Yet again I have had to debug some truly weird behavior that was caused by bad variable name manipulation elsewhere in the code that looked like: ```cmake try_compile(result …) if (blah) set(${result} 0 CACHE INTERNAL …) else () set(${result} 1 CACHE INTERNAL …) endif () ``` which ends up setting a variable in the cache named `0` or `1` (based on the result). There should be a policy to deny setting any variable name that is also an integer to stop these kinds of things once and for all. Cc: @craig.scott @brad.king