checking upper bounds on base

[Duncan Coutts]

Hi Ross,

I'd like to get Hackage using the new check for base being bounded
above. I think it'll make a big difference when it comes to future
ghc/base upgrades. The last one was papered over by cabal-install
defaulting to base 3 when the package author did not specify otherwise.
That will not work forever.

You mentioned in the ticket that we need to have base strictly following
the PVP. That's true of course. I'm assured by the GHC hackers that
they're committed to the PVP. The reason for bumping 4.0 -> 4.1 is being
looked at but their first guess is that it was the change in GHC's
finaliser semantics (which did indeed break a couple programs).

For the practical issues:

I'll can send announcement to the haskell (+cafe) mailing list
explaining what people have to do and the rationale.

There have been a number of changes in the Cabal lib recently, it may be
that you prefer to just pull the checking patch for the hackage-scripts
rebuild, rather than everything. OTOH, I don't expect any problems from
pulling everything as the changes have been mostly in the build system
side of things.

What do you think? Is this a sane plan?

Duncan