List of oldest supported version of top 10 Linux Distros and their glibc version according to distrowatch.com.
Out of all versions with published EOLs, 2.12 is the oldest glibc still active, found in CentOS 6.8.
If CentOS 6 and 7 are eliminated, the oldest glibc is 2.23 in Ubuntu and Slackware.
Mint - 18.3 sylvia
- EOL: 2021-04
- glibc: 2.27
- EOL: 2023-04
- glibc: 2.27
- EOL: 2021-04
- glibc: 2.23
MX Linux - 17.1
- EOL: None (Based on Debian 9 which has no EOL yet)
- glibc: 2.24
- Notes: MX-16 is based on Debian 8 which is EOL 2020-05
Arch Linux - 2020.01.22
- EOL: Rolling release
- glibc: 2.30
Gentoo - 2020-01-22
- EOL: Rolling release
- glibc: 2.29
Slackware - 14.2
- EOL: None
- glibc: 2.23
- NOTE: No EOLs are published. 14.2 was released in 2016. Older versions have libc < 2.17.
Debian - 9 stretch
- EOL: None announced
- glibc: 2.24
Fedora - 30
- EOL: None announced
- glibc: 2.29
OpenSUSE - 15.1
- EOL: None announced
- glibc: 2.26
- EOL: 2020-11
- glibc: 2.12
- EOL: 2024-06
- glibc: 2.17
- EOL: None announced
- glibc: 2.28
FreeBSD - 10.3
- EOL: 2018-04
- glibc: N/A