A Folklore Confirmation on the Removal of Dead Code

In this folklore-confirmation short paper, we present the results of a study on the removal of dead code. We aim to gather evidence on the impact of dead-method removal on the internal structure of source code and the usage of resources such as compilation time and space to store executable code. To that end, we studied 23 open-source Java desktop applications hosted on GitHub. We cleaned up each of these applications from its dead methods to obtain two versions: one with dead methods (i.e., original version) and another one without them (i.e., cleaned version). For each of these applications, we compared its versions (original and cleaned) to determine whether, and to what extent, the removal of dead methods affects the internal structure of source code and the usage of resources. We observed that, after removing dead methods, the internal structure of source code significantly improves, while the time to compile source code significantly diminishes as well as the space to store executable code.