make tags in GHC build

[John Pybus]

Hi,

The documentation suggests that I should be able to do "make tags" to 
get a vim tags file for the GHC code.

http://hackage.haskell.org/trac/ghc/wiki/Building/StandardTargets

When doing this on a recent GHC checkout I get:

ghctags: user error (You need to re-run the 'configure' command. The 
version of Cabal being used has changed (was Cabal-1.9999, now 
Cabal-1.11.0). Additionally the compiler is different (was ghc-6.12, now 
ghc-7.1) which is probably the cause of the problem.)
make[1]: *** [tags_compiler] Error 1
make: *** [tags] Error 2

rerunning ./configure doesn't make any difference. (building on Ubuntu 
10.04 amd64, with haskell platform packages)

Does anyone know how to get make tags to work?

Thanks,
John