The OpenSMTPD portable version from https://github.com/OpenSMTPD/OpenSMTPD works fine on Slackware64 current with OpenSSL 1.1.1c and gcc 9.2
It took me a while to get it to work though. I first downloaded the "current" portable version from https://opensmtpd.org/archives/opensmtpd-6.4.2p1.tar.gz And I got errors very similar to those of Denis Fateyev on Fedora 30. Next I downloaded the portable version from github.com and found that autoconf had not been run and this was no good. Finally I discovered the post on the mailing list which mentioned the "bootstrap" script and then I was able to download and build the portable version from git. The code shows version "6.6.0-portable". It runs fine on Slackware64 current and I'm happy that it now works with OpenSSL 1.1 Regards, Richard Narron
