Trying to get some variables.
Some pointers may be invalid and cause the dump to abort.
Query (7f7804004bd0): is an invalid pointer
Connection ID (thread ID): 2
The manual page at http://dev.mysql.com/doc/mysql/en/crashing.html
information that should help you find out what is causing the crash.
160311 10:06:19 mysqld_safe Number of processes running now: 0
160311 10:06:19 mysqld_safe mysqld restarted
160311 10:06:19 [Warning] Using unique option prefix key_buffer instead of key_buffer_size is deprecated and will be removed in a future release. Please use the full name instead.
160311 10:06:19 [Note] /usr/sbin/mysqld (mysqld 5.5.47-0ubuntu0.14.04.1) starting as process 30508 ...
160311 10:06:19 [Warning] Using unique option prefix myisam-recover instead of myisam-recover-options is deprecated and will be removed in a future release. Please use the full name instead.
160311 10:06:19 [Note] Plugin 'FEDERATED' is disabled.
160311 10:06:19 InnoDB: The InnoDB memory heap is disabled
160311 10:06:19 InnoDB: Mutexes and rw_locks use GCC atomic builtins
160311 10:06:19 InnoDB: Compressed tables use zlib 1.2.8
160311 10:06:19 InnoDB: Using Linux native AIO
160311 10:06:19 InnoDB: Initializing buffer pool, size = 128.0M
160311 10:06:19 InnoDB: Completed initialization of buffer pool
160311 10:06:19 InnoDB: highest supported file format is Barracuda.
160311 10:06:20 InnoDB: Waiting for the background threads to start