chroot cleanup

so, the build failed after 28 hours of compilation time (not 26 as I first thought). Since the time between two builds is the ideal moment to kill buildd if you don't want to interrupt what it's doing, I'm performing some chroot maintenance now: 
0 upgraded, 0 newly installed, 104 to remove and 77 not upgraded.
Need to get 0B of archives.
After unpacking 150MB disk space will be freed.
Do you want to continue? [Y/n]
Hm. That's needed :-)