More specifically, I want to link a haskell .o file into a project I create on OS X using Xcode, but the answer to the gcc question should do it. I've followed the simple "calling haskell from C" example from HaskellWiki, and it works as advertised when compiled as advertised with gcc. However, I'm looking toward writing OS X programs with Xcode and the standard Mac interface, calling some functions written in Haskell. Consequently, I want to compile and link using the mac Xcode IDE, which uses gcc. Seems like the thing that GHC puts in must be include .h files and libraries. But which ones? I think I ran across the answer to this in my browsing, but can't find it again. Can someone point me in the right direction? Thanks, John Velman