Passing arguments via an ellipsis bypasses the type checking performed by the compiler. Additionally, passing an argument with non-POD class type
leads to undefined behavior. Note that the rule specifies "defined" (and not "declared") so as to permit the use of existing library functions.
Noncompliant code example
void MyPrintf ( char_t * pFormat, ... ) // Noncompliant
{
// ...
}