Does variable declaration mean memory allocation?

Question

Will it be precise to say that in

void f() {
    int x;
    ...
}

\"int x;\" means allocating sizeof(int) bytes o

Answer 1

I think it depends on compiler. I used the default compiler for Code::Blocks and Dev-C++ and it looks like memory is allocated during initialization. In following cout statement, changing n2 to n1 will give the same answer. But if I initialize n1 to some value, or if I display n2 before I display the average, I will get a different answer which it is garbage. Note that VS does correctly handles this by giving error since variables are not initialized.

void getNums();
void getAverage();

int main()
{
    getNums();
    getAverage();

    return 0;
}
void getNums()
{
    int num1 = 4;
    double total = 10;
}
void getAverage()
{
    int counter;
    double n1 , n2;
    cout << n2/counter << endl;
}