fails to compile on 8.4.2 and probably (8.4.1)

[GeorgeCo]

fails to compile on 8.4.2 and probably (8.4.1)

cabal install -j5 llvm-general ... Failed to install llvm-general-pure-3.5.0.0 Build log ( /Users/gcolpitts/.cabal/logs/ghc-8.4.2/llvm-general-pure-3.5.0.0-K5dZ1oCl0eTJBIlvbqyDx8.log ): cabal: Entering directory '/var/folders/9b/rh4y2gy92hgdb6ktv4df1jv00000gn/T/cabal-tmp-72872/llvm-general-pure-3.5.0.0' Configuring llvm-general-pure-3.5.0.0... Warning: The package has an extraneous version range for a dependency on an internal library: llvm-general-pure ==3.5.0.0. This version range includes the current package but isn't needed as the current package's library will always be used. ... Preprocessing library for llvm-general-pure-3.5.0.0.. Building library for llvm-general-pure-3.5.0.0.. ... [27 of 28] Compiling LLVM.General.Internal.PrettyPrint ( src/LLVM/General/Internal/PrettyPrint.hs, dist/build/LLVM/General/Internal/PrettyPrint.o )

src/LLVM/General/Internal/PrettyPrint.hs:61:10: error: • No instance for (Semigroup QTree) arising from the superclasses of an instance declaration • In the instance declaration for ‘Monoid QTree’ | 61 | instance Monoid QTree where ...

[andrewerf]

I've faced this issue today. Has it not been fixed since then? Did you find workaround?