libtool has a bug/misfeature where it will override the -static-libstdc++ argument and still link dynamically to libstdc++. This is bad since we cannot guarantee that the libstdc++ in cenbuild will be compatible with what users have on their system. Issue was reported here: https://savannah.gnu.org/support/index.php?111184 We did a workaround in r41525 for bug 8485.
Upstream has now committed a fix that will be included in the next libtool version: https://git.savannah.gnu.org/cgit/libtool.git/commit/?h=development&id=a390f27ff13fd8bca3f43ab4721d8dc56c476acb We can remove our workaround and specify --enable-cxx-stdlib to configure instead after that fix is in place.
Let's try to backport this fix and get this all behind us.
Fixed, and we still have no runtime dependency on libstdc++.
