stack exec complains about missing GHC

[deepfire]

Issue description

stack exec complains about missing GHC.

Steps to reproduce

deepfire@andromedae:~$ nix-env --query --installed | grep 'ghc\|stack'
ghc-8.0.1
stack-1.3.0
deepfire@andromedae:~$ stack exec ghc
No compiler found, expected minor version match with ghc-8.0.1 (x86_64) (based on resolver setting in /home/deepfire/.stack/global-project/stack.yaml).
To install the correct GHC into /home/deepfire/.stack/programs/x86_64-linux/, try running "stack setup" or use the "--install-ghc" flag. To use your system GHC installation, run "stack config set system-ghc --global true", or use the "--system-ghc" flag.

Technical details

• System: 17.03.git.de99dc5 (Gorilla)
• Nix version: nix-env (Nix) 1.11.4
• Nixpkgs version: "17.03.git.de99dc5049"

[domenkozar]

stack --nix exec ghc

[deepfire]

@domenkozar, then we need to somehow accomodate this for intero to work properly

[deepfire]

@domenkozar, because https://github.com/commercialhaskell/intero/blob/master/elisp/intero.el#L1748