I'm currently trying to compile all of boost on OS X (10.3.7), using TOOLS=darwin. I already read about the problems with xml_grammar, so I just added: #ifdef NDEBUG template class basic_xml_grammer<char>; #endif //NDEBUG This at least lets the compilation finish. And I'm not using boost::serialization yet. Hopefully Apple will get a fix (I am compiling with their latest build 1671). But I'm running into another problem during the link stage of the test libraries "libboost_unit_test_framework.dylib" It happens in both debug and release builds, I get: ld: Undefined symbols: init_unit_test_suite(int, char**) I found this function defined in auto_unit_test.hpp, and referenced in some of the .cpp files. Now, I'm guessing that this might be intentionally undefined, so that when you bind to the dynamic library, you define your own initialization (probably through a macro), and the library uses that. Has anyone else had this problem? I tried looking through the regression tests, but I haven't found anything that looks like this problem. I saw this post on the mailing list: http://thread.gmane.org/gmane.comp.lib.boost.user/6489 But there were no follow-ups, so I decided to re-post. Is this just a problem with dynamic libraries on Mac, that they can't have undefined symbols? Or is it something else? If it just means that you can only use the static library, that's fine. But why is it compiling the dynamic ones on Mac if they won't succeed? Thanks, John =:->