Cannot request GHC 8 on Trusty, even though it is already installed

Hi there,

My build at fails with “unknown ghc version”.

However, according to the documentation, the Trusty build image (which I have enabled) has ghc- pre-installed.

Removing the relevant lines from circle.yml does make it build again, but I’m not sure what version of GHC it uses now.

Does anyone know what’s going on here?


According to this build, the default version is indeed 8.0.1.

I’m guessing that the fact that GHC 8.0.1 is installed isn’t recorded in whatever applies the configuration.