One solution would be to factor all of the mutation code into a lambda expression. Do all of the mutation in the lambda expression and assign the result out to a const int
in the method scope. For example
void SomeFunction(const int p1) {
auto calcA = [&]() {
int a = p1;
a *= 50;
a %= 10;
if(example())
a = 0;
..
return a;
};
const int a = calcA();
...
}
or even
void SomeFunction(const int p1) {
const int a = [&]() {
int a = p1;
a *= 50;
a %= 10;
if(example())
a = 0;
..
return a;
}();
...
}