https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105487
--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> --- When you say "if you set to a sysroot that doesn't contain any 32bit values, and thus doesn't contain the /sysroot/usr/lib directory at all but only has /sysroot/usr/lib64, then you can't compile GCC itself against that sysroot" can you please share the way you configure GCC (sources and build tree outside of the sysroot I presume) to compile it against such sysroot? Just for completeness and to be able to reproduce. While Andrew has a point, if the issue is simple enough to fix we should try.