Todd Mitchell wrote: > do I have to? What you can try: rm random_map/reader.c cvs update random_map/reader.c touch random_map/reader.c And try to recompile and see if that works. My guess is what happened is that the date for reader.l was later than that of reader.c, so it decided to rebuild reader.c. However, the lex/flex you have on your system requires and external library or something. the reader.c/reader.l have not changed in more than a year, so there certainly isn't any issue with the files themselves.