I don't understand what 0002 patch does relative to the 0001 patch. Is 0002 to change the error messages from "schema variables" to "session variables" , in a separate commit to show that the main patch doesn't change regression results ? Could you add commit messages ?
I mentioned before that there's a pre-existing use of the phrase "session variable", which you should change to something else: origin:doc/src/sgml/ref/set_role.sgml: <command>SET ROLE</command> does not process session variables as specified by origin:doc/src/sgml/ref/set_role.sgml- the role's <link linkend="sql-alterrole"><command>ALTER ROLE</command></link> settings; this only happens during origin:doc/src/sgml/ref/set_role.sgml- login. Maybe "session variable" should be added to the glossary. The new tests crash if debug_discard_caches=on. 2021-12-20 16:15:44.476 CST postmaster[7478] LOG: server process (PID 7657) was terminated by signal 6: Aborted 2021-12-20 16:15:44.476 CST postmaster[7478] DETAIL: Failed process was running: DISCARD VARIABLES; TRAP: FailedAssertion("sessionvars", File: "sessionvariable.c", Line: 270, PID: 7657) #2 0x0000564858a4f1a8 in ExceptionalCondition (conditionName=conditionName@entry=0x564858b8626d "sessionvars", errorType=errorType@entry=0x564858aa700b "FailedAssertion", fileName=fileName@entry=0x564858b86234 "sessionvariable.c", lineNumber=lineNumber@entry=270) at assert.c:69 #3 0x000056485874fec6 in sync_sessionvars_xact_callback (event=<optimized out>, arg=<optimized out>) at sessionvariable.c:270 #4 sync_sessionvars_xact_callback (event=<optimized out>, arg=<optimized out>) at sessionvariable.c:253 #5 0x000056485868030a in CallXactCallbacks (event=XACT_EVENT_PRE_COMMIT) at xact.c:3644 #6 CommitTransaction () at xact.c:2178 #7 0x0000564858681975 in CommitTransactionCommand () at xact.c:3043 #8 0x000056485892b7a9 in finish_xact_command () at postgres.c:2722 #9 0x000056485892dc5b in finish_xact_command () at postgres.c:2720 #10 exec_simple_query () at postgres.c:1240 #11 0x000056485892f70a in PostgresMain () at postgres.c:4498 #12 0x000056485889a479 in BackendRun (port=<optimized out>, port=<optimized out>) at postmaster.c:4594 #13 BackendStartup (port=<optimized out>) at postmaster.c:4322 #14 ServerLoop () at postmaster.c:1802 #15 0x000056485889b47c in PostmasterMain () at postmaster.c:1474 #16 0x00005648585c60c0 in main (argc=5, argv=0x564858e553f0) at main.c:198