We've had unbelievable problems getting past this ridiculous 'unable to load object file or shared library libedit.so.0' error when attempting to build the 6.10.1 source tree. We initially just built editline in a user directory and attempted to manipulate environment variables to help the linker (e.g. setting LIBRARY_PATH, LD_LIBRARY_PATH, and CPATH) - but this did no good. We then just installed the editline package so it's available globally and the libraries (specifically libedit.so.0) live in /usr/local/lib, so it should be found with no problem. Not so for ghc - same error. We're running this on Red Hat. I'm part of a research group at Northwestern University that is exploring the use of ghc and associated libraries for some upcoming projects. It's a shame that this is so difficult to even compile/install, and nobody seems to be able to figure out what's wrong.