Re: REINDEX INDEX results in a crash for an index of pg_class since 9.6

Michael Paquier <michael@paquier.xyz> writes:
> Fujii-san has sent me a report offline about REINDEX.  And since 9.6,
> trying to REINDEX directly an index of pg_class fails lamentably on an
> assertion failure (mbsync failure if bypassing the assert):

So ... I can't reproduce this on HEAD.  Nor the back branches.

regression=# \d pg_class
...
Indexes:
    "pg_class_oid_index" UNIQUE, btree (oid)
    "pg_class_relname_nsp_index" UNIQUE, btree (relname, relnamespace)
    "pg_class_tblspc_relfilenode_index" btree (reltablespace, relfilenode)

regression=# reindex index pg_class_relname_nsp_index;
REINDEX
regression=# reindex index pg_class_oid_index;
REINDEX
regression=# reindex index pg_class_tblspc_relfilenode_index;
REINDEX
regression=# reindex table pg_class;         
REINDEX
regression=# reindex index pg_class_tblspc_relfilenode_index;
REINDEX

Is there some precondition you're not mentioning?

            regards, tom lane