2/libHSrts-1.0.2_thr-ghc9.10.2.so)\n"
"            0x7fde15fbe660    dwfl_thread_getframes (/nix/store/qwmm6h7n1qk2xad64i4ncr9is17gfcf4-elfutils-0.193/lib/libdw-0.193.so)\n"
"            0x7fde15fbe07b    get_one_thread_cb (/nix/store/qwmm6h7n1qk2xad64i4ncr9is17gfcf4-elfutils-0.193/lib/libdw-0.193.so)\n            0x7fde15fbe464    dwfl_getthreads (/nix/store/qwmm6h7n1qk2xad64i4ncr9is17gfcf4-elfutils-0.193/lib/libdw-0.193.so)\n"
"            0x7fde15fbe9d2    dwfl_getthread_frames (/nix/store/qwmm6h7n1qk2xad64i4ncr9is17gfcf4-elfutils-0.193/lib/libdw-0.193.so)\n"
"            0x7fde16584cb7    libdwGetBacktrace (/nix/store/ki6b1isnf9fy9qldhcv5ad0gyh5rch44-ghc-9.10.2/lib/ghc-9.10.2/lib/x86_64-linux-ghc-9.10.2/libHSrts-1.0.2_thr-ghc9.10.2.so)\n"
"            0x7fde1658e137    rtsFatalInternalErrorFn (/nix/store/ki6b1isnf9fy9qldhcv5ad0gyh5rch44-ghc-9.10.2/lib/ghc-9.10.2/lib/x86_64-linux-ghc-9.10.2/libHSrts-1.0.2_thr-ghc9.10.2.so)\n"
"            0x7fde1658e38f    barf (/nix/store/ki6b1isnf9fy9qldhcv5ad0gyh5rch44-ghc-9.10.2/lib/ghc-9.10.2/lib/x86_64-linux-ghc-9.10.2/libHSrts-1.0.2_thr-ghc9.10.2.so)\n"
"            0x7fde165ce513    stg_ARR_WORDS_info (/nix/store/ki6b1isnf9fy9qldhcv5ad0gyh5rch44-ghc-9.10.2/lib/ghc-9.10.2/lib/x86_64-linux-ghc-9.10.2/libHSrts-1.0.2_thr-ghc9.10.2.so)\n"
"(GHC version 9.10.2 for x86_64_unknown_linux)\n    Please report this as a GHC bug:  https://www.haskell.org/ghc/reportabug\n"

Furthermore, I cannot reproduce this with ghc-9.10.1 (from either nixpkgs or haskell.nix)

[fendor]

cc @wz1000

[soulomoon]

same for hls-ormolu-plugin-tests

Running 1 test suites...
Test suite hls-ormolu-plugin-tests: RUNNING...
ormolu
  lib
    formats correctly:           OK (0.15s)
    formats imports correctly:   OK (0.12s)
hls-ormolu-plugin-tests: internal error: ARR_WORDS object (0x4201cb3ed0) entered!
    (GHC version 9.10.2 for x86_64_unknown_linux)
    Please report this as a GHC bug:  https://www.haskell.org/ghc/reportabug
    formats operators correctly: Test suite hls-ormolu-plugin-tests: FAIL
Test suite logged to:
/home/runner/work/haskell-language-server/haskell-language-server/./dist-newstyle/build/x86_64-linux/ghc-9.10.2/hls-2.11.0.0/t/hls-ormolu-plugin-tests/test/hls-2.11.0.0-hls-ormolu-plugin-tests.log
0 of 1 test suites (0 of 1 test cases) passed.

[sgillespie]

I just tested this on the newly released HLS 2.12.0.0, using exactly the steps above. Unfortunately, it is a problem there:

Info | cabal --builddir=/home/sgillespie/.cache/hie-bios/dist-haskell-language-server-ccd5fdede35faf3d569dc3d8e551e25c v2-repl --with-compiler /home/sgillespie/.cache/hie-bios/wrapper-b54f81dea4c0e6d1626911c526bc4e36 --with-hc-pkg /home/sgillespie/.cache/hie-bios/ghc-pkg-9caa5be081f5ef06def820b271326d60 /home/sgillespie/dev/haskell/haskell-language-server/plugins/hls-refactor-plugin/src/Development/IDE/Plugin/Plugins/FillHole.hs\n  Environment Variables\n    HIE_BIOS_OUTPUT: /tmp/HIE_BIOS_OUTPUT687799-0\n    HIE_BIOS_GHC: /nix/store/z5zjiwwgaa336zdy8vsiq7sdal7dlyc1-ghc-shell-for-packages-ghc-9.10.2-env/bin/ghc\n    HIE_BIOS_GHC_ARGS: -B/nix/store/z5zjiwwgaa336zdy8vsiq7sdal7dlyc1-ghc-shell-for-packages-ghc-9.10.2-env/lib/ghc-9.10.2/lib\n"
Info | Interface files cache directory: /home/sgillespie/.cache/ghcide/haskell-language-server-2.12.0.0-inplace-hls-refactor-plugin-b1cdc4e9c34738da1a3eb687c8a5ad8dd720803f\n"
Info | Making new HscEnv. In-place unit ids: [ haskell-language-server-2.12.0.0-inplace-hls-refactor-plugin ]\n"
# <-- A bunch of output
"haskell-language-server: internal error: ARR_WORDS object (0x4200807e70) entered!\n    (GHC version 9.10.2 for x86_64_unknown_linux)\n    Please report this as a GHC bug:  https://www.haskell.org/ghc/reportabug\n"

CC @wz1000

[AndreasPK]

Does this reproduce with ghc-9.10.3?

[sgillespie]

Does this reproduce with ghc-9.10.3?

It does:

haskell-language-server: internal error: ARR_WORDS object (0x4200807e08) entered!
haskell-language-server: Failed to get stack frames of current process: No DWARF information found: Success
            0x7f7d5db83970    set_initial_registers (/nix/store/4mr9hd1i6hc7xxjgddxlwvkf72mab5r8-ghc-9.10.3/lib/ghc-9.10.3/lib/x86_64-linux-ghc-9.10.3/libHSrts-1.0.2_thr-ghc9.10.3.so)
            0x7f7d5d5be660    dwfl_thread_getframes (/nix/store/hnzqas16kwcvaj2j5wb4izxdh692f9vn-elfutils-0.193/lib/libdw-0.193.so)
            0x7f7d5d5be07b    get_one_thread_cb (/nix/store/hnzqas16kwcvaj2j5wb4izxdh692f9vn-elfutils-0.193/lib/libdw-0.193.so)
            0x7f7d5d5be464    dwfl_getthreads (/nix/store/hnzqas16kwcvaj2j5wb4izxdh692f9vn-elfutils-0.193/lib/libdw-0.193.so)
            0x7f7d5d5be9d2    dwfl_getthread_frames (/nix/store/hnzqas16kwcvaj2j5wb4izxdh692f9vn-elfutils-0.193/lib/libdw-0.193.so)
            0x7f7d5db840b7    libdwGetBacktrace (/nix/store/4mr9hd1i6hc7xxjgddxlwvkf72mab5r8-ghc-9.10.3/lib/ghc-9.10.3/lib/x86_64-linux-ghc-9.10.3/libHSrts-1.0.2_thr-ghc9.10.3.so)
            0x7f7d5db8d437    rtsFatalInternalErrorFn (/nix/store/4mr9hd1i6hc7xxjgddxlwvkf72mab5r8-ghc-9.10.3/lib/ghc-9.10.3/lib/x86_64-linux-ghc-9.10.3/libHSrts-1.0.2_thr-ghc9.10.3.so)
            0x7f7d5db8d68f    barf (/nix/store/4mr9hd1i6hc7xxjgddxlwvkf72mab5r8-ghc-9.10.3/lib/ghc-9.10.3/lib/x86_64-linux-ghc-9.10.3/libHSrts-1.0.2_thr-ghc9.10.3.so)
            0x7f7d5dbcdd9b    stg_ARR_WORDS_info (/nix/store/4mr9hd1i6hc7xxjgddxlwvkf72mab5r8-ghc-9.10.3/lib/ghc-9.10.3/lib/x86_64-linux-ghc-9.10.3/libHSrts-1.0.2_thr-ghc9.10.3.so)

    (GHC version 9.10.3 for x86_64_unknown_linux)
    Please report this as a GHC bug:  https://www.haskell.org/ghc/reportabug

[sgillespie]

FWIW I cannot reproduce this on 9.12.2

[AndreasPK]

If someone could turn this into a non-interactive reproducer and open a ghc ticket it would be much appreciated.

[hasufell]

@maralorn is ghc9102 in nixpkgs patched? Is there any out-of-the-ordinary build configuration?

I tried this via ghcup, as in:

ghcup compile hls -g 2.12.0.0 --ghc 9.10.3

And I cannot reproduce this.

[maralorn]

All patches that we apply can be found here: https://github.com/NixOS/nixpkgs/blob/master/pkgs/development/compilers/ghc/common-hadrian.nix#L179 I can’t tell for sure but nothing seems to apply. So possibly this error would be reproducible with a compiler from nixpkgs.

(Just to be clear: This report uses a non-nixpkgs compiler out of haskell.nix.)