https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78810
--- Comment #2 from rguenther at suse dot de <rguenther at suse dot de> --- On Fri, 16 Dec 2016, marxin at gcc dot gnu.org wrote: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78810 > > --- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> --- > Sorry, correct wording is that Ruby 2.3 does not survive its regression tests. Did you analyze why? vparser is unused here ... it looks like ruby is maybe trying to avoid a tail/sibling call here? That said, the optimization is perfectly valid.