[Cmake] LOAD_CACHE automatic exclude

[Julien Jomier]

Hi,

I'm having a problem using the LOAD_CACHE command.
I've one program which is setting some options (like GLUT_INCLUDE_DIR) but
these options are not required. Another program is using the first one so
I'm using the LOAD_CACHE command to avoid setting directories and libraries
again. 
The problem comes when the option has not been set in the first program
(GLUT_INCLUDE_DIR:PATH=GLUT_INCLUDE_DIR-NOTFOUND) then it's impossible to
set the same option in the second program because it always refers to the
cache of the first one. Of course if I exclude the option everything is
working well except the fact that I've to set the option in my second
program even if it's defined in the first one.

Is there any way to avoid this?

Thanks,

Julien