Feature-Based Detection of Bugs in Clones

Clones bear the risk of incomplete bugfixes when the bug is fixed in one code fragment but at least one of its copies is not changed and remains faulty. Although we find incompletely fixed clones in almost every system, it is usually time consuming to manually locate these clones inside the results of an ordinary clone detection tool. In this paper, we describe in how far certain features of clones can be used to automatically identify incomplete bugfixes. The results are relevant for developers to locate incomplete bugfixes-that is, defects still existing in the system-and for us as clone researchers to quickly find examples that motivate the use of clone management.