Undefined symbol "setgroups@FBSD_1.8"

Hello,

Trying to build pkg within a newly created 
13.5-RELEASE-p5 1305000 c106ed332 amd64 git+https 2025-10-14 21:41:29
poudriere jail on a stable/15 host 
stable/15-n280668-998dd4a11a2b GENERIC amd64 1500500 1500500
errors at the configuring pkg stage with

[00:00:01] ===>  Configuring for pkg-2.3.1
[00:00:01] ==> Starting sccache
[00:00:01] ld-elf.so.1: /overlays/sccache/bin/sccache: Undefined symbol "setgroups@FBSD_1.8"
[00:00:01] ld-elf.so.1: /overlays/sccache/bin/sccache: Undefined symbol "setgroups@FBSD_1.8"
[00:00:01] *** Error code 1

If I rebuild and reinstall devel/sccache and ports-mgmt/sccache-overlay
the traditional way it makes no difference.

If I remove -O sccache from the command line the build runs normally.

I'm not altogether sure if this is a pkg problem, or ports infra, or
if it's sccache or even some other problem so if this is the wrong place 
then please advise.

I dimly recall on the lists something like FBSD_1.8 but can't remember
the context.
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