FWIW, s/krb5_des_string_to_key/krb5_string_to_key/ gets things working for me
I also removed files/patch-configure since it just changes some instances to another function that doesn't exist.
I'm not clear on why configure checks for a function the source doesn't use though. Just for library detection maybe?
Created attachment 211840 [details]
The attached patch updates the check in configure to look for a symbol that exists in all three versions of krb5 that currently exist in the ports tree.
The check is indeed for library detection, and worked correctly for krb5 < 1.18.
For a bit of the history on the patch-configure, see https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=227680 and https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=234740#c3
A commit references this bug:
Date: Sat Feb 22 18:24:30 UTC 2020
New revision: 526846
Fix the build with the latest krb5 port
Submitted by: Corey Halpin <email@example.com> (maintainer)