Debugging is the process of finding bugs i.e. error in software or application and fixings them. Any software program or product which is being developed undergoes through various steps – testing, troubleshooting, maintenance in a different environment. These software programs or product contains some error or bug. These bugs need to be removed from the software to developed bug-free software. Debugging is nothing but a process that many software testers used to find those bugs and fix them. Debugging refers to finding bugs, analyzing, and fixings them. This process takes place when the software fails due to some errors or software performs an unwanted thing. Debugging looks simple but it is a complex task as there is a need to fix all errors at every stage of debugging.
Importance of debugging?
Debugging is an important part of determining why an operating system, application or program is misbehaving. Even if developers use the same coding standard, it's more than likely that a new software program will still have bugs. In many cases, the process of debugging a new software program can take more time than it took to write the program. Invariably, the bugs in software components that get the most use are found and fixed first.
Debugging Approaches:
The following are a number of approaches popularly adopted by programmers for debugging.
Brute Force Method: This is the foremost common technique of debugging however is that the least economical method. during this approach, the program is loaded with print statements to print the intermediate values with the hope that a number of the written values can facilitate to spot the statement in error. This approach becomes a lot of systematic with the utilisation of a symbolic program (also known as a source code debugger), as a result of values of various variables will be simply checked and breakpoints and watch-points can be easily set to check the values of variables effortlessly.
Backtracking: This is additionally a reasonably common approach. during this approach, starting from the statement at which an error symptom has been discovered, the source code is derived backward till the error is discovered. sadly, because the variety of supply lines to be derived back will increase, the quantity of potential backward methods will increase and should become unimaginably large so limiting the utilisation of this approach.
Cause Elimination Method: In this approach, a listing of causes that may presumably have contributed to the error symptom is developed and tests are conducted to eliminate every error. A connected technique of identification of the error from the error symptom is that the package fault tree analysis.
Program Slicing: This technique is analogous to backtracking. Here the search house is reduced by process slices. A slice of a program for a specific variable at a particular statement is that the set of supply lines preceding this statement which will influence the worth of that variable
Debugging Tools:
Debugging tool is a computer program that is used to test and debug other programs. A lot of public domain software like gdb and dbx are available for debugging. They offer console-based command line interfaces. Examples of automated debugging tools include code based tracers, profilers, interpreters, etc.
Some of the widely used debuggers are:
GDB (the GNU debugger)
LLDB
Radare2
Microsoft visual studio debugger
Valgrind
WinDBg
Firefox JavaScript debugger
Eclipse debugger
Arm DTT (Allinea DDT)
WDW (OpenWatcom debugger)
Process of Debugging
Below is the list of stages involved in the process of debugging:
1. Identify Error
Identifying errors at an early stage can save a lot of time. If we make a mistake in identifying an error, it leads to a lot of time wastage. Error or bugs occur at a customer site is hard to find. Identifying the right error is import to save time and avoid errors at the user site.
2. Identify the Error Location
After identifying an error, we need to identify the exact location in the code where an error occurs. Identifying an exact location that leads error can help to fix the problem faster.
3. Analyze Error
In this stage, you have to use an appropriate approach to analyze the error. This will help you to understand the problem. This stage is very critical as solving one error may lead to another error.
4. Prove the Analysis
Once the identified error has been analyzed, you have to focus on other errors of the software. This process involves test automation where you need to write the test cases through the test framework.
5. Cover Lateral Damage
In this stage, you have to do unit testing of all the code where you make the changes. If all test cases pass the test, then you can move to the next stage or else you have to resolve the test case that doesn’t pass the test.
6. Fix and validate
This is the final stage of the debugging process, where you need to fix all the bugs and test all test script.
Debugging Strategies
Below are the different strategies are as follows:
1. Learning Strategy
Before finding a bug in the software or product it is very important to learn that software or product very carefully. Because without any knowledge you cannot find errors. If you know the system very well and you know how it works then only you can find bugs in that software.
2. Experience
Previous experience can help you to find similar types of bugs and also the solution for resolving bugs. It depends upon the individual expert’s experience that how could he/she finds the bus quickly.
3. Forward Analysis
forward analysis of programs involves tracking program forward using print statements or breakpoints at different points. It is more concerned with the location where the wrong outputs are obtained.
4. Backward Analysis
Backward analysis of the program involves the tracking program backward from the location where errors occur to identify the region of the faulty code.
Debugging Advantages:
It supports the developer in minimizing the data.
If the perform the debugging, we can report the error condition directly.
During the debugging process, the developer can avoid complex one-use testing code that helps the developer save time and energy.
Debugging delivers maximum useful information of data structures and allows its informal understanding.
Debugging limitations
Watch expression: Agents are not supported (for instance “agent my_function” is not supported”).
You cannot yet create an instance of SPECIAL.
The debugger is not very helpful when the execution is stopped inside an invariant.
Debugging vs Testing
Testing | Debugging |
It is the implementation of the software with the intent of identifying the defects | The process of fixing and resolving the defects is known as debugging. |
Testing can be performed either manually or with the help of some automation tools. | The debugging process cannot be automated. |
Programming knowledge is not required to perform the testing process. | Without having an understanding of the programming language, we cannot proceed with the debugging process. |
Software Testing includes two or more activities such as validation and verification of the software. | Debugging tries to match indication with cause, hence leading to the error correction. |
It is built on different testing levels such as Unit Testing, Integration Testing, System Testing, etc. | It is built on different kinds of bugs because there is no such level of debugging is possible. |
Software testing contains various type of testing methods, which are as follow:
| Debugging involves a various type of approaches, which are as follows:
|
We can plan, design, and implement the testing process. | As compared to the testing process, the debugging process cannot be forced. |
Software testing is the presentation of defects. | It is a logical procedure. |
A group of test engineers executes testing, and sometimes it can be performed by the developers. | Debugging is done by the developer or the programmer. |
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