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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: 9 rules found
obsolete
    Impact
      Clean code attribute
        1. Digraphs should not be used

           Code Smell
        2. Trigraphs should not be used

           Code Smell
        3. GNU extensions should not be used

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

           Code Smell
        5. Obsolete POSIX functions should not be used

           Code Smell
        6. Code annotated as deprecated should not be used

           Code Smell
        7. Deprecated K&R syntax should not be used for function definition

           Code Smell
        8. Deprecated code should be removed

           Code Smell
        9. Deprecated attributes should include explanations

           Code Smell

        Trigraphs should not be used

        intentionality - clear
        maintainability
        Code Smell
        • based-on-misra
        • obsolete
        • cert
        • suspicious

        Why is this an issue?

        More Info

        Trigraphs are denoted by a sequence of 2 question marks followed by a specified third character (e.g. ??- represents a '~' (tilde) character and ??) represents a ']'). They can cause accidental confusion with other uses of two question marks.

        Noncompliant code example

        static const char str[] = "(Date should be in the form ??-??-??)"; // Noncompliant. Evaluates to "(Date should be in the form ~~]"
        

        Compliant solution

        static const char str[] = "(Date should be in the form ?" "?-?" "?-?" ?)";  // adjacent string literals concatenated at compile time
        static const char str2[] = "(Date should be in the form ?-?-?)"; // problem avoided by eliminating 2nd '?' in each sequence
        static const char str3[] = "(Date should be in the form ? ?-? ?-? ?)"; // problem avoided by spacing '?'s out
        
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          Developer Edition
          Available Since
          9.1

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