[CMake] How to compare booleans

[David Cole]

EQUAL is meant for exact numeric equal comparison (i.e. -- works with
numbers only, not meant to work with booleans)

One possibility is:

if(_COMPILE_RESULT)
  set(_COMPILE_RESULT 1)
else()
  set(_COMPILE_RESULT 0)
endif()

if(SHOULD_COMPILE)
  set(SHOULD_COMPILE 1)
else()
  set(SHOULD_COMPILE 0)
endif()

if(_COMPILE_RESULT EQUAL SHOULD_COMPILE)
...

Or make new tmp vars if you can't adjust the vars in-the-same-name like that...


On Thu, Aug 2, 2012 at 6:49 PM, Rolf Eike Beer <eike at sf-mail.de> wrote:
> I have 2 variables that hold boolean values. One is the result of a
> try_compile() and the other has the expected outcome. Now I want to check if
> the expectation is correct, so I tried:
>
> if (_COMPILE_RESULT EQUAL SHOULD_COMPILE)
>
> Which works if both are true or different, but the result is "false" if both
> variables are false, too. I played around with expanding the variables or
> quoting, but no change. The only way I got the expected result was this:
>
> if (_COMPILE_RESULT EQUAL SHOULD_COMPILE OR (NOT _COMPILE_RESULT) EQUAL (NOT
> SHOULD_COMPILE)
>
> This is not really what I would have expected. Is there a less ugly way to get
> the expected result?
>
> Eike
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