> Does 'ldd shared.so' show any dependency on libboost_thread.so? (I'm > assuming no) > > Have you tried fixing the link line so that the libraries are listed > after the objects that depend on them? > > outputdir/shared.so: $(OBJECTS) > $(CPP) -o $@ $(OBJECTS) -Wl,--whole-archive outputdir/archive.a > -Wl,--no-whole-archive -L/path/to/boost -L/path/to/others - > lboost_python -lboost_thread -lboost_regex -fPIC -shared No, I had not tried this yet. Frankly, I'd forgotten about how important it is (this comes from the last 4 or 5 years being in nothing but Windows and using Visual Studio). I have tried your suggestion above, changing the order, and I can now import the python module without error. Many thanks Jonathan. Andy