C++20 designated initializers must be specified in definition order, whereas they don't in C99. In your example, Point point = {.z = 2.0, .x = 1.0}; prod

C++20 designated initializers must be specified in definition order, whereas they don't in C99. In your example, Point point = {.z = 2.0, .x = 1.0}; produces a compilation error. This is annoying, but workable. And at least it's a compile-time error, rather than a bug that perniciously sneaks into production.