[CMake] Changing the the current generator in CMake GUI

[Bill Hoffman]

On 1/15/2016 2:41 PM, Greg Marr wrote:
> You can do both in the same solution/projects with the Microsoft fork
> of CMake, but it's not a general solution, and it doesn't handle
> different settings for 32 bit and 64 bit.  Because of that, they're
> "not pushing too hard" for it to be in mainline CMake.
>
> https://cmake.org/pipermail/cmake/2015-August/061346.html

Yes, and things like CMAKE_SIZEOF_VOID_P would not have valid values. 
However, if you want cmake builds to work, you should never change the 
generator in a CMakeCache.txt file, it is going to more often than not 
cause problems.  A build tree should be configured with one generator 
and if you need another generator you should use a different directory 
and a different build tree sharing the same source tree.

-Bill