According to the Software Engineering Institute and the IEEE, every significant piece of software will initially contain defects, typically around two per 100 lines of code. These mistakes lead to programs and libraries that don’t perform as required, often causing a program to behave differently than it’s supposed to. Bug tracking, identification, and removal can consume a large amount of a programmer’s time during software development.
In this chapter, we look at software defects and consider some tools and techniques for tracking down specific instances of erroneous behavior. This isn’t the same as testing (the task of verifying the program’s operation in all possible conditions), although testing and debugging are, of course, related, and many bugs are discovered during the testing process.
Topics we cover include
- Types of errors
- General debugging techniques
- Debugging with GDB and other tools
- Memory use debugging
Types of Errors
A bug usually arises from one of a small number of causes, each of which suggests a specific method of detection and removal:
- Specification errors: If a program is incorrectly specified, it will inevitably fail to perform as required. Even the best programmer in the world can sometimes write the wrong program. Before you start programming (or designing), make sure that you know and understand clearly what your program needs to do. You can detect and remove many (if not all) specification errors by reviewing the requirements ...