[to3m]

Ha... yes, a good point. That's a reasonable reason not to generate the load, and stupid me for not noticing. What's also dumb is that my eyes just glossed over the ud2 instruction that both put in main too. The program (not unreasonably) won't even run properly anyway.

gcc does seem to be keener than clang to chop bits out - I think I prefer clang here. But let's see how I feel if I encounter this in anger in a non-toy example ;) I must say I'm still a bit suspicious, but I can't really argue that this behaviour is especially surprising here, or difficult to explain.