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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: 13 rules found
lock-in
    Impact
      Clean code attribute
        1. "<time.h>" should not be used

           Code Smell
        2. "<stdio.h>" should not be used in production code

           Code Smell
        3. "<signal.h>" should not be used

           Bug
        4. Preprocessor operators "#" and "##" should not be used

           Code Smell
        5. Bitwise operators should not be applied to signed operands

           Bug
        6. Bit fields should be declared with appropriate types

           Code Smell
        7. Multicharacter literals should not be used

           Code Smell
        8. Arguments evaluation order should not be relied on

           Bug
        9. "#include_next" should not be used

           Code Smell
        10. GNU extensions should not be used

           Code Smell
        11. The "sizeof" and "alignof" operator should not be used with operands of a "void" type

           Bug
        12. Keywords introduced in later specifications should not be used as identifiers

           Code Smell
        13. Control should not be transferred into a complex logic block using a "goto" or a "switch" statement

           Code Smell

        Multicharacter literals should not be used

        intentionality - complete
        maintainability
        Code Smell
        • lock-in
        • confusing

        Why is this an issue?

        Multicharacter literals have int type and have an implementation-defined value. This means they might be interpreted differently by different compilers. For example, they might lead to different behavior when compiled with GCC than when compiled with MSVC.

        Even if they work as you expect with a specific compiler, they will make your code less portable. They are also misleading as they look like strings, hence make your code less readable.

        Noncompliant code example

        void f(int i) {
          // ...
          if (i == 'abcd') { // Noncompliant
            // ...
          }
        }
        
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          on-premise CI
          Developer Edition
          Available Since
          9.1

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