https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99339
--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> --- So we could try to lower even va_start/end to expose the va_list meta fully to the middle-end early which should eventually allow eliding it. That would require introducing other builtins/internal fns to allow referencing the frame or the incoming arg registers by number.
