Internal error during typechecking of a hole in GHCi when there's shadowed identifiers
GHCi, version 8.4.3: http://www.haskell.org/ghc/ :? for help Prelude> let x = () Prelude> let x = () Prelude> :t _ <interactive>:1:1: error: GHC internal error: ‘Ghci1.x’ is not in scope during type checking, but it passed the renamer tcl_env of environment: 
Seems to only happen when there were two identifiers defined with the same name.
As verified by mpickering on IRC this isn't reproducible in 8.2.2.