memory leak in postgresql

Hello

I found a following issue (tested on PostgreSQL 9.2)

CREATE OR REPLACE FUNCTION public.setfield(a anyelement, text, text)
RETURNS anyelement
LANGUAGE plpgsql
AS $function$
begin
  create temp table aux as select $1.*;
  execute 'update aux set ' || quote_ident($2) || ' = ' || quote_literal($3);
  select into $1 * from aux;
  drop table aux;
  return $1;
end;
$function$

create type mypoint as (a int, b int);

create table omega(p mypoint);

insert into omega select mypoint '(10,20)' from generate_series(1,100000);

update omega set p = setfield(p, 'a', '20');

WARNING:  out of shared memory
CONTEXT:  SQL statement "create temp table aux as select $1.*"
PL/pgSQL function "setfield" line 3 at SQL statement
ERROR:  out of shared memory
HINT:  You might need to increase max_locks_per_transaction.
CONTEXT:  SQL statement "create temp table aux as select $1.*"
PL/pgSQL function "setfield" line 3 at SQL statement

Regards

Pavel Stehule