4 ms·

c++ has constexpr for this. a constexpr expression will be evaluated at compile time if the result is used in a constant expression (i.e. assignd to an enum con

c++ has constexpr for this. a constexpr expression will be evaluated at compile time if the result is used in a constant expression (i.e. assignd to an enum constant or a constexpr variable), or an error will be generated if it is not possible to do so (the expression does not fulfill the requirements to be constexpr).

krona 10y ago
working example: https://godbolt.org/g/EXdQx1 https://godbolt.org/g/EXdQx1
- TillE 10y ago
  Your example still gets calculated at compile time if you remove the constexpr. However, if you change -O3 to -O2, then there's a difference.