Hi Robin, Expanding on Harald's response, the order on the command line for gcc and g++ is important. g++ /mylib/libA.a /mylib/libB.a myapp.o -o myapp This is what the linker does in processing from left-to-right: 1. libA.a -- don't need any symbols from there, ignore it. 2. libB.a -- don't need any symbols form there, ignore it. 3. myapp.o -- .o files are linked in wholesale, with outstanding symbols for A and B 4. Hmmm, myapp is missing A and B symbols. ERROR. Try putting the object files first, and the libraries in dependency order instead: g++ -o myapp myapp.o /mylib/libB.a /mylib/libA.a Since B depends on A (but not vice versa, fortunately), B should appear first. Although not the situation you are running into, sometimes there is a circular dependency between two libraries. One way to resolve that is to specify one library twice: g++ -o foo main.o /mylib/libAlpha.a /mylib/libBeta.a /mylib/libAlpha.a A better solution is to combine both libraries into one library. But that's not always feasible. HTH, --Eljay
