MISRA.FUNC.VIRTUAL.UNUSEDPAR

Formal parameter of a virtual function set is not used.

MISRA-C++ Rule 0-1-12 (required): There shall be no unused parameters (named or unnamed) in the set of parameters for a virtual function and all the functions that override it.

Rationale

Unused function parameters are often due to design changes and can lead to mismatched parameter lists.

Example

class A
    {
    public:
        virtual void withunusedpara     ( uint16_t * para1,
                                          int16_t unusedpara ) = 0;
        virtual void withoutunusedpara  ( uint16_t * para1,
                                          int16_t & para2 ) = 0;
    };
    class B1: public A
    {
    public:
        virtual void withunusedpara    ( uint16_t * para1,
                                         int16_t unusedpara )
    {
        *para1 = 1U;
    }
        virtual void withoutunusedpara ( uint16_t * para1,
                                         int16_t & para2 )
    {
        *para1 = 1U;
    }
};
    class B2: public A
    {
    public:
        virtual void withunusedpara    ( uint16_t * para1,
                                         int16_t unusedpara )
    {
        *para1 = 1U;
    }
        virtual void withoutunusedpara ( uint16_t * para1,
                                         int16_t & para2 )
    {
        para2 = 0;
    }
};