5.67 inline functions in C99

The C99 keyword inline hints to the compiler that invocations of a function qualified with inline are to be expanded inline.

For example:

inline int max(int a, int b)
    return (a > b) ? a : b;    

The compiler inlines a function qualified with inline only if it is reasonable to do so. It is free to ignore the hint if inlining the function adversely affects performance.


The __inline keyword is available in C90.


The semantics of inline in C99 are different to the semantics of inline in Standard C++.

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