Hi-- I'm new here and to these libraries so apologies in advance if I'm completely off by using sdcc 4.0-- my intention is to be helpful. I tried the process of setting up an environment with Cygwin64, sdcc 4.0 (latest release at the time of this writing), and these libraries. Apparently SDCC 4.0 has removed "sdcclib" completely after having deprecated it for some time. Therefore to get the build to work I had to edit the makefiles in libcv and libcvu directories as follows: 1) Change SDCCLIB = sdcclib to SDCCLIB = sdar 2) Where the makefiles would have problems on lines using SDCCLIB added the "-rc" flags. This line is one example: rm -f bin/libcv.lib; $(SDCCLIB) -rc bin/libcv.lib $(OBJ) After I made these changes things seemed to build just fine and I was able to compile these libs and compile and run the examples. Thanks Edit:. Sorry for a rookie mistake of reviving a really old thread rather than posting this under a newer update thread. If I could delete/move I would.