haskell/haskell-language-server

Windows/VS Code/Stack/HLS 2.12.0.0, regression from HLS 2.11.0.0?

Opened this issue · 1 comments

On Windows 11/VS Code/Stack, I am experiencing regression with a small 'toy' single-package project if I switch GHC 9.10.2 (LTS 24.11)/HLS 2.11.0.0 with GHC 9.10.3 (LTS 24.18)/HLS 2.12.0.0 (both HLS are GHCup-supplied).

Evaluate... does not trigger an evaluation.

The last lines of the 'OUTPUT' pane are:

Hidden:   no
Range:    1:1-2:1
Source:   compiler
Severity: DiagnosticSeverity_Error
Code:     <none>
Message: 
  �[0;91m(NeedsCompilation,NormalizedFilePath
  "D:\\Users\\mike\\Code\\Haskell\\lambertW\\.stack-work\\dist\\1a191874\\build\\lambertW-exe\\autogen\\Paths_lambertW.hs")user
  error (Failed to get the immediate reverse dependencies of NormalizedFilePath
  "D:\\Users\\mike\\Code\\Haskell\\lambertW\\.stack-work\\dist\\1a191874\\build\\lambertW-exe\\autogen\\Paths_lambertW.hs")�[0m
2025-11-02T18:24:51.669918Z | Info | Live bytes: 26.04MB Heap size: 599.79MB
haskell-language-server-9.10.3~2.12.0.0.exe: internal error: ARR_WORDS object (00007ff404efb060) entered!
    (GHC version 9.10.3 for x86_64_unknown_mingw32)
    Please report this as a GHC bug:  https://www.haskell.org/ghc/reportabug
haskell-language-server-wrapper-2.12.0.0.exe: callProcess: C:\ghcup\bin\haskell-language-server-9.10.3.exe "--lsp" (exit -1073740791): failed
[Error - 6:25:07 PM] The Haskell (lambertW) server crashed 5 times in the last 3 minutes. The server will not be restarted. See the output for more information.
[Error - 6:25:07 PM] Server process exited with code 1.

EDIT: A GitHub repository with my 'toy' project is here:

I am trying to add:

-- >>> lambertW0 1.0

to the Haddock comment for lambertW0. That works with GHC 9.10.2/HLS 2.11.0.0 but fails with GHC 9.10.3/HLS 2.12.0.0.

(The library builds fine with GHC 9.10.2 and GHC 9.10.3 and lambertW0 1.0 evaluates fine in stack ghci.)

fendor commented

Thank you for the bug report, this looks like the issue: #4674

Currently, we think this is caused by the hlint plugin somehow. Disabling it (in the editor config) seems to be a workaround for now.