https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96016
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> --- If long double is 128bit fp already, then glibc has full support of it. So you dont need libquadmath at all. It is only there if long double is not 128bit long double and glibc does not have support for the __float128 type.