A dynamic approach to detecting, eliminating and fixing memory leaks

Abstract

This paper presents a dynamic approach to detecting, eliminating and fixing memory leaks. With our approach, a program to be analyzed is instrumented before its execution. Dynamic symbolic execution is employed so as to expose memory leaks occurring in all execution paths. During the program execution, information about each allocated memory area is updated when corresponding statements are executed. Based on this information, a back-end leak checker records the changes of variables pointing to each memory area, detects memory leaks and deallocates leaked memory areas. After the program execution, a fixed program containing deallocation statements is generated. We have implemented our approach in a tool called DEF_LEAK based on Low Level Virtual Machine compiler infrastructure. Experiments show that DEF_LEAK can detect more leaks than the existing dynamic detection tools for programs with user inputs. Moreover, DEF_LEAK is more effective for helping programmers understand and fix memory leaks than other detection tools.