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Unable to build with `GHC`

This works
```
cabal build
    
```
This fails
```
ghc --make Main.hs
    
```
This fixes ghc build
```
ghc --make -XHaskell2010 Main.hs
    
```
GHC2021 is used by GHC if neither Haskell98 nor Haskell2010 is turned on explicitly.
- GHC2021 enable StandaloneKindSignatures hence it supposes work.
- Haskell2010 has CUSKs, which is legacy extension that fixes user specified kind signature.
- GHC2021 is new feature since 9.2.1
- Follow up this problem here.
Reference
- GHC guide - control extensions
Tips
- cabal build --verbose to see what being passed to GHC