Time travel debugging or time traveling debugging is the process of stepping back in time through source code to understand what is happening during execution of a computer program. [1] Typically, debugging and debuggers, tools that assist a user with the process of debugging, allow users to pause the execution of running software and inspect the current state of the program. [2] Users can then step forward in time, stepping into or over statements and proceeding in a forward direction. [3] Interactive debuggers include the ability to modify code and step forward based on updated information. [4] Reverse debugging tools allow users to step backwards in time through the steps that resulted in reaching a particular point in the program. Time traveling debuggers provide these features and also allow users to interact with the program, changing the history if desired, and watch how the program responds. [5]
There are several characteristics that support the ability to move backwards as well as forwards in time.
Examples of debuggers with the ability to step backwards:
Language | Debuggers |
---|---|
C++ | rr for x86 Linux, Undo UDB for Linux [9] |
R | provDebugR [10] |
Python | PyTrace [11] |
JavaScript | Wallaby.js, [12] Meiosis Tracer [13] |
C# | RevDeBug |
Java | RevDeBug for C# and Java, [14] WhyLine for Java, [15] Undo UDB |
Elm | Elm Debugger, Elm Reactor [16] |
OCaml | ocamldebug |
Go | Undo UDB for Linux [17] |
Rust | Undo UDB for Linux [18] |
Windows Native | Microsoft Time Travel Debugging (TTD) Tool [19] for native Windows software (x86, x64, ARM, ARM64 [20] ), eShard esReven Full System Timeless Analysis for Windows [21] |
Linux Native | eShard esReven Full System Timeless Analysis for Linux [22] |
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