I'm trying to get HLS (Haskell Language Server) working in VSCode using WSL2 so I can get type hints. I've already ran through the week01 instructions so I have a working nix installation. However, when I run code within nix-shell to start the VSCode workspace, EnglishAuction.hs code fails in compilation. I tried removing the module section, suggested in this answer but the same error appears.

Here's the error message:

loadObj "/nix/store/jmhwwzn1yfjzlxavz16afkf1r4shmp8z-persistent-sqlite-lib-persistent-sqlite-": failedcompiler

Edit: Here's the entire output when I run haskell-language-server in the week01 directory:

haskell-language-server version: (GHC: (PATH: /nix/store/1f5m9aq39by56hbky1pz7dd52f4ikam8-haskell-language-server-exe-haskell-language-server-
 ghcide setup tester in /home/pioneer/plutus/plutus-pioneer-program/code/week01.
Report bugs at https://github.com/haskell/haskell-language-server/issues

Step 1/4: Finding files to test in /home/pioneer/plutus/plutus-pioneer-program/code/week01
Found 1 files

Step 2/4: Looking for hie.yaml files that control setup
Found 1 cradle

Step 3/4: Initializing the IDE

Step 4/4: Type checking the files
2022-01-17 22:25:09.635127929 [ThreadId 68] INFO hls:   Consulting the cradle for "src/Week01/EnglishAuction.hs"
Output from setting up the cradle Cradle {cradleRootDir = "/home/pioneer/plutus/plutus-pioneer-program/code/week01", cradleOptsProg = CradleAction: Cabal}
> Build profile: -w ghc- -O1
> In order, the following will be built (use -v for more details):
>  - plutus-pioneer-program-week01- (lib) (first run)
> Preprocessing library for plutus-pioneer-program-week01-
2022-01-17 22:25:10.848135893 [ThreadId 68] INFO hls:   Using interface files cache dir: /home/pioneer/.cache/ghcide/plutus-pioneer-program-week01-
2022-01-17 22:25:10.848331503 [ThreadId 68] INFO hls:   Making new HscEnv[plutus-pioneer-program-week01-]
GHC runtime linker: fatal error: I found a duplicate definition for symbol
whilst processing object file
The symbol was previously defined in
This could be caused by:
   * Loading two different object files which export the same symbol
   * Specifying the same object file twice on the GHCi command line
   * An incorrect `package.conf' entry, causing some object to be
     loaded twice.
2022-01-17 22:25:13.842245999 [ThreadId 205] INFO hls:  File:     /home/pioneer/plutus/plutus-pioneer-program/code/week01/src/Week01/EnglishAuction.hs
Hidden:   no
Range:    1:1-2:1
Source:   compiler
Severity: DsError
2022-01-17 22:25:13.842471029 [ThreadId 222] INFO hls:  finish: User TypeCheck (took 2.97s)
2022-01-17 22:25:13.842626898 [ThreadId 226] INFO hls:  finish: GetHie (took 0.00s)
Files that failed:
 * /home/pioneer/plutus/plutus-pioneer-program/code/week01/src/Week01/EnglishAuction.hs

Completed (0 files worked, 1 file failed)
2022-01-17 22:25:13.842743468 [ThreadId 228] INFO hls:  finish: GenerateCore (took 0.00s)

Edit2: The workaround from this answer allowed me to view more documentation, but still waiting for a complete solution.

1 Answer 1


there is a workaround how to replace that error by GHC Core to PLC plugin; E043:Error Haskell Language Server - linker error: symbol sqlite3_fts3_may_be_corrupt

other error should be solvable using this: https://github.com/input-output-hk/plutus-apps/blob/main/doc/plutus/troubleshooting.rst

but it didn't work for me

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    Jan 22, 2022 at 10:44
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