unison doesn't build on Catalina

[nigelhorne (Nigel Horne)]

I have updated to Catalina and at the same time unison failed to update. I can't be sure, but I suspect that this is not a coincidence.

I get this:

--->  Attempting to fetch unison-2.51.2_2+gtk.darwin_19.x86_64.tbz2 from https://packages.macports.org/unison
--->  Attempting to fetch unison-2.51.2_2+gtk.darwin_19.x86_64.tbz2 from http://ywg.ca.packages.macports.org/mirror/macports/packages/unison
--->  Attempting to fetch unison-2.51.2_2+gtk.darwin_19.x86_64.tbz2 from http://fco.it.packages.macports.org/mirrors/macports-packages/unison
--->  Building unison
Error: Failed to build unison: command execution failed
Error: See /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_net_unison/unison/main.log for details.
Error: Follow https://guide.macports.org/#project.tickets to report a bug.
Error: Processing of port unison failed

[nigelhorne (Nigel Horne)]

/opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_net_unison/unison/main.log

[mf2k (Frank Schima)]

Duplicate of #58852.