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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: 37 rules found
suspicious
    Impact
      Clean code attribute
        1. "offsetof" macro should not be used

           Code Smell
        2. "errno" should not be used

           Code Smell
        3. Function names should be used either as a call with a parameter list or with the "&" operator

           Code Smell
        4. "enum" values should not be used as operands to built-in operators other than [ ], =, ==, !=, unary &, and the relational operators <, <=, >, >=

           Code Smell
        5. "bool" expressions should not be used as operands to built-in operators other than =, &&, ||, !, ==, !=, unary &, and the conditional operator

           Code Smell
        6. A cast shall not remove any const or volatile qualification from the type of a pointer or reference

           Code Smell
        7. Trigraphs should not be used

           Code Smell
        8. "#pragma pack" should be used correctly

           Bug
        9. Only valid arguments should be passed to UNIX/POSIX functions

           Code Smell
        10. Only valid arguments should be passed to stream functions

           Code Smell
        11. "^" should not be confused with exponentiation

           Code Smell
        12. Size of variable length arrays should be greater than zero

           Code Smell
        13. "mktemp" family of functions templates should have at least six trailing "X"s

           Code Smell
        14. Unevaluated operands should not have side effects

           Code Smell
        15. Size argument of memory functions should be consistent

           Code Smell
        16. Return value of "nodiscard" functions should not be ignored

           Code Smell
        17. Implicit casts should not lower precision

           Code Smell
        18. Appropriate size arguments should be passed to "strncat" and "strlcpy"

           Code Smell
        19. User-defined types should not be passed as variadic arguments

           Bug
        20. Array values should not be replaced unconditionally

           Bug
        21. A conditionally executed single line should be denoted by indentation

           Code Smell
        22. Conditionals should start on new lines

           Code Smell
        23. "case" ranges should cover multiple values

           Code Smell
        24. "switch" statements should cover all cases

           Code Smell
        25. Redundant pointer operator sequences should be removed

           Code Smell
        26. Conditionally executed code should be reachable

           Bug
        27. Flexible array members should not be declared

           Code Smell
        28. Track parsing failures

           Code Smell
        29. Recursion should not be infinite

           Bug
        30. Two branches in a conditional structure should not have exactly the same implementation

           Code Smell
        31. Pre-defined macros should not be defined, redefined or undefined

           Code Smell
        32. Switch cases should end with an unconditional "break" statement

           Code Smell
        33. "switch" statements should not contain non-case labels

           Code Smell
        34. Methods should not be empty

           Code Smell
        35. Assignments should not be made from within conditions

           Code Smell
        36. Variables should not be shadowed

           Code Smell
        37. Nested blocks of code should not be left empty

           Code Smell

        "bool" expressions should not be used as operands to built-in operators other than =, &&, ||, !, ==, !=, unary &, and the conditional operator

        intentionality - complete
        maintainability
        Code Smell
        • based-on-misra
        • suspicious

        Why is this an issue?

        More Info

        The use of bool operands with other operators is unlikely to be meaningful (or intended). Best case it will be confusing to maintainers, worst case it will not have the intended effect. Either way, it is highly recommended to stick to boolean operators when dealing with bool operands.

        This rule allows the detection of such uses, which often occur because the logical operators (&&, || and !) can be easily confused with the bitwise operators (&, | and ~).

        Noncompliant code example

        bool b1 = true;
        bool b2 = false;
        int8_t s8a;
        if ( b1 & b2 ) // Noncompliant
        if ( ~b1 ) // Noncompliant
        if ( b1 < b2 ) // Noncompliant
        if ( b1 ^ b2 ) // Noncompliant
        

        Compliant solution

        if ( b1 && b2 )
        if ( !b1 )
        if ( b1 == false )
        if ( b1 == b2 )
        if ( b1 != b2 )
        s8a = b1 ? 3 : 7;
        

        Exceptions

        Operators |= and &= are ignored when used with bool operands. Operator ++ is also ignored with a bool operand because it is covered by rule S2668.

        void test(bool b1, bool b2, int i1) {
          b1 |= b2; // ignored
          b1++; // ignored here, handled by S2668
          b1 &= b2; // ignored
          b1 &= i1; // Noncompliant; right operand is not a bool
        }
        
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