Code Complete by Steve Mcconnell : Chapter 26

The author discusses about debugging in this chapter. The author provides a study to show the difference in time it takes for best and worst programmers to debug a program and the errors that get introduced while correcting the existing errors and the difference is huge.

The author then provides a list of things that a programmer can learn while debugging or fixing an error. The author also provides a list of ineffective approaches while debugging an error.

The author then provides a scientific method of debugging with following steps:

1. Gather data through repeatable experiments/Stabilize the error
   
2. Form a hypothesis that accounts for as much of the relevant data as possible/Locate the source of the error
   
3. Design an experiment to prove or disprove the hypothesis/Fix the error
   
4. Prove or disprove the hypothesis/Test the fix
   
5. Repeat as needed/Look for similar errors
   

The author then provides tips for finding errors:

• Use all the data available to make your hypothesis
• Refine the test cases that produce the error
• Reproduce the error several different ways
• Generate more data to generate more hypothesis
• Use the results of negative tests
• Brainstorm for possible hypothesis
• Narrow the suspicious region of the code
• Be suspicious of routines that have had errors before
• Check code that has changed recently
• Expand the suspicious region of the code
• Integrate incrementally
• Use brute force
• Set a maximum time for quick and dirty debugging
• Check for common errors
• Talk to someone else about the problem
• Take a break from the problem
  

The author then provides some tips on handling syntax errors.

The author then provides some tips on fixing errors:

• Understand the problem
• Understand the program
• Confirm the error diagnosis
• Relax
• Save the original source code
• Fix the problem not the symptom
• Make one change at a time
• Check your fix
• Look for similar errors

The author then provides a list of tools for debugging:

• Source code comparator
• Execution profiler
• Debugger