Memory was leaked when ALTER TABLE is attempted on a table
that contains corrupted indexes.
The memory leak was reported by AddressSanitizer for the test
innodb.innodb_corrupt_bit. The leak was introduced into
MariaDB Server 10.0.26, 10.1.15, 10.2.1 by the following:

commit c081c978
Merge: 1d21b221 a482e76e
Author: Sergei Golubchik <serg@mariadb.org>
Date:   Tue Jun 21 14:11:02 2016 +0200

   Merge branch '5.5' into bb-10.0