[Haskell-cafe] ghc 6.8.2 issue

[Duncan Coutts]

On Mon, 2008-06-02 at 23:11 -0500, Galchin, Vasili wrote:
> at this point rebuild and install the "unix" package ...
> 
> vigalchin at ubuntu:~/FTP/Haskell/bytestring-mmap-0.2.0$ runhaskell
> Setup.lhs clean
> cleaning...
> vigalchin at ubuntu:~/FTP/Haskell/bytestring-mmap-0.2.0$ runhaskell
> Setup.lhs configure
> Configuring bytestring-mmap-0.2.0...
> vigalchin at ubuntu:~/FTP/Haskell/bytestring-mmap-0.2.0$ runhaskell
> Setup.lhs build
> Setup.lhs: error reading dist/setup-config; run "setup configure"
> command?
> 
> "dist/setup-config" is not being populated at the end. In your
> response below, are you saying that teh segfaults occur because ghc
> itself relies on the "unix" package?

Something like that yes.

You're running runhaskell Setup.lhs and that loads and runs code from
the Cabal library. The Cabal library depends on the process library
which depends on the unix library. So by replacing the same version of
the unix package you're breaking everything else which depends on it,
including Cabal and thus runhaskell Setup.lhs.

So the solution is to not do that. Don't re-install the exact same
version of any of the core libs that come with ghc. Adding new versions
is fine, replacing existing versions is not fine because it breaks all
the other packages that were already built against that package.

Duncan