[CMake] Create library and executable with libraries but no source files

[Alexander Neundorf]

On Friday 14 November 2008, s.bedouet at voila.fr wrote:
> Hi,
> main.c is not necessary for diab compiler (microcontroller) (add_executable
> generates an .elf file thanks to my toolchain file). I agree with you for
> executable and gcc but what about library ?

I don't really understand you here.
Anyway, how about just creating an empty C-file so cmake doesn't complain 
anymore ?
You could do this also automatically using configure_file().

Alex