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
 
Tags
    Impact
      Clean code attribute
        1. Pointer and reference parameters should be "const" if the corresponding object is not modified

           Code Smell
        2. Non-standard characters should not occur in header file names in "#include" directives

           Bug
        3. Functions should not be declared at block scope

           Code Smell
        4. Literal suffix "L" for long integers shall be upper case

           Code Smell
        5. Digraphs should not be used

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

           Code Smell
        7. A single L in a literal suffix should only be used for long values

           Code Smell
        8. Loop variables should be declared in the minimal possible scope

           Code Smell
        9. Pointer and reference local variables should be "const" if the corresponding object is not modified

           Code Smell
        10. "sizeof" should not be called on pointers

           Bug
        11. Control characters should not be used in literals

           Code Smell
        12. Parameters should be passed in the correct order

           Code Smell
        13. Redundant casts should not be used

           Code Smell
        14. Multiple variables should not be declared on the same line

           Code Smell
        15. Unused local variables should be removed

           Code Smell
        16. Octal values should not be used

           Code Smell
        17. A "while" loop should be used instead of a "for" loop

           Code Smell
        18. Sections of code should not be commented out

           Code Smell
        19. Redundant pairs of parentheses should be removed

           Code Smell

        Redundant pairs of parentheses should be removed

        intentionality - clear
        maintainability
        Code Smell
        Quick FixIDE quick fixes available with SonarLint
        • confusing

        Why is this an issue?

        Parentheses can disambiguate the order of operations in complex expressions and make the code easier to understand.

        a = (b * c) + (d * e); // Compliant: the intent is clear.
        

        Redundant parentheses are parenthesis that do not change the behavior of the code, and do not clarify the intent. They can mislead and complexify the code. They should be removed.

        Noncompliant code example

        int x = ((y / 2 + 1)); // Noncompliant
        
        if (a && ((x + y > 0))) { // Noncompliant
          return ((x + 1)); // Noncompliant
        }
        

        Compliant solution

        int x = (y / 2 + 1);
        
        if (a && (x + y > 0)) {
          return (x + 1);
        }
        

        Exceptions

        Assignments inside conditions are often the result of a mistake. S1121 flags this potential bug.

        if (x = 7) { // Noncompliant: Did the author mean "x == 7"?
          // ...
        }
        

        Adding a pair of parentheses to clearly state the intent is standard practice and is accepted by this rule.

        if ((x = 7)) { // Compliant
          // ...
        }
        
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          Available Since
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