Improve error message management then an asserter is unknwon.
Improve error message management then an asserter is unknwon.

jubianchi/atoum,gpaton/atoum,agallou/atoum,vonglasow/atoum,mageekguy/atoum,tejerka/atoum,CedCannes/atoum,CedCannes/atoum,mikaelrandy/atoum,Tiross/atoum,Tiross/atoum,vonglasow/atoum,gpaton/atoum,mikaelrandy/atoum,tejerka/atoum,mageekguy/atoum,agallou/atoum,jubianchi/atoum,GuillaumeDievart/atoum,GuillaumeDievart/atoum