https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70323
--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> --- I'm still getting the second error even with latest trunk, so can only partially reproduce it: pr70323.C:7:37: in constexpr expansion of ‘overflow_if_1(1)’ pr70323.C:7:39: error: overflow in constant expression [-fpermissive] constexpr bool i1_1 = overflow_if_1 (1); // error expected ^ I agree that r233878 introduced the only regression I can reproduce here. No revision between r234100 and r234359 emits no errors (checked all of them), so you must have had some local changes in.