That is not the current (stable). Most of the items in that area are tests versions.
This might help:
My gcc on Debian 11 is:
jon@deb11HPZ:~$ gcc --version
gcc (Debian 10.2.1-6) 10.2.1 20210110
Copyright (C) 2020 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
OK, i see. If you have setup a IPFire building environment, it might be a possibility to make a complete build, change into chroot and compile an OSSEC agent for a binary installation → https://www.ossec.net/docs/docs/manual/installation/installation-binary.html and import it to your dedicated machine. I did that long time ago and it simply works at that time but for a specific installation a longer way needs to be done.
Not sure if it makes sense to post it here but there are some building instructions out there → ummeegge / ossec-wazuh · GitLab which where/are in fact not complete nor actual and also, as already mentioned, long time ago but may it can give you an idea for your project ?!