Hi,
I'm from the Fedora MinGW project (http://fedoraproject.org/wiki/MinGW), and we are cross-compiling a number of Linux libraries, from Fedora targeting Windows. So I hope this is the right place to post a couple of libgsf patches which enable libgsf to be cross-compiled using Fedora MinGW cross-compiler.
The first patch changes the way that libbz2 / bzlib.h is detected. It is my understanding that both the library and the header file are needed in order to enable BZ2 support. However autoconf's AC_CHECK_LIB cannot be used to check whether -lbz2 works on its own on Windows, for rather complex reasons which are better explained by referring to this thread:
http://www.nabble.com/failed-tests-AC_CHECK_LIB-td19588119.html#a19589469
So the first patch replaces the pair of tests with an invocation of AC_LINK_IFELSE that tries to compile and link a program with both the header file and a call to the sentinel library function.
The second patch, considerably simpler, enables deprecated functions in glib, because otherwise G_WIN32_DLLMAIN_FOR_DLL_NAME isn't defined in gsf/gsf-utils.c. I'm not really familiar with what this macro does, and maybe a better solution is just to not use it if the macro isn't defined.
Here is our development repository: http://hg.et.redhat.com/misc/fedora-mingw--devel If we make any updates then you can get the latest specfile and patches by clicking 'manifest', then 'libgsf'.
Rich.