https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108647
--- Comment #10 from Jakub Jelinek <jakub at gcc dot gnu.org> --- (In reply to Andrew Macleod from comment #9) > (In reply to Jakub Jelinek from comment #8) > > Unfortunately that would mean for the non-equality cases that if > > lhs.undefined_p () we don't return undefined but false (aka VARYING). > > Another option is to add those if (op?.undefined_p ()) return false; to both > > case BRS_TRUE: and case BRS_FALSE:. > > Well, if the LHS is undefined, (or even one of the operands) we are > typically in dead code or edge anyway.. I'm not sure it really matters? Ok, I'll test the patch then. > An alternate question as well is why is the threader even looking at this > impossible path. It should know that the branch can never be true I think range-op shouldn't assume nothing will call it with UNDEFINED ranges.
