-alt/base_as_notnull2_alt1.nit:30,12--25: Warning: expression is already not null, since it is a `Object`.
-alt/base_as_notnull2_alt1.nit:50,12--25: Warning: expression is already not null, since it is a `F: Object`.
+alt/base_as_notnull2_alt1.nit:30,12: Warning: expression is not null, since it is a `Object`.
+alt/base_as_notnull2_alt1.nit:50,12: Warning: expression is not null, since it is a `F: Object`.