pgsql: Fix use-after-free bug with event triggers in an extension scrip
Fix use-after-free bug with event triggers in an extension script
ALTER TABLE commands in an extension script are added to an event
trigger command list; but starting with commit b5810de3f4 they do so in
a memory context that's too short-lived, so when execution ends and time
comes to use the entries, they've already been freed.
(This would also be a problem with ALTER TABLE commands in a
multi-command query string, but these serendipitously end in
PortalContext -- which probably explains why it took so long for this to
Fix by using the memory context specifically set for that, instead.
Backpatch to 13, where the aforementioned commit appeared.