How do I check if one of multiple macros is defined in a single #ifdef?

c++ c-preprocessor conditional-compilation
beakr picture beakr · May 4, 2013 · Viewed 18.1k times · Source

I have some C++ code, and want to perform an action if the __APPLE__ or __linux macros are defined.

If I did it as a normal if conditional, it would be easy using ||:

if (something || something) { .. code .. }

But as of what I know there is no || operator for #ifdef statements. How would I check if __APPLE__ or __linux is defined using a single #ifdef statement?

Answer

john picture john · May 4, 2013

You can't in a single #ifdef would a single #if do instead?

#if defined(__APPLE__) || defined(__linux)

this also works if you prefer

#if defined __APPLE__ || defined __linux

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