[CMake] call already made makefile

[SK]

On Fri, Nov 5, 2010 at 1:04 PM, Alan W. Irwin <irwin at beluga.phys.uvic.ca> wrote:
> I agree the above idea should work, but dropping add_custom_command
> completely and moving the COMMAND to add_custom_target instead (and
> dropping all file DEPENDS for the custom target) is even a simpler way
> to insure COMMAND gets executed every time the custom target is
> built.

Yes it always runs, but there is no "output" from add_custom_target.
When the external makefile produces an output needed by some larger
dependency chain, then add_custom_command is the only way.