Benefits of using “const” with scalar type? (e.g. “const double” or “const int”)

Question

///////////////////////////////////////
class A {
    ...
    const double funA(void)
    {...}
};

A a;
double x = a.funA(); 
// although the intention is to
// enf         


        

Answer 1

In practice, there is no real benefits for scalars.

However, in theory it could help a compiler to perform additional optimizations, such as passing a reference to the constant instead of copying the double value.