Why doesn't this work (It's failing the assert...that I don't want it to execute)?
#define OS_MACOSX 0
#if defined(OS_MACOSX)
fructose_assert(1==2);
#endif
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Brian Tompsett - 汤莱恩
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You define something, then check if it is defined, and wonder why that yields true? I don't get why you are confused. – Baum mit Augen Dec 15 '16 at 17:50
1 Answers
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Because you're using the wrong test.
OS_MACOSX IS defined... to 0. You asked if it is defined. Ask instead if it is set:
#if OS_MACOSX
fructose_assert(1==2);
#endif
If it is defined to something that evaluates to zero, or not defined at all, the #if will skip over the code. Any non-zero value, and the #if condition is met and the code is compiled.
See this related question: Why do people use #ifdef for feature flag tests?
