[Bug c++/84744] cannot use glibc 2.27 with gcc 7.3

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84744

--- Comment #8 from Jonathan Wakely <redi at gcc dot gnu.org> ---
You need to recompile gcc telling it to use the new glibc.

When GCC is built it creates fixed dependencies on the C library. You can't
just point it to a new libc and expect it to work. A new C library needs a new
compiler as well.

So build GCC (see https://gcc.gnu.org/wiki/InstallingGCC for a starting point)
and add --with-native-system-header-dir=/FaF/glibc/include/ to the configure
options.