Question

When I try to install the “encoding” library, I get this failure, but I can’t find any documentation to tell me what it means:

$ sudo cabal install encoding --global
Resolving dependencies...
cabal: Error: some packages failed to install:
encoding-0.6.6 failed during the configure step. The exception was:
ExitFailure 127

EDIT: With verbose logging, I have:

$ cabal install encoding --global -v
Reading available packages...
Resolving dependencies...
In order, the following would be installed:
encoding-0.6.6 (new package)
Extracting
/home/aditya/.cabal/packages/hackage.haskell.org/encoding/0.6.6/encoding-0.6.6.tar.gz
to /tmp/encoding-0.6.610687...
creating /tmp/encoding-0.6.610687/encoding-0.6.6/dist/setup
/tmp/encoding-0.6.610687/encoding-0.6.6/dist/setup/setup configure --verbose=2
--ghc --global --flags=newghc --flags=splitbase --constraint=HaXml ==1.22.5
--constraint=array ==0.3.0.2 --constraint=base ==4.3.1.0 --constraint=binary
==0.5.1.0 --constraint=bytestring ==0.9.1.10 --constraint=containers ==0.4.0.0
--constraint=extensible-exceptions ==0.1.1.2 --constraint=ghc ==7.0.3
--constraint=ghc-prim ==0.2.0.0 --constraint=mtl ==2.0.1.0
--constraint=regex-compat ==0.93.1
World file is already up to date.
cabal: Error: some packages failed to install:
encoding-0.6.6 failed during the configure step. The exception was:
ExitFailure 127

This still doesn’t seem to tell me what C library dependency could be missing.

Answer 1

This typically means that C libraries were missing, that were required by the package (or one of its dependencies).

Turning on verbose logging should help.

$ cabal install encoding -v