https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80741
--- Comment #2 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> --- My initial looks are seeing a DTIO related frontend issue but this is not causing the regression as far as I can tell. I have looked at several other intervening patches and don't see anything obvious, so I am starting a regression hunt. If anyone beats me to it, report here, I will be monitoring this bug. BTW, thanks James for the report. Much appreciated.