Just for the record, I can reproduce the problem with Perl 5.12.2 on Linux (Ubuntu) for all of the cases except the last three (i.e., in contrast to you, also for 'temp_keep_name' and 'buf').  With 5.10.1, however, I get the error only with case 'buf'.

(Destroying the tied handle before global destruction (as mentioned by ikegami) makes no difference.)