You need to graft: when building a package, the output hash depends on the inputs, sources and instructions, so even if the content of the lib output does not change, its store path does, leading to a rebuild.

Le 19 mars 2021 06:25:31 GMT-04:00, "Léo Le Bouter via Bug reports for GNU Guix" <bug-guix@gnu.org> a écrit :
CVE-2021-27928	04:15
A remote code execution issue was discovered in MariaDB 10.2 before
10.2.37, 10.3 before 10.3.28, 10.4 before 10.4.18, and 10.5 before
10.5.9; Percona Server through 2021-03-03; and the wsrep patch through
2021-03-03 for MySQL. An untrusted search path leads to eval injection,
in which a database SUPER user can execute OS commands after modifying
wsrep_provider and wsrep_notify_cmd. NOTE: this does not affect an
Oracle product.

From https://jira.mariadb.org/browse/MDEV-25179 it looks like 10.5.9
fixes it for us since we package 10.5.8 currently.

However:

$ ./pre-inst-env guix refresh -l mariadb
Building the following 552 packages would ensure 1047 dependent
packages are rebuilt:
[..]

Is it possible to graft mariadb you think? I am thinking this issue
doesnt need updating of the "lib" output which is what's causing the
high number of dependents AIUI. I am not sure we could actually update
individual outputs right now though. Might be a good idea to split the
packages for the future.

Léo