Resolving dependencies... Downloading flatparse-0.3.0.1 Downloaded flatparse-0.3.0.1 Starting flatparse-0.3.0.1 Building flatparse-0.3.0.1 Failed to install flatparse-0.3.0.1 Build log ( /home/builder/.cabal/logs/ghc-8.10.2/flatparse-0.3.0.1-2Fbw54yGnz58r0UGfcFyQG.log ): cabal: Entering directory '/tmp/cabal-tmp-29452/flatparse-0.3.0.1' Configuring flatparse-0.3.0.1... Preprocessing library for flatparse-0.3.0.1.. Building library for flatparse-0.3.0.1.. : error: Warning: Couldn't figure out LLVM version! Make sure you have installed LLVM 9 : error: Warning: Couldn't figure out LLVM version! Make sure you have installed LLVM 9 : error: Warning: Couldn't figure out LLVM version! Make sure you have installed LLVM 9 : error: Warning: Couldn't figure out LLVM version! Make sure you have installed LLVM 9 : error: Warning: Couldn't figure out LLVM version! Make sure you have installed LLVM 9 : error: Warning: Couldn't figure out LLVM version! Make sure you have installed LLVM 9 [1 of 6] Compiling FlatParse.Internal ( src/FlatParse/Internal.hs, dist/build/FlatParse/Internal.o, dist/build/FlatParse/Internal.dyn_o ) : error: Warning: Couldn't figure out LLVM version! Make sure you have installed LLVM 9 ghc: could not execute: opt cabal: Leaving directory '/tmp/cabal-tmp-29452/flatparse-0.3.0.1' cabal: Error: some packages failed to install: flatparse-0.3.0.1-2Fbw54yGnz58r0UGfcFyQG failed during the building phase. The exception was: ExitFailure 1