strong memory leak in plpgsql from handled rollback and lazy cast

Hi

When I tested some hypothesis I wrote buggy code. It was surprise how fast I lost all free memory

do $$                  
begin
  for i in 1..3000000
  loop
    begin
      -- do some error
      if i then end if;
    exception when others then
      -- do nothing
    end;
  end loop;
end;
$$;

problem is somewhere in implicit casting inside IF statement. When I use explicit casting -

  IF i::boolean THEN

then there is not memory leak.

Regards

Pavel