[CMake] Passing parameters via command prompt

[David.Karr at L-3COM.COM]

> 2008/11/26 Eric Noulard <eric.noulard at gmail.com>
> if you want to batch all those builds then may be you should
> always start from a pristine empty build dir, thus you won't have to
> bother on pre-existing cache since there won't be any.

I have a project where I create a pristine empty build dir every time I
want to try a new configuration (e.g. Release vs. Debug).  But I have to
confess that due to some other impediment I ran into regarding cache
variables--so many years ago that I've forgotten what it was--the setup
script for that project, before it calls cmake.exe with my chosen
options, DELETES the CMakeCache.txt file.  So I never have to wonder
whether a definition came from the cache or from somewhere else.

Every variable or property we have ever set on that project is specified
either by a CMakeLists.txt file or on the cmake.exe command line (placed
there by the script that calls cmake.exe); nobody configures that
project through the GUI.  Maybe that's why I've never noticed any
trouble caused by deleting the cache.

There's probably a more elegant solution, but since one line in a script
apparently fixed the problem, I haven't looked for another way.

David Karr