server"
Bug appears only on Windows platform. Freeing memory in 
TMP_TABLE_PARAM::cleanup() allocated by new Copy_fields[0] in 
setup_copy_fields() results in memory destruction. In test IF used instead 
of CONCAT because IF have more stable crash.



sql/sql_select.cc:
  Fix bug #9593 The combination of COUNT, DISTINCT and CONCAT seems to lock the server
mysql-test/t/count_distinct.test:
  test for bug #9593 The combination of COUNT, DISTINCT and CONCAT seems to lock the server
mysql-test/r/count_distinct.result:
  Test for bug #9593 The combination of COUNT, DISTINCT and CONCAT seems to lock the server