Top 11 Types Of Errors In C Programming When Executing Code

Hello guys, welcome back to our blog. Here in this article, we will discuss the top 11 types of errors in C programming when executing code, we will be also providing the proper solution with examples and fixing the faults at various stages.

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Types Of Errors In C Programming

Errors are problems or defects in the program that lead to strange behavior. These errors can be made even by expert engineers. Debugging is the process of eradicating flaws, which are sometimes referred to as faults or bugs in the programming. Error is a user-performed illegal action that causes the application to operate abnormally.

Programming mistakes frequently go unnoticed until the program is compiled or run. A few of the errors prevent the program from being built or run. Therefore, errors should be fixed before compilation and execution. Even skilled and seasoned programmers make mistakes. Errors are defects or faults in the code that cause our software to act unpredictably.

Programming errors are frequently referred to as bugs, and the procedure used to fix them is known as debugging or debugging. Each error must be found and reported to the user, and then a recovery strategy must be developed and put into action to deal with the error. The program’s processing speed shouldn’t be slow throughout this entire process.

Roles of the error handler:

Detection of error
Reporting the error
Recovery of error

The empty entries in the symbol table are considered errors. The parser should be able to identify and report program errors. The parser can handle any errors that come up while still processing the rest of the input. Even though the parser is primarily in charge of checking for errors, mistakes can still happen during the compilation process.

The fixing of faults in the compiler’s various stages.

01. Recovery in panic mode :

This is the simplest method of mistake recovery, and it also stops the parser from creating endless loops while doing so. Until one of the designated (such as end, semicolon) set of synchronization tokens (which are often the statement or expression terminators) is located, the parser discards each input symbol one at a time. When there aren’t often numerous errors in a single statement, this is sufficient.

Ex: Consider the expression which contains the error – (2 + + 5) + 7.

Panic mode: Go ahead and move on to the following integer.

Bison: To specify how much input to skip, use the specific terminal error.

A parser ignores the remainder of the statement when it meets an error anywhere in the statement by not processing input from incorrect input to a delimiter, such as a semicolon. The parser is kept from creating endless loops thanks to this method of error recovery, which is also the simplest.

02. Recovery at the phase level :

The parser makes a local fix to the remaining input when an error is found. To continue parsing the rest of the statement after running across an error, a parser fixes the problem on the remaining input. You can fix the mistake by removing superfluous semicolons, switching out commas for semicolons, or adding any that are missing.

Maximum caution should be used throughout the adjustment to avoid entering an infinite loop. Any prefix that is discovered in the remaining input is replaced with a string each time. The parser can carry on with its execution in this manner.

03. Production of error:

If the user is aware of frequent grammatical errors as well as errors that result in erroneous constructs, they can incorporate the error production approach. When this method is applied, parsing can proceed even when error messages are produced. Write 5x instead of 5*x, for instance.

The compiler designers are aware of a few typical mistakes that could happen in the code. Additionally, the designers have the option of using augmented grammar to produce productions that produce incorrect constructions when these mistakes are found.

04. Correction at the global level :

The parser examines the entire program and seeks out the closest match that is error-free to recover from incorrect input. The most accurate match is one with the fewest token insertions, deletions, and alterations. Due to its high time and spatial complexity, this method is not viable.

The parser takes the program under consideration as a whole, tries to determine what it is intended to perform, and looks for the program’s closest match that is free of errors. Upon receiving an incorrect input (statement), X, it builds a parse tree for the nearest error-free sentence, Y.

05. Mode of the statement:

When a parser runs into a problem, it tries to fix it such that the remaining inputs to the statement will allow it to continue parsing—for instance, replacing a comma with a semicolon or adding a missing semicolon. Here, parser designers must exercise caution because a single error could result in an endless cycle.

Debugging

In computer programming and engineering, debugging is a multi-step process that entails locating a problem, tracking down the source of the problem, and either fixing the problem directly or finding a workaround. Testing the fix or workaround to make sure it functions is the last stage in the debugging process.

When a developer can find and reproduce a code error in a computer program, the debugging process in software development gets started. The software testing process, as well as the full software development lifecycle, includes debugging.

The debugging process in hardware development often looks for hardware components that are improperly installed or configured. A JTAG connection test, for instance, could be used by an engineer to debug connections on an integrated circuit.

Debugging typically begins as soon as code is created and proceeds in phases when code is coupled with other programming units to develop a software product. Using techniques like unit tests, code reviews, and pair programming can make troubleshooting a considerable application with tens of thousands of lines of code easier.

Examining the code’s logging and using a standalone debugger tool or the debug mode of an integrated development environment might help find issues (IDE). If the developer is familiar with normal error messages at this point, it may be useful.

However, even the cleanest code might be difficult to debug if developers don’t sufficiently remark on their code when they write it. Sometimes the line of code itself is evident, but the module that exposes the issue is not. Unit tests, which allow the programmer to execute a particular function with a specified set of inputs, can be useful in this situation. Examples include JUnit and xUnit.

The accepted procedure is to create a “breakpoint” and run the program up until it, at which point execution is stopped. The debugger feature of an IDE typically gives programmers the ability to view memory and see variables, run the program to the next breakpoint, execute just the next line of code, and, in some cases, change the value of variables or even the contents of the line of code that is about to be executed.

Determining the cause of an operating system, application, or program’s improper behavior requires extensive debugging. Even if programmers adhere to the same coding standards, it’s still very possible that a new piece of software may contain defects. Debugging a new software program can frequently take longer than the time it took to write the program. The software flaws that are used the most are always discovered and corrected earliest.

The processes of debugging and testing work in tandem. Testing is done to find out what happens when a program’s source code is incorrect. Debugging is used to identify and correct errors. The testing procedure just displays the effects of the coding fault on the application; it does not assist the developer in identifying the mistake in the code.

Debugging assists the developer in identifying the error’s root cause so that it can be corrected after it has been identified.

Debugging can benefit from the use of source code analyzers, which include security, frequent code faults, and complexity analyzers. A complexity analyzer can identify modules that are overly complex and difficult to test. The following are some other debugging techniques:

1. Static analysis is when a developer looks at the code but doesn’t run the application.
2. Print debugging (also known as tracing): the developer keeps an eye on the flow and records live or recorded print statements.
3. Remote debugging, in which the debugger used by the developer runs on a different machine than the software being examined.
4. Post-mortem debugging, where the developer only stops to examine the code after a program encounters a fatal error.

A debugger is a software tool that can aid in the development of software by spotting code problems at different stages of the creation of an operating system or an application. Some debuggers examine a test run to determine which lines of code were skipped.

Simulators offered by other debugging tools enable programmers to simulate how an app will seem and function on a certain operating system or computing device.

Numerous open-source debugging tools and scripting languages cannot be run in an IDE, necessitating a more labor-intensive debugging process.

For instance, USB Debugging enables communication between an Android device and a computer running the Android SDK. In this case, the developer may debug a program by writing values to a log, writing numerous print statements to track code execution, or implementing wait instructions that are hard-coded to simulate breakpoints by waiting for keyboard input at certain intervals.

Types Of Errors In C Programming

01. Runtime error

Runtime errors are errors that happen while a program is running after it has been successfully compiled. The following techniques can be used to determine the cause of a runtime error:

Method 1: When a negative index is assigned to an array’s index, an invalid memory access runtime error results.

Method 2: Arrays or vectors may occasionally exceed their bounds, resulting in runtime errors. Index out of bounds is the cause of this issue, as explained. It can be solved by keeping the array/vector size within the allowed range.

Method 3: Some foolish errors made while developing in a rush can result in runtime errors.

Run-time errors are errors that arise after a program has successfully been compiled. The most prevalent run-time errors are numbers that are divisible by zero, out-of-bounds array and string indexes, and others. These faults shouldn’t be extremely challenging to find during compilation.

Runtime errors are errors that happen while a program is being run. Runtime errors only happen while the program is being executed, as opposed to compilation errors, which can happen at any moment throughout the compilation of a program. Runtime errors signify program faults or problems that the program’s creators had anticipated but were unable to fix. For instance, runtime errors sometimes result from insufficient memory.

Runtime errors typically manifest themselves as a message box with an associated error code and description. It happens rather frequently for the computer to start acting visibly slow before a runtime problem shows up.

Runtime errors are produced by software when a problem arises and is impossible to be fixed. Here, the issue is caused by that particular piece of software rather than the OS. The software performs self-diagnosis through the use of a trap, a self-evaluation mechanism, and determines that it cannot continue, resulting in a runtime fault. The associated software is typically quit or frozen when the runtime error is shown and closed. The OS is occasionally rebooted.

Runtime errors can have several causes. Here are a few of them:

Conflicts between the programs to terminate and keep residents (TSR)
Applications running into problems
Memory problems
programming errors
Additional software issues
outdated or broken hardware
applications that are harmful or dangerous, such as computer viruses or hardware

02. Semantic error

Semantic errors are errors that happen when the compiler is unable to comprehend the written code. Despite being syntactically correct, a semantic error will be produced if the compiler cannot understand the code. It is analogous to using the incorrect word in the incorrect context when speaking English. A semantic mistake will result, for instance, from adding a string to an integer.

Semantic mistakes are distinct from syntax errors since the former indicate that a program’s structure is flawed without taking into account its meaning. Semantic mistakes, on the other hand, represent a program’s improper implementation when the program’s intent is taken into account.

Use of uninitialized variables, type compatibility, and array index out of limits are the most frequent semantic errors.

03. Logic error

After a program has been compiled and executed, we occasionally may not obtain the results we were hoping for. Although the code appears to be error-free, the result that is produced is not what was anticipated. Logical errors are the name for this category of faults.

Logical errors are ones in which we believe our code to be accurate, where it compiles without a problem and displays no errors while it is running, but where the result is not what we anticipated. NASA lost a spacecraft in 1999 as a result of a logical mistake.

This occurred as a result of several calculation errors between the English and American Units. The software was designed to operate with one system, but it was utilized with another.

04. Linker error

The object files produced by the compiler are combined into a single executable file by a program called a linker. When the executable file of the code cannot be generated even though the code is correctly built, linker faults are present.

When an additional object file is unable to link with the primary object file, this error is produced. A linked error can occur if we import the wrong header file, have an erroneous function declaration, etc.

05. Syntax error

“Syntax errors” are considered to arise when the conventions for writing C syntax are broken. Before the code is built, this compiler error indicates that it has to be corrected. The term “compile-time errors” refers to faults that are discovered by the compiler.

Syntax errors are mistakes that happen when you don’t follow the guidelines for writing C/C++ syntax. This compiler problem requires a correction before the code can be compiled. These are all compile-time faults since the compiler can identify them all.

The most typical syntactic mistakes are:

Absence of a parenthesis
displaying a variable’s value without declaring it
Semicolon missing, as in:

a C program to show

#include<stdio.h>
int main(void){
// while() cannot contain “.” as an argument.
while(.)
{
printf(“hello”);
}
return 0;
}

Error: If there was an unexpected phrase before the token “.,” (.)

The while loop’s syntax in the provided example is wrong. This results in a syntax mistake. When a C++ authoring style or syntactic guideline is broken, this type of error occurs. Before compilation, the compiler typically indicates this kind of mistake. These are sometimes referred to as compile-time errors.

Ex:

#include<stdio.h>
main() {
printf(“Hello World”)
}

Output: Error] expected ‘;’ before ‘}’ token

As they occurred during compilation, syntax mistakes are also referred to as compilation errors. Alternatively, we may say that syntax errors are thrown by compilers.

These issues typically result from typing errors or from failing to adhere to the syntax of the stated programming language. Because they are unfamiliar with the language, beginners frequently make these errors. These mistakes are simple to debug or fix.

06. Missing or mismatched parentheses in the syntax

A common type of punctuation for many programming languages is the parenthesis. It facilitates the execution of strings, functions, and code organization. It can be simple for a beginner to forget how many parentheses have been used or if they are matched up correctly when developing code. The code won’t be compiled if one end of the parenthesis is missing. Additionally, if the parenthesis is mismatched, the code might not carry out the function as intended.

How to Correct It: Verify that the parentheses are paired up correctly if a syntax mistake occurs. Check to see if the code can be compiled after typing the correction if one end is missing or lined up improperly. It also helps to keep the code as organized as you can. A coder can keep track of parenthesis considerably more simply and avoid mistakes if they are arranged in a logical pattern or are obvious to see.

07. Undeclared or misspelled variables in the syntax

Variables store the value of data, text, or numerical values. Variables give coding flexibility and enable proficient usage of programming languages by coders. A variable must be declared early in the code for it to function. Unskilled programmers could mistakenly fail to declare a variable or spell it incorrectly somewhere in the code.

08. Unmatched/Missing Quotes Syntax Error

Strings can contain quotations to display a statement. The statement can be displayed inside of parentheses using either double quotes (“) or single quotes (‘), but not both at the same time. Some programmers could use the wrong quotations or neglect to add the end of a quote, which will result in an error.

How to Correct It Look to check if a quote is missing. Similar to how you would verify the parenthesis, match up the quotes. If the quotations don’t line up, fix the mistake and make sure the code can still run.

09. Incorrect or incomplete return statement syntax

Programs are instructed to go back to a previous activity using return statements. The code may contain a return statement or return value. One of the previously stated problems, such as an undeclared variable, missing parenthesis, or a misspelled word, can occasionally be found in a return statement.

How to Correct It, Check the return statement for any spelling or punctuation mistakes.

10. The semicolon is missing in the syntax

Because they signify a pause in a line of code, semicolons are crucial for many programming languages. In C and Java, semi-colons are most frequently employed. These programming languages may make this syntactic error more common. In a line of code, if there isn’t a semicolon, the statement goes on until there is one. If there is further punctuation or a statement, it will typically be detected as an error.

How to Correct It Check the statement’s conclusion to determine if the semicolon is there. Get into the habit of adding a semi-colon when writing code the same way you would a period after a sentence.

Why Is Correcting Syntax Errors Important?

The code won’t be compiled, even if the syntax problem is minimal. To avoid not knowing whether a program is working, syntax problems must be rapidly fixed.

11. Minor category of errors

The other minor category of errors includes failing to adhere to accepted coding conventions, utilizing the incorrect function, Using the incorrect variable name in the incorrect location, and not initializing a variable when it is necessary to omit the verification of an error return.

This was about “Types Of Errors In C Programming“. I hope this article may help you all a lot. Thank you for reading.

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