https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84744
--- Comment #5 from Marc Glisse <glisse at gcc dot gnu.org> --- That's not how you use a different glibc. If you look at the include order printed by -v, it has to remain in that order (libstdc++ before glibc, in particular), whereas you are adding your glibc in front. Best would be to recompile gcc, which has the added advantage that it will be able to take advantage of the new features in the new glibc this way.
