From: Simon Marlow
But currently there is one problem with "GhcShared=YES": with this option, the stage-2 compiler gets linked dynamically but the corresponding inplace shell wrapper does not set (DY)LD_LIBRARY_PATH, thus ./inplace/bin/ghc-stage2 doesn't run at all. I could work around this by manually symlinking all the dynamic libraries to ./inplace/lib and setting (DY)LD_LIBRARY_PATH to there, but obvisouly there should be a solution better than this.
On Linux we link the binary using -rpath (I know OS X doesn't have -rpath). This is another issue we need to resolve before we can switch to a dynamically-linked GHCi.
Basically there's a fair bit to do to make a dynamic GHCi a reality, and before we can do anything there are some tricky decisions to make.
When you say OSX doesn't have -rpath, do you mean there's some problem with using -rpath on OSX? I have code that links to a 3rd-party library (libcudart.dylib) at runtime and it seems to use -rpath fine. This is with ghc-6.12.1. John