http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47260
--- Comment #12 from Craig Powers <craig.powers at gmail dot com> 2011-01-14 00:10:29 UTC --- Rather more tricky to get gcc built in mingw than I would have liked, but... it's all fixed. I can export with DLLEXPORT or with a .def file. Thanks for the quick fix!