Saved package config file seems to be corrupt

[freeman42x]

Following steps:

cabal clean
rm *.imports
cabal configure -O0 --disable-library-profiling
cabal build --ghc-option=-ddump-minimal-imports
packunused

yields the following error:

packunused: user error (Saved package config file seems to be corrupt. Try re-running the 'configure' command.)

Can be reproduced on https://github.com/snowdriftcoop/snowdrift

Using:

packunused version 0.1.1.4
cabal-install version 1.22.4.0
using version 1.22.3.0 of the Cabal library
The Glorious Glasgow Haskell Compilation System, version 7.8.4

[MHova]

Same problem here using cabal-install version 1.23.0.0 (compiled/installed from HEAD) and GHC 7.8.3