-package Cabal-1.8.0.6 breaks pango installation on Mac

When installing Haskell pango on mac (sudo cabal install pango), the first problem is that it tries to install packages I've already installed. I've install haskell98 (successfully), but pango tries to install it again, and when the compilation is complete it gives this error:

Registering haskell98-1.0.1.1...
Installing library in /Users/username/.cabal/lib/haskell98-1.0.1.1/ghc-6.12.3
Registering haskell98-1.0.1.1...
<command line>: cannot satisfy -package Cabal-1.8.0.6: 
    Cabal-1.8.0.6-ec9be469687b5a514f4b7e8e2b8343c7 is unusable due to missing or recursive dependencies:
      process-1.0.1.3-1209536e5ce8f43dc64e390034356d63
    (use -v for more information)
<command line>: cannot satisfy -package Cabal-1.8.0.6: 
    Cabal-1.8.0.6-ec9be469687b5a514f4b7e8e2b8343c7 is unusable due to missing or recursive dependencies:
      process-1.0.1.3-1209536e5ce8f43dc64e390034356d63
    (use -v for more information)

So I used sudo cabal install pango -v, and this is the command that breaks开发者_C百科 the reinstallation of haskell98:

/usr/bin/ghc --make /tmp/glib-0.11.249666/glib-0.11.2/Setup.hs -o /tmp/glib-0.11.249666/glib-0.11.2/dist/setup/setup -odir /tmp/glib-0.11.249666/glib-0.11.2/dist/setup -hidir /tmp/glib-0.11.249666/glib-0.11.2/dist/setup -i -i/tmp/glib-0.11.249666/glib-0.11.2 -package Cabal-1.8.0.6

specifically the -package Cabal-1.8.0.6 part. What is wrong with this installation?

---

This isn't really an answer, but I can't format it well as a comment so I'm sticking it here.

First, are you installing into the user or global package directory (the default is the user directory unless you edited your .cabal file)? If you're putting it into the user dir, don't use sudo with cabal.

Secondly, have you run cabal install pango -v? The "-v" option displays what cabal thinks it needs to install, as well as more error messages, so it can be helpful.

Finally, run ghc-pkg describe Cabal to see which versions of Cabal are installed and their dependencies. It seems like somehow your Cabal-1.8.0.6 installation is unusable, but unfortunately I can't say why. If nothing depends on Cabal-1.8.0.6, I would suggest just unregistering it.