The issue turned out to be the bug3333.sql test needed to be updated. Verified that the failing query (q5) from bug3333 returned same results on MDB as on Columnstore and proceeded to update test.

Builds verified: 1.2.6-1, 1.4.4-1, 1.5.0-1 source

against regression test branches develop-1.2, develop-1.4, develop, respectively
1.2.6-1

/root/ColumnStore/buildColumnstoreFromGithubSource/mariadb-columnstore-server
commit d3294cf9c18663673c62532dddaa11369ba184d0
Merge: 2ef719d c5be945
Author: Andrew Hutchings <andrew@linuxjedi.co.uk>
Date: Thu Oct 31 15:06:48 2019 +0000

commit 4db1eb1f71aaafd375a332c55d72a80c8d14f145
Merge: d5179a1 bb2ad91
Author: Patrick LeBlanc <43503225+pleblanc1976@users.noreply.github.com>
Date: Fri May 1 09:33:48 2020 -0500

1.4.4-1

/root/ColumnStore/buildColumnstoreFromGithubSource/server
commit 00abe03ad1da3719e06f7112000a331ee2b6786a
Author: Patrick LeBlanc <43503225+pleblanc1976@users.noreply.github.com>
Date: Wed Apr 29 10:00:54 2020 -0500

/root/ColumnStore/buildColumnstoreFromGithubSource/server/engine
commit 2b67ac7f3537bd4b4d132c8a6c3a53e4cc63f4a1
Merge: beaac49 23d65dc
Author: benthompson15 <ben.thompson.015@gmail.com>
Date: Tue Apr 28 15:40:45 2020 -0500

1.5.0-1

/root/ColumnStore/buildColumnstoreFromGithubSource/server
commit 25eb50d6c002e987e2d240402391549d408c18d9
Author: Alexey Bychko <abychko@gmail.com>
Date: Thu Apr 23 12:36:13 2020 +0700

commit 6ad38ccc28d31a099d052e5de827543808843a3c
Merge: 658abae bb3e76b
Author: benthompson15 <ben.thompson.015@gmail.com>
Date: Fri Apr 24 14:31:09 2020 -0500