fix valgrind in test 158
fix valgrind in test 158

deaktator/vowpal_wabbit,jon-morra-zefr/vowpal_wabbit,hal3/vowpal_wabbit,hal3/vowpal_wabbit,deaktator/vowpal_wabbit,hal3/vowpal_wabbit,hal3/vowpal_wabbit,deaktator/vowpal_wabbit,hal3/vowpal_wabbit,hal3/vowpal_wabbit,hal3/vowpal_wabbit,deaktator/vowpal_wabbit,hal3/vowpal_wabbit,deaktator/vowpal_wabbit,deaktator/vowpal_wabbit,hal3/vowpal_wabbit,deaktator/vowpal_wabbit,jon-morra-zefr/vowpal_wabbit,deaktator/vowpal_wabbit,jon-morra-zefr/vowpal_wabbit,deaktator/vowpal_wabbit,deaktator/vowpal_wabbit,hal3/vowpal_wabbit,jon-morra-zefr/vowpal_wabbit,jon-morra-zefr/vowpal_wabbit,jon-morra-zefr/vowpal_wabbit,jon-morra-zefr/vowpal_wabbit,jon-morra-zefr/vowpal_wabbit,deaktator/vowpal_wabbit,jon-morra-zefr/vowpal_wabbit,jon-morra-zefr/vowpal_wabbit,jon-morra-zefr/vowpal_wabbit,hal3/vowpal_wabbit