# Delta debugging

> Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Delta_debugging
> Markdown URL: https://mediated.wiki/source/Delta_debugging.md
> Source: https://en.wikipedia.org/wiki/Delta_debugging
> Source revision: 1272953202
> License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/)

{{Sources exist|date=January 2025}}

'''Delta debugging''' is a methodology to automate the [debugging](/source/debugging) of programs using a scientific approach of hypothesis-trial-result loop. This methodology was first developed by Andreas Zeller of the Saarland University in 1999.<ref>{{cite conference |last1=Zeller |first1=Andreas |book-title=Software Engineering — ESEC/FSE '99 |volume=1687 |pages=253–267 |title=Yesterday, my program worked. Today, it does not. Why?|date=1999 |publisher=Springer |doi=10.1007/3-540-48166-4_16 |series=Lecture Notes in Computer Science |isbn=978-3-540-66538-0}}</ref>

The delta debugging algorithm isolates failure causes automatically by systematically narrowing down failure-inducing circumstances until a minimal set remains. For example, if you can supply a test case that will produce the bug you are looking for, then you can feed that to the delta debugging algorithm, which will then trim lines of code that are not needed to reproduce the bug, until a 1-minimal program is found.

Delta debugging has been applied to isolate failure-inducing program input (e.g. an HTML page that makes a Web browser fail), failure-inducing user interaction (e.g. the keystrokes that make a program crash), or failure-inducing changes to the program code (e.g. after a failing regression test).

Software development tools inspired by delta debugging include the [bisect commands](/source/Bisection_(software_engineering)) of [revision control](/source/revision_control) systems (e.g., git-bisect, svn-bisect, hg-bisect, etc.), which, instead of working on the program's code, apply the delta debugging methodology on the code history by comparing various versions until the faulty change is found.

==See also==

* [Bisection (software engineering)](/source/Bisection_(software_engineering))
* [Program slicing](/source/Program_slicing)

==References==
<references />

==External links==
*[http://www.st.cs.uni-sb.de/dd/ Delta Debugging project]

Category:Debugging

---
Adapted from the Wikipedia article [Delta debugging](https://en.wikipedia.org/wiki/Delta_debugging) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Delta_debugging?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.