MISRA.FUNC.SPEC.OVRLD

Viable function set for a function call contains an overloaded template and its explicit specialization.

MISRA-C++ Rule 14-8-1 (required): Overloaded function templates shall not be explicitly specialized.

Rationale

Explicit specializations will be considered only after overload resolution has chosen a best match from the set of primary function templates. This may be inconsistent with developer expectations.

Example

template <typename T> void f ( T );   // overload Example 1
template <typename T> void f ( T* );  // overload Example 2

template <> void f<int32_t*> ( int32_t* ); // explicit specialization of
                                           // Example 1
void b ( int32_t * i )
{
   f ( i );              // Non-compliant
                         // - Calls Example 2, f<int32_t*>
}

Where a template is not overloaded with other templates, or is overloaded with non-template functions then it can be explicitly specialized, as it is consistent with developer expectation that the explicit specializations will only be considered if that primary template is chosen.

template <typename T> void f ( T );          // Example 1
template <> void f<int32_t*> ( int32_t* );   // Example 2

void b ( int32_t * i )
{
   f ( i );                // Compliant
                           // - Calls Example 2, f<int32_t*>
}