The changes to libc that caused its major number to be bumped to version 13
will break too many things just before a release. Hence the changes will
be made in another way, which keeps the major number of libc at 12.

In the meantime, try to avoid libc version 13. It will go away. If you
have not already built it, refrain from doing so. If you have built it,
instructions on how to revert will follow later.

Sorry for the inconvenience,

- Frank