BUG #16041: Error shows up both in pgAdmin and in Ruby (pg gem) - Segmentation fault

The following bug has been logged on the website:

Bug reference: 16041
Logged by: Mark Siemers
Email address: mark(dot)siemers(at)gmail(dot)com
PostgreSQL version: 12.0
Operating system: Mac OS X Mojave 10.14.6
Description:

For further details (including crash report) see bugs filed with
third-parties:
Ruby - https://bugs.ruby-lang.org/issues/16239
pgAdmin 4 - https://redmine.postgresql.org/issues/4813

The speculation from a ruby maintainer is there is an issue with GSS
authentication on OS X.

Snippet of stack trace below:
7 ??? 0x0000000200000000 0 + 8589934592
8 com.apple.security 0x00007fff3f57c059 invocation function
for block in
Security::KeychainCore::StorageManager::tickleKeychain(Security::KeychainCore::KeychainImpl*)
+ 287
9 libdispatch.dylib 0x00007fff5fd6d63d
_dispatch_client_callout + 8
10 libdispatch.dylib 0x00007fff5fd79129
_dispatch_lane_barrier_sync_invoke_and_complete + 60
11 com.apple.security 0x00007fff3f57be47
Security::KeychainCore::StorageManager::tickleKeychain(Security::KeychainCore::KeychainImpl*)
+ 441
12 com.apple.security 0x00007fff3f37cae2
Security::KeychainCore::KCCursorImpl::next(Security::KeychainCore::Item&) +
230
13 com.apple.security 0x00007fff3f523c98
Security::KeychainCore::IdentityCursor::next(Security::SecPointer<Security::KeychainCore::Identity>&)
+ 192
14 com.apple.security 0x00007fff3f545f2f
SecIdentitySearchCopyNext + 145
15 com.apple.security 0x00007fff3f550956
SecItemCopyMatching_osx(__CFDictionary const*, void const**) + 238
16 com.apple.security 0x00007fff3f553fc5 SecItemCopyMatching +
316
17 com.apple.Heimdal 0x00007fff4feae830 0x7fff4fe5c000 +
337968
18 com.apple.Heimdal 0x00007fff4fead35e hx509_certs_find +
67
19 com.apple.Heimdal 0x00007fff4fe88a6c _krb5_pk_find_cert +
246
20 com.apple.GSS 0x00007fff364dbd8e
_gsspku2u_acquire_cred + 386
21 com.apple.GSS 0x00007fff364cb0d8 gss_acquire_cred +
523
22 libpq.5.dylib 0x0000000112b4b77d
pg_GSS_have_cred_cache + 54
23 libpq.5.dylib 0x0000000112b39edf PQconnectPoll +
6377
24 libpq.5.dylib 0x0000000112b36f8b connectDBComplete +
232
25 libpq.5.dylib 0x0000000112b37112 PQconnectdb + 36
26 pg_ext.bundle 0x000000011157ab01
gvl_PQconnectdb_skeleton + 17
27 ruby 0x000000010f1dfff9 call_without_gvl +
185
28 pg_ext.bundle 0x000000011157aadd gvl_PQconnectdb +
45
29 pg_ext.bundle 0x000000011157fcb9 pgconn_init + 121
30 ruby 0x000000010f221b1c vm_call0_body + 604