https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60401
--- Comment #15 from Jonathan Wakely <redi at gcc dot gnu.org> --- (In reply to Jonathan Wakely from comment #14) > So I believe the problem is that you need to reconfigure libstdc++ with the > new glibc headers, you can't just drop them in later and expect an > already-built libstdc++ to work with them. Libstdc++ depends on glibc, so if > you update glibc (or fake doing so by using --sysroot to point at a new > glibc) then you need to rebuild libstdc++ too. After discussing this on IRC I'll make a change to support this use case, without needing to rebuild libstdc++ when glibc is updated.