[CMake] dependency in custom command?

[King, Steven R]

> You don't need to do this. Since "my_module" is a CMake target, you can
> just use "my_module" instead of ${SO_LOCATION} in the custom_command
> below and CMake will figure out where the .so is on the disk> 

Hi Tyler  -- Substituting my_module did not work.  The copy fails.  Is this a cmake bug?

Thanks for the other pointers.