Comment by wahern

GCC supports specifying endianness of structs and unions: https://gcc.gnu.org/onlinedocs/gcc-15.2.0/gcc/Common-Type-At...

I'm not sure how useful it is, though it was only added 10 years ago with GCC 6.1 (recent'ish in the world of arcane features like this, and only just about now something you could reasonably rely upon existing in all enterprise environments), so it seems some people thought it would still be useful.