Hi, just one question: I have a simple plugin (a minimal storage engine) that does not load. When I try to load it I get this error-message: MariaDB [(none)]> install plugin dummy soname 'ha_dummy'; ERROR 1126 (HY000): Can't open shared library '/home/august/MariaDB/pgm/lib/plugin/ha_dummy.so' (errno: 2 undefined symbol: _ZN9ha_myisam5cloneEPKcP11st_mem_root) Can you please give me a tip. Thanks. Environment is MariaDB 10.0.4. The same code works without any problems in MySQL (5.5.8 - just for a test). The code is a minimal engine that just does nothing, I want to use it as a template for further work. this is the code in the form that it is working (the relevant parts): in the header-file: class ha_dummy: public handler in the code: ha_dummy::ha_dummy(handlerton *hton, TABLE_SHARE *table_arg) :handler(hton, table_arg) now I change this by modifying the inheritance-order: in the header file: added: #include "../myisam/ha_myisam.h" #include "../myisam/myisamdef.h" modified: class ha_dummy: public ha_myisam in the code: /* Constructor */ ha_dummy::ha_dummy(handlerton *hton, TABLE_SHARE *table_arg) :ha_myisam(hton, table_arg) It compiles but I cannot load it. What's the problem with st_mem_root? Thanks AugustQ PS: as written before: both versions work with MySQL.