BUG #17304: Test failure with -fsanitize=undefined

The following bug has been logged on the website:

Bug reference: 17304
Logged by: Martin Liška
Email address: marxin(dot)liska(at)gmail(dot)com
PostgreSQL version: 14.1
Operating system: Linux
Description:

F="-fsanitize=undefined -g -O2" && export CFLAGS="$F" && export
CXXFLAGS="$F" && export LDFLAGS="$F" && ./configure
...
make check
...

cat /home/marxin/Programming/postgres/src/test/regress/regression.diffs
diff -U3
/home/marxin/Programming/postgres/src/test/regress/expected/errors.out
/home/marxin/Programming/postgres/src/test/regress/results/errors.out
---
/home/marxin/Programming/postgres/src/test/regress/expected/errors.out 2021-08-16
18:20:32.157439777 +0200
+++
/home/marxin/Programming/postgres/src/test/regress/results/errors.out 2021-11-30
15:05:59.927802757 +0100
@@ -17,6 +17,7 @@
-- SELECT
-- this used to be a syntax error, but now we allow an empty target list
select;
+print.c:969:4: runtime error: null pointer passed as argument 1, which is
declared to never be null
--
(1 row)

diff -U3
/home/marxin/Programming/postgres/src/test/regress/expected/union.out
/home/marxin/Programming/postgres/src/test/regress/results/union.out
---
/home/marxin/Programming/postgres/src/test/regress/expected/union.out 2021-11-11
15:59:29.507314173 +0100
+++
/home/marxin/Programming/postgres/src/test/regress/results/union.out 2021-11-30
15:06:00.667797080 +0100
@@ -936,6 +936,7 @@
-- Check behavior with empty select list (allowed since 9.4)
--
select union select;
+print.c:969:4: runtime error: null pointer passed as argument 1, which is
declared to never be null
--
(1 row)

diff -U3
/home/marxin/Programming/postgres/src/test/regress/expected/alter_table.out
/home/marxin/Programming/postgres/src/test/regress/results/alter_table.out
---
/home/marxin/Programming/postgres/src/test/regress/expected/alter_table.out 2021-11-11
15:59:29.495314262 +0100
+++
/home/marxin/Programming/postgres/src/test/regress/results/alter_table.out 2021-11-30
15:06:06.555751926 +0100
@@ -1530,6 +1530,7 @@
alter table atacc1 drop d;
alter table atacc1 drop b;
select * from atacc1;
+print.c:969:4: runtime error: null pointer passed as argument 1, which is
declared to never be null
--
(1 row)