I tried two different things to get sources that would compile but it seems that _obj is an empty folder. When I closed the repository and copied the make file to the source folder and attempted to run it I get the following error...
root@archive:~/mupen64plus-bundle-linux32-1.99.4/GlideNew/mupen64plus-video-glide64/src# make all
make: *** No rule to make target
_obj/osal_dynamiclib_unix.o', needed bymupen64plus-video-glide64.so'. Stop.
I also tried the .tar.gz file that can obtained from the "Get Source" at the right side of the page and that archive doesn't have a _obj folder at all. Do you have the sources that are supposed to be in this folder? Feel free to e-mail me as I don't have a bitbucket account raymondboettcher(at)yahoo(dot)com.