evaluator: fix out of bound array access
evaluator: fix out of bound array access

Fix https://scan7.coverity.com/reports.htm#v23575/p13316/fileInstanceId=8428808&defectInstanceId=2110135&mergedDefectId=1396765

AravisProject/aravis,AravisProject/aravis,AravisProject/aravis,AravisProject/aravis,AravisProject/aravis