As seen on the stackage build server:
Failures:
test/Data/YamlSpec.hs:67:
1) Data.Yaml.Data.Yaml encode/decode files with non-ASCII names
uncaught exception: ParseException (InvalidYaml (Just (YamlException "Yaml file not found: test/resources/accent\233/foo.yaml")))
I was able to reproduce locally like so:
$ stack unpack yaml-0.8.18.2
$ cd yaml-0.8.18.2/
$ stack init --resolver nightly-2016-08-31
$ stack test