Warning: The install command is a part of the legacy v1 style of cabal usage.

Please switch to using either the new project style and the new-install
command or the legacy v1-install alias as new-style projects will become the
default in the next version of cabal-install. Please file a bug if you cannot
replicate a working v1- use case with the new-style commands.

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Resolving dependencies...
Starting     load-font-0.1.0.3
Starting     primitive-0.7.0.0
Building     primitive-0.7.0.0
Building     load-font-0.1.0.3
Completed    load-font-0.1.0.3
Completed    primitive-0.7.0.0
Starting     vector-0.12.1.2
Building     vector-0.12.1.2
Completed    vector-0.12.1.2
Starting     fltkhs-0.8.0.3
Failed to install fltkhs-0.8.0.3
Build log ( /home/builder/.cabal/logs/ghc-8.6.3/fltkhs-0.8.0.3-8zBHx54ul1h8M5VX86Pay0.log ):
cabal: Entering directory '/tmp/cabal-tmp-11726/fltkhs-0.8.0.3'
cabal: Leaving directory '/tmp/cabal-tmp-11726/fltkhs-0.8.0.3'
cabal: Error: some packages failed to install:
fltkhs-0.8.0.3-8zBHx54ul1h8M5VX86Pay0 failed during the configure step. The
exception was:
dieVerbatim: user error (cabal: '/opt/ghc/bin/ghc' exited with an error:

/tmp/cabal-tmp-11726/fltkhs-0.8.0.3/dist/setup/setup.hs:397:39: error:
• Couldn't match expected type ‘Maybe
Distribution.Types.UnqualComponentName.UnqualComponentName
-> ComponentName’
with actual type ‘ComponentName’
• The function ‘CLibName’ is applied to one argument,
but its type ‘ComponentName’ has none
In the third argument of ‘componentNameTargets'’, namely
‘(CLibName (libName lib))’
In the expression:
componentNameTargets' pkg lbi (CLibName (libName lib))
|
397 | case componentNameTargets' pkg lbi (CLibName (libName lib)) of
| ^^^^^^^^^^^^^^^^^^^^^^
)
fltkhs-themes-0.2.0.3-4bB9KtVyHYLLbyTWR2DLMU depends on fltkhs-themes-0.2.0.3
which failed to install.