Aargh!  I can't build HEAD!

I get this:

./hadrian/build
Up to date
]0;Starting... ]0;Finished in 0.04s Error, file does not exist and no rule available:
  utils/hpc/hpc-bin.cabal
Build failed.

This is after

hadrian/build clean

./boot

./configure

I'm very stalled.  All my trees are borked.  Can anyone help?

Simon