&spall So, I decided to go spelunking in gdb today. Learned many things.
Auto-tracing gdb is a pain in the ass, because gdb's thread pool starts before main. Very C++, such wow.
(this trace video doesn't have the ~10+ other threads GDB spun up before main started, more research needed to inject spall earlier)

When GDB does symbol resolution, it runs resolvers for a pile of languages, one after another, for each symbol.