Cabal not installing dependencies when needing profiling libraries?

Question

I want to compile my program with profiling, so I run:

$ cabal configure --enable-executable-profiling
...
$ cabal build
...
    Could not find module \'Grap         


        

Answer 1

From a comment by Tom Lokhorst:

I do hope someone will come along with a better answer, one that would not require me to reinstall the complete Haskell Platform manually next time.

For future visitors:

The task of installing profiling versions of all installed libraries has become less of a chore, cabal (cabal-install) now keeps track of what was installed using it in the world file in the .cabal directory (on linux, that would be $HOME/.cabal, on Windows something like C:\Users\%YOU%\AppData\Roaming\cabal\, on OSX ??).

So after enabling profiling in the config file (in the same directory), and clearing GHC's package database (you can find the locations of the global and user db per ghc-pkg list nonexisting; remove the cabal-installed packages from the global database with ghc-pkg unregister packagename if you have any, rename or delete the entire user db - this is necessary because the world file only tracks explicitly installed packages, not their dependencies), installing everything with profiling support should work as follows:

$ cabal install --reinstall world --dry-run

First run with --dry-run to check for problems before actually reinstalling anything. If it would reinstall boot packages like process or directory, that's a bad sign, if you don't know how to handle it, ask on the #haskell IRC channel, one of the mailing lists, or here for guidance. If it fails to find a consistent install plan due to new versions on hackage of some packages which are incompatible with each other, that can usually be solved by editing the world file and constraining allowable versions of some packages.

Then, if you are optimistic that nothing will badly break,

$ cabal install --reinstall world

and have a nice pot of tea while GHC is busy compiling.