https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113765
--- Comment #6 from Jan Hubicka <hubicka at gcc dot gnu.org> --- Running auto-fdo without guessing branch probabilities is somewhat odd idea in general. I suppose we can indeed just avoid setting full_profile flag. Though the optimization passes are not that much tested to work with non-full profiles so there is some risk that resulting code will be worse than without auto-FDO.