GRANT '\0foo' TO bar;

10.0/sql/sql_acl.cc:5967: bool mysql_grant_role(THD*, List<st_lex_user>&, bool): Assertion `granted_role->is_role()' failed.
150813 14:08:45 [ERROR] mysqld got signal 6 ;

#6  0x00007f37e9cd0311 in *__GI___assert_fail (assertion=0xef990e "granted_role->is_role()", file=<optimized out>, line=5967, function=0xefc000 "bool mysql_grant_role(THD*, List<st_lex_user>&, bool)") at assert.c:81
#7  0x0000000000603fe9 in mysql_grant_role (thd=0x7f37e53d4070, list=..., revoke=false) at 10.0/sql/sql_acl.cc:5967
#8  0x0000000000682dcb in mysql_execute_command (thd=0x7f37e53d4070) at 10.0/sql/sql_parse.cc:4243
#9  0x0000000000688a5e in mysql_parse (thd=0x7f37e53d4070, rawbuf=0x7f37e3ff8088 "GRANT '", length=19, parser_state=0x7f37e33b4600) at 10.0/sql/sql_parse.cc:6531
#10 0x000000000067b43f in dispatch_command (command=COM_QUERY, thd=0x7f37e53d4070, packet=0x7f37e53ca071 "GRANT '", packet_length=20) at 10.0/sql/sql_parse.cc:1308
#11 0x000000000067a725 in do_command (thd=0x7f37e53d4070) at 10.0/sql/sql_parse.cc:999
#12 0x0000000000798c86 in do_handle_one_connection (thd_arg=0x7f37e53d4070) at 10.0/sql/sql_connect.cc:1378
#13 0x00000000007989e5 in handle_one_connection (arg=0x7f37e53d4070) at 10.0/sql/sql_connect.cc:1293
#14 0x0000000000cdb22b in pfs_spawn_thread (arg=0x7f37e3dda5f0) at 10.0/storage/perfschema/pfs.cc:1860
#15 0x00007f37ebacab50 in start_thread (arg=<optimized out>) at pthread_create.c:304
#16 0x00007f37e9d8095d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112