Resolving dependencies...
Starting     splitmix-0.1.0.3
Building     splitmix-0.1.0.3
Completed    splitmix-0.1.0.3
Starting     random-1.2.0
Building     random-1.2.0
Completed    random-1.2.0
Starting     factor-1.1
Building     factor-1.1
Failed to install factor-1.1
Build log ( /home/builder/.cabal/logs/ghc-8.10.2/factor-1.1-7KohjsxwtVm9cCdF2IoasU.log ):
cabal: Entering directory '/tmp/cabal-tmp-12012/factor-1.1'
Configuring factor-1.1...
Preprocessing library for factor-1.1..
Building library for factor-1.1..
[ 1 of 12] Compiling Factor.Gaussian  ( src/Factor/Gaussian.hs, dist/build/Factor/Gaussian.o, dist/build/Factor/Gaussian.dyn_o )
[ 2 of 12] Compiling Factor.Util      ( src/Factor/Util.hs, dist/build/Factor/Util.o, dist/build/Factor/Util.dyn_o )
[ 3 of 12] Compiling Factor.Prime     ( src/Factor/Prime.hs, dist/build/Factor/Prime.o, dist/build/Factor/Prime.dyn_o )
[ 4 of 12] Compiling Factor.Term      ( src/Factor/Term.hs, dist/build/Factor/Term.o, dist/build/Factor/Term.dyn_o )

src/Factor/Term.hs:517:28: error:
    Ambiguous occurrence ‘<>’
    It could refer to
       either ‘Prelude.<>’,
              imported from ‘Prelude’ at src/Factor/Term.hs:10:8-18
              (and originally defined in ‘GHC.Base’)
           or ‘Text.PrettyPrint.<>’,
              imported from ‘Text.PrettyPrint’ at src/Factor/Term.hs:18:26-29
              (and originally defined in ‘Text.PrettyPrint.HughesPJ’)
    |
517 | indexToDoc i = PP.char '_' <> PP.int i
    |                            ^^

src/Factor/Term.hs:524:46: error:
    Ambiguous occurrence ‘<>’
    It could refer to
       either ‘Prelude.<>’,
              imported from ‘Prelude’ at src/Factor/Term.hs:10:8-18
              (and originally defined in ‘GHC.Base’)
           or ‘Text.PrettyPrint.<>’,
              imported from ‘Text.PrettyPrint’ at src/Factor/Term.hs:18:26-29
              (and originally defined in ‘Text.PrettyPrint.HughesPJ’)
    |
524 | atomicToDoc (PrimeIndexTerm w) = PP.char 'P' <> indexToDoc w
    |                                              ^^

src/Factor/Term.hs:525:47: error:
    Ambiguous occurrence ‘<>’
    It could refer to
       either ‘Prelude.<>’,
              imported from ‘Prelude’ at src/Factor/Term.hs:10:8-18
              (and originally defined in ‘GHC.Base’)
           or ‘Text.PrettyPrint.<>’,
              imported from ‘Text.PrettyPrint’ at src/Factor/Term.hs:18:26-29
              (and originally defined in ‘Text.PrettyPrint.HughesPJ’)
    |
525 | atomicToDoc (NumberWidthTerm w) = PP.char 'N' <> widthToDoc w
    |                                               ^^

src/Factor/Term.hs:526:46: error:
    Ambiguous occurrence ‘<>’
    It could refer to
       either ‘Prelude.<>’,
              imported from ‘Prelude’ at src/Factor/Term.hs:10:8-18
              (and originally defined in ‘GHC.Base’)
           or ‘Text.PrettyPrint.<>’,
              imported from ‘Text.PrettyPrint’ at src/Factor/Term.hs:18:26-29
              (and originally defined in ‘Text.PrettyPrint.HughesPJ’)
    |
526 | atomicToDoc (PrimeWidthTerm w) = PP.char 'P' <> widthToDoc w
    |                                              ^^

src/Factor/Term.hs:527:50: error:
    Ambiguous occurrence ‘<>’
    It could refer to
       either ‘Prelude.<>’,
              imported from ‘Prelude’ at src/Factor/Term.hs:10:8-18
              (and originally defined in ‘GHC.Base’)
           or ‘Text.PrettyPrint.<>’,
              imported from ‘Text.PrettyPrint’ at src/Factor/Term.hs:18:26-29
              (and originally defined in ‘Text.PrettyPrint.HughesPJ’)
    |
527 | atomicToDoc (CompositeWidthTerm w) = PP.char 'C' <> widthToDoc w
    |                                                  ^^

src/Factor/Term.hs:534:42: error:
    Ambiguous occurrence ‘<>’
    It could refer to
       either ‘Prelude.<>’,
              imported from ‘Prelude’ at src/Factor/Term.hs:10:8-18
              (and originally defined in ‘GHC.Base’)
           or ‘Text.PrettyPrint.<>’,
              imported from ‘Text.PrettyPrint’ at src/Factor/Term.hs:18:26-29
              (and originally defined in ‘Text.PrettyPrint.HughesPJ’)
    |
534 |     strip (ExpTerm t u) = (atomicToDoc t <> PP.char '^') : strip u
    |                                          ^^

src/Factor/Term.hs:544:42: error:
    Ambiguous occurrence ‘<>’
    It could refer to
       either ‘Prelude.<>’,
              imported from ‘Prelude’ at src/Factor/Term.hs:10:8-18
              (and originally defined in ‘GHC.Base’)
           or ‘Text.PrettyPrint.<>’,
              imported from ‘Text.PrettyPrint’ at src/Factor/Term.hs:18:26-29
              (and originally defined in ‘Text.PrettyPrint.HughesPJ’)
    |
544 | negateToDoc (NegateTerm t) = PP.char '-' <> prodToDoc t
    |                                          ^^
cabal: Leaving directory '/tmp/cabal-tmp-12012/factor-1.1'
cabal: Error: some packages failed to install:
factor-1.1-7KohjsxwtVm9cCdF2IoasU failed during the building phase. The
exception was:
ExitFailure 1