https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104172
--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> --- That is what it should do. But it also has a mangling langhook and the backend uses it in the hope that it is a C++ FE langhook that will mangle the names like they were previously except with the s/u9__ieee128/U10__float128/g changes, but it of course doesn't do that.
