https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109954
--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> --- If you override the --with-arch_32=x86-64 default then it's fine. -m32 -march=i386 will indeed produce code that runs on any i386. -m32 -march=i686 won't, nor will -m32 -march=x86-64 (which is the implicit default for an x86_64-pc-linux-gnu compiler).
