https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78885
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Gcac is always collect when ggc_collect is called so yes it will be slow as gc collecting is slow due to having to mark and sweep over huge amounts of memory and there are many calls to ggc_collect now. Each new pass gets one new call.
