[Development] Question about QCoreApplicationData::*_libpaths

[Kevin Kofler]

Marc Mutz wrote:
> 1. We'd need to rename the copy, and how, without requiring template
>    aliases, would we then use one or the other (if we don't rename, we'll
>    run afoul of the ODR)

Just use good old #define:
#if HAVE_STD_OPTIONAL
#define Q_OPTIONAL std::optional
#elif HAVE_STD_EXPERIMENTAL_OPTIONAL
#define Q_OPTIONAL std::experimental::optional
#else
#define Q_OPTIONAL QtPrivate::optional
#endif

        Kevin Kofler