[CMake] Cross-compile?

[Gordon.Schumacher at seagate.com]

Is there somewhere that I can look for assistance setting up
a project that I will later cross-compile?  I am unsure how
to go about platform tests to allow cross-compilation.

For instance, if I'm at a Win32 host and compiling for Linux,
what will this do?

IF(WIN32)
   SET(mysources ${mysources} win32.c)
ENDIF(WIN32)
IF(UNIX)
   SET(mysources ${mysources} unix.c)
ENDIF(WIN32)

Does that do a platform check?