https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69725
--- Comment #13 from Markus Trippelsdorf <trippels at gcc dot gnu.org> --- (In reply to Richard Biener from comment #12) > Confirmed. I suspect it's coverage mismatch errors causing the issue. No. The file in question changes between stages as shown in comment 10. PGO of course can not work in this case.