https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119408
--- Comment #19 from Xi Ruoyao <xry111 at gcc dot gnu.org> --- (In reply to Jakub Jelinek from comment #18) > _Float128 is definitely not for backward compatibility Sorry, I mean __float128. The problem here is we added __float128 as an alias of _Float128 for compatibility with existing code (of which the author only considered x86) and then added q/Q for such a compatibility too. And then we started to build libquadmath (Qiankang said so off-list) and libgfortran.spec started to refer it. It's not a good thing IMO, as we are duplicating sinl, cosl, ... from libm into sinq, cosq, ... from libquadmath, and we are making fortran programs redundantly depending on libquadmath. So IMO perhaps we should gate __float128 and q/Q behind a switch.
