https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85478
--- Comment #7 from Andreas Krebbel <krebbel at gcc dot gnu.org> --- The cross from comment #6 did not trigger the problem because I accidentally built it with --disable-checking. Dropping this and adding --with-long-double-128 triggers the ICE on a full cross as well as on a cross without sysroot.