[Swan] libreswan 3.21 error?

[D. Hugh Redelmeier]

| From: Paul Wouters <paul at nohats.ca>

| On Sun, 24 Sep 2017, Charles Van Dusen wrote:
| 
| > Sep 24 11:08:05 rpiNC pluto[8381]: ABORT: ASSERTION FAILED: dns_ctx != NULL
| > (in unbound_event_init() at unbound.c:188)
| > 
| > Sep 24 11:08:05 rpiNC pluto[8381]: ABORT: ASSERTION FAILED: dns_ctx != NULL
| > (in unbound_event_init() at unbound.c:188)
| 
| Your libunbound is too old. Please upgrade to at least 1.5.x or
| recompile libreswan with USE_DNSSEC=false

This is a horrible diagnostic.  Can we do better?

(This just came up on IRC but the guy wandered off before anyone could
answer.)