1 alt/base_as_notnull2_alt2.nit:30,12: Warning: expression is not null, since it is a `Object`.
2 alt/base_as_notnull2_alt2.nit:50,12: Warning: expression is not null, since it is a `F: Object`.
3 Runtime error: Cast failed (alt/base_as_notnull2_alt2.nit:40)