I installed gtk+ 2.22 (without Glade). Now compilation succeeds :-)
The only thing I don't know is what I will do if I want to use glade (perhaps in a few weeks, perhaps never). Perhaps I can copy Gtk+ 2.22 over the bundled 2.20?
I tried to cabal install gtk-0.12.0 on Windows XP, with the bundeld GTK and Glade binary linked from http://www.haskell.org/haskellwiki/Gtk2Hs (glade3-3.6.7-with-GTK+.exe).
During compilation of gio-0.12.0, I got the error> [ 5 of 24] Compiling System.GIO.Volumes.VolumeMonitor (
> dist\build\System\GIO\Volumes\VolumeMonitor.o )
Then I looked at VolumeMonitor.hs and noticed something suspicious:
vmDriveStopButton is only #defined for GLIB 2.22, but it's exported without such a condition. I have GLIB 2.20. After fixing this, another similar error appears.
Any recommendation what I should do?