SonarSource Rules
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C

C static code analysis

Unique rules to find Bugs, Vulnerabilities, Security Hotspots, and Code Smells in your C code

  • All rules 315
  • Vulnerability13
  • Bug76
  • Security Hotspot19
  • Code Smell207

  • Quick Fix 19
Filtered: 22 rules found
confusing
    Impact
      Clean code attribute
        1. #include directives in a file should only be preceded by other preprocessor directives or comments

           Code Smell
        2. Loops should not have more than one "break" or "goto" statement

           Code Smell
        3. Switch labels should not be nested inside non-switch blocks

           Code Smell
        4. Appropriate char types should be used for character and integer values

           Code Smell
        5. The first element of an array should not be accessed implicitly

           Code Smell
        6. Multicharacter literals should not be used

           Code Smell
        7. GNU attributes should be used correctly

           Code Smell
        8. Functions which do not return should be declared as "noreturn"

           Code Smell
        9. Functions with "noreturn" attribute should not return

           Bug
        10. "else" statements should be clearly matched with an "if"

           Code Smell
        11. A conditionally executed single line should be denoted by indentation

           Code Smell
        12. Macros should not be redefined

           Code Smell
        13. "#include_next" should not be used

           Code Smell
        14. String literals should not be concatenated implicitly

           Code Smell
        15. Types and variables should be declared in separate statements

           Code Smell
        16. Format strings should be used correctly

           Code Smell
        17. Conditional operators should not be nested

           Code Smell
        18. Increment should not be used to set boolean variables to 'true'

           Code Smell
        19. Loops with at most one iteration should be refactored

           Bug
        20. Deprecated K&R syntax should not be used for function definition

           Code Smell
        21. Redundant pairs of parentheses should be removed

           Code Smell
        22. "/*" and "//" should not be used within comments

           Code Smell

        A conditionally executed single line should be denoted by indentation

        consistency - formatted
        maintainability
        Code Smell
        • confusing
        • suspicious

        Why is this an issue?

        When the line immediately after a conditional has neither curly braces nor indentation, the intent of the code is unclear and perhaps not what is executed. Additionally, such code is confusing to maintainers.

        if (condition)  // Noncompliant
        doTheThing();
        doTheOtherThing(); // Was the intent to call this function unconditionally?
        

        It becomes even more confusing and bug-prone if lines get commented out.

        if (condition)  // Noncompliant
        //  doTheThing();
        doTheOtherThing(); // Was the intent to call this function conditionally?
        

        Indentation alone or together with curly braces makes the intent clear.

        if (condition)
          doTheThing();
        doTheOtherThing(); // Clear intent to call this function unconditionally
        
        // or
        
        if (condition) {
          doTheThing();
        }
        doTheOtherThing(); // Clear intent to call this function unconditionally
        

        This rule raises an issue if the line controlled by a conditional has the same indentation as the conditional and is not enclosed in curly braces.

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          Available Since
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