GLIBC versions: https://launchpad.net/ubuntu/+source/glibc https://code.launchpad.net/ubuntu/+source/glibc
Get supported C++ standards by current installed GCC by one-line command:
gcc -v --help 2> /dev/null | grep -iv deprecated | grep "C++" | sed -n '/^ *-std=\([^<][^ ]\+\).*/ {s//\1/p}'