I guess it would be a C linkage problem then. Have you got extern "C" {} around the exported symbols? Cheers, Stephan On Sat, Jan 16, 2010 at 7:21 PM, Yixun Liu <enjoywm at cs.wm.edu> wrote: > I do add test.c (see previous email). > If I change test.c to test.cxx, it works. I do not know why. >