Adding `ghc-options` to a package from a `source-repository-package` not working

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This is the commit in question: cute-c2 ..doesnt compile due to duplicate record fields in re-export · ramirez7/theveryseriousjuniperdevgamejam2026@58c3539 · GitHub

I’m using the wasm backend toolchain (ghc 9.14.1.20260330 + cabal 3.14.2.0)

I thought I could specify ghc-options for my dependencies this way, but apparently not? It still fails to compile as if that extension isn’t enabled.

This isn’t a huge blocker (I can just commit a fix for the error) but I was surprised.

My library (cute-c2) is failing to compile because it re-exports some record fields that are duplicates but doesn’t declare {-# LANGUAGE DuplicateRecordFields #-} [1]

[1] The defining module does though..is this error new for re-exports?

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IIRC there shouldn’t be a colon in the first line, maybe that is the issue? That is, it should be package cute-c2 instead of package: cute-c2. It is weird that it is not a parse error if that is indeed the issue though.

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Oh I bet that is it! Agreed it’s weird I didn’t get an error..

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Just chiming in to say that you didn’t get an error because Cabal allows you to have “swung” indentation on fields, like this:

description: Hello,
  world!

You can use Gild (my tool) to format Cabal files, which would’ve made this a little more obvious:

$ curl --silent https://raw.githubusercontent.com/ramirez7/theveryseriousjuniperdevgamejam2026/58c35390ea3e4abe4f7e95a39bd21a5e430a43fc/cabal.project |
  cabal run cabal-gild |
  tail --lines 3
package:
  cute-c2
  ghc-options: -XDuplicateRecordFields
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Can gild be set up as an hls plugin?

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Looks like it’s on its way there: Format .cabal files with cabal-gild by fendor · Pull Request #4229 · haskell/haskell-language-server · GitHub

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I don’t use HLS, but I think Gild is already available as a plugin: Features — haskell-language-server 2.14.0.0 documentation

The PR @mixphix posted is for formatting HLS’s Cabal files with Gild.

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Whoops! On mobile right now, my apologies.