[c++] C++ initial value of reference to non-const must be an lvalue

I'm trying to send value into function using reference pointer but it gave me a completely non-obvious error to me

#include "stdafx.h"
#include <iostream>

using namespace std;

void test(float *&x){

    *x = 1000;
}

int main(){
    float nKByte = 100.0;
    test(&nKByte);
    cout << nKByte << " megabytes" << endl;
    cin.get();
}

Error : initial value of reference to non-const must be an lvalue

I have no idea what I must do to repair above code, can someone give me some ideas on how to fix that code? thanks :)

The &nKByte creates a temporary value, which cannot be bound to a reference to non-const.

You could change void test(float *&x) to void test(float * const &x) or you could just drop the pointer altogether and use void test(float &x); /*...*/ test(nKByte);.

When you call test with &nKByte, the address-of operator creates a temporary value, and you can't normally have references to temporary values because they are, well, temporary.

Either do not use a reference for the argument, or better yet don't use a pointer.