patch applied (ghc): Fix computation of installed packages

[Simon Marlow]

On 24/09/2010 09:48, Simon Peyton Jones wrote:
> Fri Sep 24 01:47:37 PDT 2010  simonpj at microsoft.com
>    * Fix computation of installed packages
>
>    This is a follow-on to Simon's patch yesterday, developed
>    with him.  It cleans up the computation of how packages
>    are installed, and installs the right ones.

To clarify the current position with the DPH packages in the build system:

Short story: the DPH packages are required when validating, but are 
otherwise optional and are not installed.

Long(er) story:

In the HEAD, darcs-all still gets the DPH packages, vector, and 
primitive by default.  You can say

   ./darcs-all --no-dph

to avoid getting libraries/{dph,vector,primitive}, and GHC will build 
and install fine, although you can't validate.  (I do this in my working 
tree, because it saves time).

If you have dph-*, vector and primitive in your tree, then they are 
built but not installed.  Unless you are validating, in which case they 
WILL be installed, because validate builds a binary distribution and 
installs it, then uses the installed copy for testing.

Cheers,
	Simon