https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100733
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Note in older versions of GCC (8.x), disabling phiopt1 is needed instead of phiopt2.
pinskia at gcc dot gnu.org via Gcc-bugs Sun, 23 May 2021 10:21:43 -0700
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100733
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Note in older versions of GCC (8.x), disabling phiopt1 is needed instead of phiopt2.