ClamAV requiring COMPAT_FREEBSD11

From: Andrea Venturoli <>
Date: Thu, 04 Aug 2022 10:49:11 UTC

I build clamav-0.105.1,1 (from quarterly branch) in Poudriere and I've 
always used it without problems.

Suddenly last night freshclam started dying on a few machines: it turn 
out it prints "bad system call", due to the lack of COMPAT_FREEBSD11 in 
the kernel.
Strangely it's been working with those kernels for years.

In any case, I'm trying to find a way out of this: I really wouldn't 
want to install a new kernel on a remote machine, considering the 
customers might be on the verge of closing for holidays, so I might not 
have the chance to go and fix it in case of troubles.
OTOH I can't leave ClamAV without DB updates for weeks, so I'm 
investigating if an alternative exists.

Why this requirement?
Is there a way to recompile ClamAV in order to let freshclam work 
without this kernel support?