Broken XMonad (Dependencies) after Pacman Update (How to compile it with Stack?)

Question

This question is the distilled solution of what others have helped me solved. The discussion can be found on this issue and this r/xmonad post.

I'm using Artix mainly with Pacman as a package manager. Today, after about a week, I've upgraded many packages and it ended up breaking XMonad.

This is the message I get from xmonad --recompile -v:

XMonad is recompiling and replacing itself another XMonad process because the current process is called "xmonad" but the compiled configuration should be called "xmonad-x86_64-linux"
XMonad will use ghc to recompile, because "/home/philippe/.xmonad/build" does not exist.
XMonad skipping recompile because it is not forced (e.g. via --recompile), and neither xmonad.hs nor any *.hs / *.lhs / *.hsc files in lib/ have been changed.
/home/philippe/.xmonad/xmonad-x86_64-linux: error while loading shared libraries: libHSxmonad-contrib-0.16-KKfUmtIonstICqbgIKQKYh-ghc8.10.4.so: cannot open shared object file: No such file or directory

I've tried a ton of solutions people mentioned on the internet — so far I've spent more than 3 hours trying to debug this —, among them, notably:

• cabal install --lib xmonad-contrib, which had solved some issues I've had with XMonad in the past.
• Removing and reinstalling Stack, GHC, Cabal, and XMonad itself.
• Installing XMonad through Stack.
  • This ended up giving me the same error message, the difference is that I had to execute ~/.local/bin/xmonad --recompile -v instead.

Does anyone have an idea of how to solve this? I've had problems with upgrades of XMonad before, but never anything close to this — I love Haskell as a language, but its package management is one of the most disgusting, overcomplicated pieces of software I've ever experienced in my 10+ years of programming life.

If I end up cleaning up my system and managing everything through Stack, how do I compile XMonad through it? Using only Stack and then xmonad --recompile is giving me this error:

XMonad will use ghc to recompile, because "/home/philippe/.xmonad/build" does not exist.
xmonad: ghc: runProcess: runInteractiveProcess: exec: inappropriate type (Not a directory)

(I do have an ~/.xmonad/build/ folder by the way...)

Answer 1

I've finally made it work. The guys from the XMonad repo really helped, you can check out their help in this issue.

Roughly, what I did was:

1. Delete everything Haskell-related from my system.
   • Do this one carefully, use a lot of finds with the words haskell, stack, ghc, cabal, etc. Don't forget to use pacman -Rns and pacman -Q to uninstall everything that come from there first.
   • As some other users mentioned, you should absolutely not manage Haskell packages with both Pacman/AUR and Stack/Cabal. Choose one system and stick to it. Stack is probably the recommended one.
2. Install Stack directly with the script on its documentation.
3. Install GHC, XMonad, and XMonad-Contrib through Stack.
4. Create a build script for compiling XMonad with Stack:

   #!/bin/sh
   
   exec stack ghc --  \
     --make xmonad.hs \
     -i               \
     -ilib            \
     -fforce-recomp   \
     -main-is main    \
     -v0              \
     -o "$1"jk
   

5. Add exec $HOME/.xmonad/xmonad-x86_64-linux to .xinitrc so it runs what was compiled with Stack previously.