ranlib: has no symbols warning

When building CS-Map on OS X, ranlib gives the following error:

  ranlib: file: CsMap.a(CS_mfc.o) has no symbols

This is just a warning, and can be safely ignored.

building dynamic library

  gcc  -dynamiclib -g -arch i386 -lstdc++ -shared -Wl,-dylib -o csmap.dylib *.o

will build a dynamic library on OS X