diff -U3 /tmp/cirrus-ci-build/contrib/pg_buffercache/expected/pg_buffercache.out /tmp/cirrus-ci-build/build/testrun/pg_buffercache/regress/results/pg_buffercache.out
--- /tmp/cirrus-ci-build/contrib/pg_buffercache/expected/pg_buffercache.out	2024-03-19 13:35:13.141982000 +0000
+++ /tmp/cirrus-ci-build/build/testrun/pg_buffercache/regress/results/pg_buffercache.out	2024-03-19 13:53:07.196003000 +0000
@@ -3,6 +3,7 @@
                    from pg_settings
                    where name = 'shared_buffers')
 from pg_buffercache;
+WARNING:  outfuncs/readfuncs failed to produce an equal rewritten parse tree
  ?column? 
 ----------
  t
@@ -12,12 +13,14 @@
         buffers_dirty <= buffers_used,
         buffers_pinned <= buffers_used
 from pg_buffercache_summary();
+WARNING:  outfuncs/readfuncs failed to produce an equal rewritten parse tree
  ?column? | ?column? | ?column? 
 ----------+----------+----------
  t        | t        | t
 (1 row)
 
 SELECT count(*) > 0 FROM pg_buffercache_usage_counts() WHERE buffers >= 0;
+WARNING:  outfuncs/readfuncs failed to produce an equal rewritten parse tree
  ?column? 
 ----------
  t
@@ -27,29 +30,36 @@
 -- having to create a dedicated user, use the pg_database_owner pseudo-role.
 SET ROLE pg_database_owner;
 SELECT * FROM pg_buffercache;
+WARNING:  outfuncs/readfuncs failed to produce an equal rewritten parse tree
 ERROR:  permission denied for view pg_buffercache
 SELECT * FROM pg_buffercache_pages() AS p (wrong int);
+WARNING:  outfuncs/readfuncs failed to produce an equal rewritten parse tree
 ERROR:  permission denied for function pg_buffercache_pages
 SELECT * FROM pg_buffercache_summary();
+WARNING:  outfuncs/readfuncs failed to produce an equal rewritten parse tree
 ERROR:  permission denied for function pg_buffercache_summary
 SELECT * FROM pg_buffercache_usage_counts();
+WARNING:  outfuncs/readfuncs failed to produce an equal rewritten parse tree
 ERROR:  permission denied for function pg_buffercache_usage_counts
 RESET role;
 -- Check that pg_monitor is allowed to query view / function
 SET ROLE pg_monitor;
 SELECT count(*) > 0 FROM pg_buffercache;
+WARNING:  outfuncs/readfuncs failed to produce an equal rewritten parse tree
  ?column? 
 ----------
  t
 (1 row)
 
 SELECT buffers_used + buffers_unused > 0 FROM pg_buffercache_summary();
+WARNING:  outfuncs/readfuncs failed to produce an equal rewritten parse tree
  ?column? 
 ----------
  t
 (1 row)
 
 SELECT count(*) > 0 FROM pg_buffercache_usage_counts();
+WARNING:  outfuncs/readfuncs failed to produce an equal rewritten parse tree
  ?column? 
 ----------
  t