test.cpp

#include <iostream>

const float GAIN(1.5);

void
multiply(float *f)
{
   (*f) *= GAIN;   
}

void
multiply_long(float *f)
{
   (*f) = (*f) * GAIN;
}

void
multiply_with_temp(float *f)
{
   float t = *f;
   t = t * GAIN;
   *f = t;
}

int main()
{
   float *const f = new float(1);
}