Configuring IfElse-0.85...
Building IfElse-0.85...
Preprocessing library IfElse-0.85...
[1 of 1] Compiling Control.Monad.IfElse ( Control/Monad/IfElse.hs, .stack-work/dist/x86_64-linux/Cabal-1.22.5.0/build/Control/Monad/IfElse.o )

Control/Monad/IfElse.hs:159:11: Warning:
    Rule "maybeMP/id" may never fire
      because ‘maybeMP’ might inline first
    Probable fix: add an INLINE[n] or NOINLINE[n] pragma on ‘maybeMP’
In-place registering IfElse-0.85...
Installing library in
/home/joey/.stack/snapshots/x86_64-linux/lts-5.5/7.10.3/lib/x86_64-linux-ghc-7.10.3/IfElse-0.85-EkfAH5IXGLU4RHYa9FeF8K
Registering IfElse-0.85...