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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
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  • Code Smell207

  • Quick Fix 19
Filtered: 17 rules found
bad-practice
    Impact
      Clean code attribute
        1. Pointer and reference parameters should be "const" if the corresponding object is not modified

           Code Smell
        2. Reserved identifiers should not be defined or declared

           Code Smell
        3. Only standard forms of the "defined" directive should be used

           Code Smell
        4. Function-like macros should not be used

           Code Smell
        5. Recursion should not be used

           Code Smell
        6. "continue" should not be used

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

           Bug
        8. Functions should be declared explicitly

           Code Smell
        9. Names of well-known C standard library macros and functions should not be used as identifiers

           Code Smell
        10. Macros should not be used as replacements for "typedef" and "using"

           Code Smell
        11. Size of bit fields should not exceed the size of their types

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

           Code Smell
        13. Argument of "printf" should be a format string

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

           Bug
        15. "if" statements should be preferred over "switch" when simpler

           Code Smell
        16. Track uses of "NOSONAR" comments

           Code Smell
        17. Deprecated attributes should include explanations

           Code Smell

        Only standard forms of the "defined" directive should be used

        consistency - conventional
        maintainability
        Code Smell
        • based-on-misra
        • bad-practice

        Why is this an issue?

        More Info

        The defined preprocessing directive is used in the context of #if and #elif expressions to see whether a given identifier has been defined as a macro. It returns a value of 0 (false) or 1 (true), and has two valid forms, defined IDENTIFIER and defined ( IDENTIFIER ). Since it is essentially a macro existence check, it cannot take expressions as arguments.

        Note that since

        #if defined AN_IDENTIFIER

        is equivalent to

        #ifdef AN_IDENTIFIER

        defined is most useful when there are multiple arguments to check, E.G.

        #if defined AAA || defined BBB

        Noncompliant code example

        #if defined ( X > Y ) // Noncompliant; expressions not allowed
        

        Compliant solution

        #if defined X && defined Y && X > Y
        
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