Rationale for Using x86_64-linux-gnu with CentOS?

[Alexhuszagh]

Looking at the source code for cross, the only image that uses a CentOS base image is x86_64-unknown-linux-gnu, and the only relevant commit I can find for this addition is here, which has no explanation of the rationale.

Since CentOS 8 is EOL, and CentOS 7 is discontinued, it might be preferable to use Ubuntu as a base image for x86_64-unknown-linux-gnu, which would also simplify other issues like #517 (and the associated PR #591). If there is a good reason to keep CentOS as a base image, I would love to know, otherwise, I am happy to submit a PR to remove the CentOS logic and simplify package installation, image upgrades, etc.

[Emilgardis]

The rationale is that people are still using CentOS 7 (and by extension needs GLIBC 1.15), see #455 for example.

I can't find any info about CentOS 7 being unsupported now, if/when it is i think we'd gladly drop support for it

[Alexhuszagh]

Yeah maybe my wording was wrong: CentOS 8 is EOL and CentOS 7 is receiving security updates. I'll work around this to upgrade the Ubuntu base image, thank you.