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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: 16 rules found
unused
    Impact
      Clean code attribute
        1. Non-empty statements should change control flow or have at least one side-effect

           Bug
        2. Unused type declarations should be removed

           Code Smell
        3. Functions that are not used in a project should be removed

           Code Smell
        4. Forward declarations should not be redundant

           Code Smell
        5. Declarations should not be empty

           Code Smell
        6. Conditionally executed code should be reachable

           Bug
        7. Values should not be uselessly incremented

           Bug
        8. Related "if/else if" statements should not have the same condition

           Bug
        9. Unused assignments should be removed

           Code Smell
        10. All code should be reachable

           Bug
        11. Unused local variables should be removed

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

           Code Smell
        13. Unused function parameters should be removed

           Code Smell
        14. Unused functions and methods should be removed

           Code Smell
        15. Empty statements should be removed

           Code Smell
        16. Unused labels should be removed

           Code Smell

        Unused function parameters should be removed

        intentionality - clear
        maintainability
        Code Smell
        • based-on-misra
        • cert
        • unused

        Why is this an issue?

        How can I fix it?

        More Info

        A typical code smell known as unused function parameters refers to parameters declared in a function but not used anywhere within the function’s body. While this might seem harmless at first glance, it can lead to confusion and potential errors in your code. Disregarding the values passed to such parameters, the function’s behavior will be the same, but the programmer’s intention won’t be clearly expressed anymore. Therefore, removing function parameters that are not being utilized is considered best practice.

        Exceptions

        There are some cases when you want to have an unused parameter (usually because the function has to conform to a fixed prototype, or because it is virtual, or it will be called from a template). In this case, and if the parameter is never used, an accepted practice is to leave it unnamed. If it is only sometimes used (for instance, depending on conditional compilation), you may, since C++17, use the [[maybe_unused]] attribute to be explicit about it.

        void f([[maybe_unused]] int i) {
          assert(i < 42); // In optimized mode, this assert will be removed, and "i" will be unused
        }
        

        In case of Objective-C, it is acceptable to have unused parameters if the method is supposed to be overridden. Additionally, since Objective-C blocks don’t allow unnamed parameters while they are typically used as callbacks, it is acceptable to have unused parameters in blocks.

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