Using `current_role`/`current_user` when logged as the `privileged_role` crashes

[steve-chavez]

Problem

When doing:

$ supautils-with-pg-16 psql -U postgres

-- these work as expected

postgres=# alter role current_user login;
ALTER ROLE

postgres=# set role authenticator;
SET
postgres=> alter role current_user login;
2025-01-31 16:24:11.273 -05 [1937471] ERROR:  "authenticator" is a reserved role, only superusers can modify it
2025-01-31 16:24:11.273 -05 [1937471] STATEMENT:  alter role current_user login;
ERROR:  "authenticator" is a reserved role, only superusers can modify it

But privileged_role crashes:

postgres=> set role privileged_role;
SET
-- same happenes for current_role
postgres=> alter role current_user login;
server closed the connection unexpectedly
        This probably means the server terminated abnormally
        before or while processing the request.
The connection to the server was lost. Attempting reset: 2025-01-31 16:24:44.210 -05 [1937454] LOG:  server process (PID 1937471) was terminated by signal 11: Segmentation fault
2025-01-31 16:24:44.210 -05 [1937454] DETAIL:  Failed process was running: alter role current_user login;
2025-01-31 16:24:44.210 -05 [1937454] LOG:  terminating any other active server processes
2025-01-31 16:24:44.211 -05 [1937483] FATAL:  the database system is in recovery mode
Failed.
The connection to the server was lost. Attempting reset: Failed.
!?> 2025-01-31 16:24:44.212 -05 [1937454] LOG:  all server processes terminated; reinitializing

It's minor since one can use the name of the actual role instead and changing privileged_role isn't allowed anyway.

postgres=> alter role privileged_role login;
2025-01-31 16:25:28.624 -05 [1937600] ERROR:  permission denied to alter role
2025-01-31 16:25:28.624 -05 [1937600] DETAIL:  Only superusers can alter privileged roles.
2025-01-31 16:25:28.624 -05 [1937600] STATEMENT:  alter role privileged_role login;
ERROR:  permission denied to alter role
DETAIL:  Only superusers can alter privileged roles.