https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61321
--- Comment #12 from Markus Trippelsdorf <trippels at gcc dot gnu.org> --- _ZSt7forwardIRKZN5Write14DataMapGrammarISt20back_insert_iteratorISsEEC4EvEUlRT_E_EOS5_RNSt16remove_referenceIS5_E4typeE still recurses endless, even with your patch applied.
