[CMake] Overriding default values

[James Bigler]

Perhaps I should be more clear as to what I'm trying to do.

Is there a way to determine if CMake has been configured once for a given project?

CMake obviously defines defaults for certain variables.  For example:

  CMAKE_CXX_FLAGS_RELEASE          -O2

Now, as the user, I can change this value with ccmake to be whatever I want, and 
CMake will not change that ever once it has configured once.

All I want to do is offer a different default option that has the same 
properties.  Once CMake configures the first time, CMake doesn't touch the value 
again.

Thanks,
James