haskell-mode/ghc-mod "cannot open load file, no such file or directory, ghc"

[Gard Spreemann <gspr@nonempty.org>]

Hi,

As of late, I've been getting the below error message when loading a Haskell 
source file in Emacs on Stretch.


Loading /etc/emacs/site-start.d/50haskell-mode.el (source)...done
Loading /etc/emacs/site-start.d/51debian-el.el (source)...done
Loading /etc/emacs/site-start.d/51ghc-mod-el.el (source)...done
Loading paren...done
For information about GNU Emacs and the GNU system, type C-h C-a.
(New file)
File mode specification error: (file-error "Cannot open load file" "no such file 
or directory" "ghc")


Obviously, ghc-mod, haskell-mode and ghc are all installed, and GHC is
working fine.

I haven't been writing Haskell for about a month, so I don't know the
circumstances of when this started occurring. Does anybody have a
clue?


Best,
Gard