Can't find DPH

[colin-adams]

I added the following to the top of my module:

{-# LANGUAGE PArr, ParallelListComp #-}
{-# OPTIONS -fvectorise #-}

But when building I got:

GHC error in desugarer lookup in main:Board:
  Failed to load interface for `Data.Array.Parallel.Lifted.PArray':
    no package matching `dph-par' was found
ghc: panic! (the 'impossible' happened)
  (GHC version 6.11.20090317 for x86_64-unknown-linux):
	initDs IOEnv failure

Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug

I hadn't done anything in particular to try to install DPH, so this is probably a user error, but as the panic occurred, i felt duty-bound to report the bug as requested.

[simonpj]

What's gone wrong is that you need the DPH packages installed, else the DPH extensions won't work at all:  http://haskell.org/haskellwiki/GHC/Data_Parallel_Haskell.

Right, it's a bug that GHC crashes rather than giving a civilised error message.

Simon

[colin-adams]

That's what I thought, on both counts.

The instructions for installing the DPH packages fail at the first hurdle. Should I open a separate ticket for this, or just write an email on the ghc list?

[chak]

Replying to colin-adams:

That's what I thought, on both counts. The instructions for installing the DPH packages fail at the first hurdle. Should I open a separate ticket for this, or just write an email on the ghc list?

Just tell us. What is the first hurdle? As you report the error against 6.11, I am wondering how you obtained the compiler? Did you get it via darcs or as a nightly snapshot? In the latter case, I don't think there is a straight forward way of adding package DPH as I don't think we have snapshots for it.

If you get GHC from the darcs repo, getting dph is very easy. Just run

./darcs-all --dph get

in your local ghc repository. Then, build the compiler as usual.

[igloo]

As dph is now always built with GHC, there will not be an error due to it being absent. No response from submitter as to what the problem with installing dph was, and it presumably no longer applies anyway, so closing this ticket.